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| Domain | Tasks | Points | Clinical Significance |
|---|---|---|---|
| Orientation | Time (5), Place (5) | 10 | Impaired early in dementia |
| Registration | Repeat 3 words | 3 | Tests immediate memory |
| Attention | Serial 7s or spell WORLD backwards | 5 | Impaired in delirium |
| Recall | Recall 3 words after 5 min | 3 | Tests short-term memory |
| Language | Name objects, repeat phrase, follow commands | 8 | Aphasia screening |
| Construction | Copy intersecting pentagons | 1 | Visuospatial function |
Scoring:
24-30: Normal
18-23: Mild cognitive impairment
0-17: Severe cognitive impairment
| CN | Name | Type | Function | Test |
|---|---|---|---|---|
| I | Olfactory | Sensory | Smell | Coffee, cloves (each nostril) |
| II | Optic | Sensory | Vision | Visual acuity, fields, fundoscopy |
| III | Oculomotor | Motor | Eye movement (SR, IR, MR, IO), pupil, eyelid | H-pattern, pupil reaction, ptosis |
| IV | Trochlear | Motor | Eye movement (SO - depresses adducted eye) | Look down and in |
| V | Trigeminal | Both | Facial sensation, chewing | Cotton wool (3 divisions), jaw jerk, clench teeth |
| VI | Abducens | Motor | Eye movement (LR - abducts eye) | Look laterally |
| VII | Facial | Both | Facial expression, taste (ant 2/3), lacrimation | Smile, close eyes tight, raise eyebrows |
| VIII | Vestibulocochlear | Sensory | Hearing, balance | Whisper test, Rinne, Weber |
| IX | Glossopharyngeal | Both | Taste (post 1/3), gag reflex, swallow | Gag reflex, say "Ah" |
| X | Vagus | Both | Swallow, phonation, visceral | Uvula deviation, hoarseness |
| XI | Spinal accessory | Motor | SCM and trapezius | Shrug shoulders, turn head against resistance |
| XII | Hypoglossal | Motor | Tongue movement | Stick out tongue, move side to side |
| CN | Name | Type | Function | Test |
|---|---|---|---|---|
| I | Olfactory | Sensory | Smell | Coffee, cloves (each nostril) |
| II | Optic | Sensory | Vision | Visual acuity, fields, fundoscopy |
| III | Oculomotor | Motor | Eye movement (SR, IR, MR, IO), pupil, eyelid | H-pattern, pupil reaction, ptosis |
| IV | Trochlear | Motor | Eye movement (SO - depresses adducted eye) | Look down and in |
| V | Trigeminal | Both | Facial sensation, chewing | Cotton wool (3 divisions), jaw jerk, clench teeth |
| VI | Abducens | Motor | Eye movement (LR - abducts eye) | Look laterally |
| VII | Facial | Both | Facial expression, taste (ant 2/3), lacrimation | Smile, close eyes tight, raise eyebrows |
| VIII | Vestibulocochlear | Sensory | Hearing, balance | Whisper test, Rinne, Weber |
| IX | Glossopharyngeal | Both | Taste (post 1/3), gag reflex, swallow | Gag reflex, say "Ah" |
| X | Vagus | Both | Swallow, phonation, visceral | Uvula deviation, hoarseness |
| XI | Spinal accessory | Motor | SCM and trapezius | Shrug shoulders, turn head against resistance |
| XII | Hypoglossal | Motor | Tongue movement | Stick out tongue, move side to side |
Mnemonic for names: "Oh Oh Oh To Touch And Feel Very Good Velvet AH!"
Mnemonic for Sensory/Motor/Both: "Some Say Marry Money But My Brother Says Big Brains Matter More"
S = Sensory (I, II, VIII)
M = Motor (III, IV, VI, XI, XII)
B = Both (V, VII, IX, X)
| Feature | UMN Lesion | LMN Lesion (Bell's Palsy) |
|---|---|---|
| Forehead | SPARED(bilateral innervation) | INVOLVED(cannot wrinkle forehead) |
| Eye closure | Possible | Impossible |
| Cause | Stroke (contralateral cortex) | Bell's palsy, Ramsay Hunt, tumor |
| Associated | Other UMN signs | Hyperacusis, loss of taste ant 2/3 tongue |
Acute onset unilateral LMN facial weakness
Inability to close eye, wrinkle forehead, smile
Hyperacusis (stapedius muscle)
Loss of taste anterior 2/3 tongue
Postauricular pain may precede weakness
Management:
Prednisolone 1 mg/kg × 7-10 days (start within 72 hours)
Eye protection (artificial tears, tape eye at night)
Acyclovir if Ramsay Hunt suspected
Prognosis: 70% complete recovery in 3-6 months
BULBAR vs PSEUDOBULBAR PALSY:
| Feature | Bulbar Palsy | Pseudobulbar Palsy |
|---|---|---|
| Lesion | LMN (CN IX, X, XII nuclei/nerves) | UMN (bilateral corticobulbar tracts) |
| Tongue | Wasted, fasciculations | Spastic, NO wasting |
| Jaw jerk | Normal/absent | Brisk |
| Gag reflex | Absent | Normal/brisk |
| Speech | Flaccid dysarthria | Spastic dysarthria |
| Emotion | Normal | Emotional lability(pseudobulbar affect) |
| Causes | MND, GBS, myasthenia | Stroke, MS, MND (late) |
| Feature | UMN Lesion | LMN Lesion |
|---|---|---|
| Tone | ↑Spasticity (clasp-knife) | ↓Flaccidity |
| Power | ↓(weakness) | ↓↓(more severe weakness) |
| Reflexes | ↑↑Hyperreflexia | ↓↓Hyporeflexia/absent |
| Plantars | Extensor (Babinski +ve) | Flexor (normal) |
| Wasting | Mild (disuse atrophy) | Marked wasting |
| Fasciculations | Absent | Present |
| Clonus | Present | Absent |
| Distribution | Pyramidal (extensors arm, flexors leg weak) | Specific muscles/myotomes |
| Examples | Stroke, MS, spinal cord compression | Polio, GBS, nerve injury, MND |
| Grade | Description | Clinical |
|---|---|---|
| 0 | No movement | Complete paralysis |
| 1 | Flicker of contraction | Visible/palpable but no movement |
| 2 | Movement with gravity eliminated | Can move if supported |
| 3 | Movement against gravity | Can lift but not against resistance |
| 4 | Movement against resistance | Weak against resistance |
| 5 | Normal power | Full strength |
Finer grading: 4-, 4, 4+ (for subtle weakness)
| Modality | Pathway | Decussation | Clinical Test |
|---|---|---|---|
| Pain, Temperature | Spinothalamic (lateral) | Immediately at spinal level(2-3 segments up) | Pinprick, hot/cold |
| Vibration, Proprioception | Dorsal column-medial lemniscus | At medulla(decussates in brainstem) | Tuning fork 128 Hz, joint position |
| Light Touch | Both pathways | Variable | Cotton wool |
Clinical Significance:
Hemisection of cord (Brown-Séquard):
Ipsilateral: Loss of vibration, proprioception, UMN signs
Contralateral: Loss of pain, temperature (2 levels below)
| Pattern | Distribution | Causes |
|---|---|---|
| Glove-and-stocking | Distal, symmetric | Peripheral neuropathy (DM, alcohol, B12 deficiency) |
| Dermatomal | Single dermatome | Nerve root (radiculopathy), herpes zoster |
| Hemibody | One side of body | Cortical/thalamic stroke, spinal hemisection |
| Suspended/Cape-like | Arms/chest, spares legs | Syringomyelia (central cord) |
| Saddle anesthesia | Perineum, buttocks, inner thighs | Cauda equina syndrome |
| Dissociated | Loss of pain/temp, preserved touch/vibration | Syringomyelia, anterior spinal artery occlusion |
| Pattern | Distribution | Causes |
|---|---|---|
| Glove-and-stocking | Distal, symmetric | Peripheral neuropathy (DM, alcohol, B12 deficiency) |
| Dermatomal | Single dermatome | Nerve root (radiculopathy), herpes zoster |
| Hemibody | One side of body | Cortical/thalamic stroke, spinal hemisection |
| Suspended/Cape-like | Arms/chest, spares legs | Syringomyelia (central cord) |
| Saddle anesthesia | Perineum, buttocks, inner thighs | Cauda equina syndrome |
| Dissociated | Loss of pain/temp, preserved touch/vibration | Syringomyelia, anterior spinal artery occlusion |
| Reflex | Root | How to Elicit | Normal Response |
|---|---|---|---|
| Biceps | C5, C6 | Tap biceps tendon | Elbow flexion |
| Triceps | C7, C8 | Tap triceps tendon above elbow | Elbow extension |
| Supinator | C5, C6 | Tap brachioradialis tendon | Forearm flexion, supination |
| Knee (patellar) | L3, L4 | Tap patellar tendon | Knee extension |
| Ankle (Achilles) | S1, S2 | Tap Achilles tendon | Plantar flexion |
Grading:
0: Absent
1+: Diminished
2+: Normal
3+: Brisk
4+: Very brisk with clonus
Reinforcement (if reflex difficult to elicit):
Upper limb: Patient clenches teeth or pulls hands apart (Jendrassik maneuver)
Lower limb: Patient hooks fingers together and pulls
| Reflex | How to Elicit | Positive Response | Significance |
|---|---|---|---|
| Babinski | Stroke lateral sole of foot heel to toe | Big toeextends(dorsiflexes), other toes fan out | UMN lesion |
| Hoffman | Flick terminal phalanx of middle finger | Thumb and index finger flex | UMN lesion (cervical cord) |
| Jaw jerk | Tap chin with mouth slightly open | Excessive jaw closure | Pseudobulbar palsy |
| Glabellar tap | Tap forehead repeatedly | Persistent blinking (doesn't habituate) | Parkinsonism |
Mnemonic: DANISH
Dysdiadochokinesia (inability to perform rapid alternating movements)
Ataxia (wide-based gait, past-pointing)
Nystagmus (horizontal, worse looking to side of lesion)
Intention tremor (finger-nose test)
Slurred speech (scanning/staccato speech)
Hypotonia
Tests:
Finger-nose test: Intention tremor, past-pointing, dysmetria
Heel-shin test: Ataxia in lower limbs
Rapid alternating movements: Dysdiadochokinesia
Romberg test: Negative in cerebellar (ataxia present with eyes open and closed)
Gait: Wide-based, staggering, veering to side of lesion
Rebound phenomenon: Ask patient to flex arm against resistance, then release - overshoots
Lateralizing signs: Cerebellar signs are IPSILATERAL to the lesion
| Gait Type | Description | Causes |
|---|---|---|
| Hemiplegic | Arm flexed, leg extended, circumduction | Stroke |
| Spastic (scissors) | Legs stiff, cross with each step | Cerebral palsy, bilateral stroke |
| Parkinsonian | Stooped, shuffling, reduced arm swing, festination | Parkinson disease |
| Ataxic | Wide-based, staggering, unsteady | Cerebellar disease, alcohol |
| Sensory ataxic | Wide-based, stamps feet, worse with eyes closed | Dorsal column loss (B12 deficiency, tabes dorsalis) |
| Steppage (foot drop) | High-stepping, foot slaps ground | Common peroneal nerve palsy, L5 radiculopathy |
| Waddling | Side-to-side sway, Trendelenburg | Proximal myopathy (muscular dystrophy) |
| Antalgic | Limping to avoid pain | Arthritis, fracture |
| Type | Mechanism | Percentage | Features |
|---|---|---|---|
| Ischemic | Thrombosis, embolism | 85% | Sudden focal deficit, may have TIA |
| Hemorrhagic | Intracerebral bleed | 10% | Severe headache, vomiting,↓consciousness |
| Subarachnoid | Aneurysm rupture | 5% | "Thunderclap headache", neck stiffness |
| Factor | Points |
|---|---|
| Age≥60 years | 1 |
| BP≥140/90 | 1 |
| Clinical features: Unilateral weakness | 2 |
| Clinical features: Speech impairment without weakness | 1 |
| Duration:≥60 min | 2 |
| Duration: 10-59 min | 1 |
| Diabetes | 1 |
Score interpretation:
0-3: Low risk (1% stroke at 2 days)
4-5: Moderate risk (4%)
6-7: High risk (8%)
Management:
High risk (≥4): Admit, investigate, start treatment
Low risk: Can manage outpatient with urgent workup
Start dual antiplatelet (aspirin + clopidogrel) × 21 days
Investigate for cause
Secondary prevention as per ischemic stroke
| Complication | Timing | Management |
|---|---|---|
| Rebleeding | First 24 hours (peak) | Early aneurysm securement |
| Vasospasm/DCI | Days 4-14(peak day 7) | Nimodipine, maintain euvolemia, induced hypertension |
| Hydrocephalus | Acute or chronic | EVD, VP shunt |
| Hyponatremia | Days 3-10 | SIADH vs cerebral salt wasting - treat accordingly |
| Seizures | Any time | Antiepileptics |
| Type | Features | EEG | Age Group |
|---|---|---|---|
| Tonic-clonic | Loss of consciousness, tonic stiffening→clonic jerking, post-ictal confusion | Generalized spike-wave | Any age |
| Tonic | Sudden bilateral muscle stiffening, falls | Generalized spike-wave | Children (Lennox-Gastaut) |
| Clonic | Rhythmic jerking of limbs | Generalized spike-wave | Infants |
| Absence | Sudden brief loss of consciousness, staring, no post-ictal confusion | 3 Hz spike-and-wave | Children (6-10 years) |
| Myoclonic | Sudden brief involuntary muscle jerks | Polyspike-wave | Adolescents (JME) |
| Atonic (drop attacks) | Sudden loss of muscle tone, falls | Generalized spike-wave | Children (Lennox-Gastaut) |
| Feature | Absence Seizure | Generalized Tonic-Clonic |
|---|---|---|
| Duration | 5-30 seconds | 1-3 minutes |
| Onset | Abrupt | May have aura |
| Consciousness | Brief loss | Complete loss |
| Motor activity | Minimal (lid flutter) | Tonic then clonic |
| Post-ictal confusion | NONE | Present (minutes-hours) |
| Triggered by | Hyperventilation, photic stimulation | Variable |
| EEG | 3 Hz spike-and-wave | Generalized spike-wave |
| Age | Children 6-10 years | Any age |
| Treatment | Ethosuximide, valproate | Valproate, levetiracetam |
| Syndrome | Age of Onset | Seizure Type | EEG | Treatment | Prognosis |
|---|---|---|---|---|---|
| Benign childhood epilepsy with centrotemporal spikes | 3-13 years | Focal motor (face/hand) | Centrotemporal spikes | Often self-resolving | Excellent |
| Childhood absence epilepsy | 6-10 years | Absence seizures | 3 Hz spike-wave | Ethosuximide | Excellent (most outgrow) |
| Juvenile myoclonic epilepsy (JME) | 12-18 years | Myoclonic + GTC | Polyspike-wave | Valproate | Good (lifelong treatment needed) |
| Temporal lobe epilepsy | Variable | Focal impaired awareness, automatisms | Temporal lobe abnormality | Carbamazepine, surgery if refractory | Variable |
| Lennox-Gastaut syndrome | 1-7 years | Multiple types (atonic, tonic, absence) | Slow spike-wave (<2.5 Hz) | Multiple drugs, VNS | Poor |
| Seizure Type | First-line | Alternatives | Notes |
|---|---|---|---|
| Generalized tonic-clonic | Valproate | Levetiracetam, lamotrigine | Valproate most effective for generalized |
| Focal seizures | Carbamazepine | Levetiracetam, lamotrigine | Gold standard for temporal lobe epilepsy |
| Absence seizures | Ethosuximide | Valproate | Ethosuximide = first choice for pure absence |
| Myoclonic seizures | Valproate | Levetiracetam | Avoid carbamazepine (worsens myoclonia) |
| Multiple seizure types | Valproate | Levetiracetam | Most broadly effective |
Key Drug Facts:
| Drug | Mechanism | Important Side Effects | Special Considerations |
|---|---|---|---|
| Valproate | ↑GABA | Hepatotoxicity, thrombocytopenia, weight gain, hair loss, neural tube defects | Teratogenic- avoid in women of childbearing age |
| Carbamazepine | Na+ channel blocker | Rash (Stevens-Johnson), agranulocytosis, hyponatremia, diplopia | Check HLA-B*1502 in Asian patients (SJS risk) |
| Phenytoin | Na+ channel blocker | Gingival hyperplasia, hirsutism, megaloblastic anemia, teratogenic | Narrow therapeutic index, non-linear kinetics |
| Lamotrigine | Na+ channel blocker | Rash (SJS risk - start low, go slow) | Safe in pregnancy, requires dose adjustment with valproate |
| Levetiracetam | SV2A modulator | Irritability, depression, headache | Few drug interactions, no need for blood level monitoring |
| Ethosuximide | Ca2+ channel blocker | GI upset, headache | Only for absence seizures |
| Phenobarbital | GABA-A enhancer | Sedation, dependence, cognitive impairment | Most available and affordable in Pakistan |
| Stage | CT/MRI Finding | Description |
|---|---|---|
| Vesicular | Thin-walled cyst with scolex | Well-defined, cyst-like lesion |
| Colloidal/vesicular-granular | Ring-enhancing cyst with surrounding edema | Most common presentation on imaging |
| Granular-calcific | Calcified nodule | Small, bright on CT |
| Calcific/nodular | Dense calcification | End-stage, dead parasite |
Pathognomonic sign: "Dot-swirl sign" on MRI (scolex within cystic lesion)
| Condition | Key Differentiating Feature |
|---|---|
| Essential tremor | Action tremor (not resting), no bradykinesia, familial |
| Wilson disease | Young patient, Kayser-Fleischer rings, copper studies |
| PSP (Progressive supranuclear palsy) | Early falls (backward), vertical gaze palsy, "surprised expression" |
| MSA (Multiple system atrophy) | Cerebellar ataxia, autonomic dysfunction, poor response to levodopa |
| Drug-induced parkinsonism | History of antipsychotics/antiemetics |
| Feature | Essential Tremor | Parkinsonian Tremor |
|---|---|---|
| Type | Action/intentiontremor | Restingtremor |
| Frequency | 6-12 Hz | 4-6 Hz |
| Location | Hands (bilateral), head, voice | Hands (often unilateral at onset) |
| Worse with | Writing, holding cup | Rest |
| Better with | Rest | Movement |
| Bradykinesia | Absent | Present |
| Rigidity | Absent | Present |
| Family history | Often positive (autosomal dominant) | Usually negative |
| Age | Bimodal (young adults, elderly) | >50 years |
| Type | Features | Examples |
|---|---|---|
| Generalized | Whole body, childhood onset | Idiopathic torsion dystonia |
| Focal | Specific muscle group | Torticollis (neck), blepharospasm (eyelid), writer's cramp |
| Segmental | Adjacent body regions | Cervical + upper limb |
Management:
Botulinum toxin injection - First-line for focal dystonia
Anticholinergics (benztropine)
DBS for severe generalized dystonia
| Feature | Without Aura (80%) | With Aura (20%) |
|---|---|---|
| Aura | Absent | Present (30-60 min before headache) |
| Aura types | - | Visual (most common), sensory, motor, speech |
| Visual aura | - | Scintillating scotoma, fortification spectra, visual snow |
| Headache onset | Spontaneous | Usually after aura |
| Risk of stroke | Lower | Higher (especially in women on OCPs who smoke) |
| Category | Common Triggers |
|---|---|
| Dietary | Chocolate, aged cheese, red wine, caffeine (withdrawal), skipped meals |
| Hormonal | Menstruation, OCP changes |
| Environmental | Bright lights, loud sounds, strong smells, temperature changes |
| Stress | Emotional stress, sleep changes |
| Other | Dehydration, physical exertion |
| Severity | Treatment | Notes |
|---|---|---|
| Mild | NSAIDs (ibuprofen 400-600 mg) | Take early in attack |
| Moderate | NSAIDs + antiemetic (metoclopramide) | Treat nausea to improve drug absorption |
| Severe | Triptans(sumatriptan 50-100 mg oral, or 6 mg SC) | 5-HT1B/1D agonists, most effective acute treatment |
| Very severe | IV NSAIDs or IV ketorolac + antiemetic in hospital | If oral treatment fails |
Contraindications to Triptans:
Ischemic heart disease, uncontrolled HTN
Basilar/hemiplegic migraine
Age <18, pregnancy
Within 24 hours of ergotamine
| Drug Class | Examples | Notes |
|---|---|---|
| Beta-blockers | Propranolol(most evidence) | First-line |
| Anticonvulsants | Topiramate, valproate | Valproate teratogenic |
| Antidepressants | Amitriptyline | Also helps tension headache |
| Others | Magnesium, riboflavin, CGRP antibodies (erenumab) | CGRP antibodies: very effective but expensive |
| Sign | Mechanism |
|---|---|
| Papilledema | Axoplasmic flow blocked in optic nerve |
| Vomiting | Stimulation of vomiting center in medulla |
| "Sunset sign" | Downward gaze palsy (in children with hydrocephalus) |
| 6th nerve palsy | Most vulnerable cranial nerve (long intracranial course) - FALSE LOCALIZING SIGN |
| Declining GCS | Reticular activating system compression |
| Age Group | Most Common Organisms | Treatment |
|---|---|---|
| Neonates (0-3 months) | GBS, E. coli, Listeria | Ampicillin + Gentamicin (or Cefotaxime) |
| Infants/Children (3 months - 18 years) | Neisseria meningitidis, Strep pneumoniae | Ceftriaxone + Vancomycin |
| Adults (18-50 years) | Strep pneumoniae, Neisseria meningitidis | Ceftriaxone + Vancomycin |
| Elderly (>50 years) | Strep pneumoniae, Listeria, Gram negatives | Ceftriaxone + Vancomycin + Ampicillin (for Listeria) |
| Immunocompromised | Listeria, Gram negatives, Crypto | Ampicillin + Ceftriaxone + Vancomycin |
| Parameter | Finding |
|---|---|
| Appearance | Clear or slightly turbid,"cobweb clot"(fibrin clot on standing) |
| Cells | 50-500 (lymphocytic predominance) |
| Protein | ↑↑↑(100-500 mg/dL) - very high |
| Glucose | ↓↓(<40% of serum) - very low |
| ADA (Adenosine deaminase) | >10 U/L(sensitivity 80%, specificity 90%) |
| AFB smear | Positive in only 10-20% (low sensitivity) |
| Culture | Gold standard but takes 4-8 weeks |
| GeneXpert MTB/RIF | Rapid, detects TB DNA (most useful test) |
| Feature | Meningitis | Encephalitis |
|---|---|---|
| Consciousness | Usually preserved | Altered (confusion,↓GCS) |
| Seizures | Rare | Common |
| Focal signs | Rare | Common |
| Behavioral changes | Rare | Common |
| Hallucinations | Rare | Common |
Lymphocytic pleocytosis (10-500)
↑ RBCs (hemorrhagic necrosis)
↑ Protein
Normal glucose
PCR for HSV DNA - Most sensitive and specific test (gold standard)
MRI (Most important imaging):
Bilateral temporal lobe hyperintensities on T2/FLAIR
Hemorrhagic necrosis
May be unilateral early
Periodic lateralized epileptiform discharges (PLEDs) in temporal regions
Slow wave activity
| Feature | Meningitis | Encephalitis |
|---|---|---|
| Site | Meninges | Brain parenchyma |
| Consciousness | Usually alert | Altered |
| Seizures | Rare | Common |
| Focal signs | Rare | Common |
| Headache | Severe | Variable |
| Neck stiffness | Present | May be absent |
| Behavioral changes | Rare | Common |
| MRI | Normal or meningeal enhancement | Parenchymal abnormalities |
| CSF | ↑WBC,↓glucose (bacterial) | ↑WBC, may have RBCs, PCR positive |
| Symptom | Description | Frequency |
|---|---|---|
| Optic neuritis | Painful vision loss in one eye, central scotoma,↓color vision (red desaturation), RAPD | Most common presenting feature (25%) |
| Sensory symptoms | Numbness, tingling, paresthesias (often in limbs) | 40% |
| Motor weakness | Limb weakness, spasticity, UMN signs | 30-40% |
| Diplopia | Internuclear ophthalmoplegia (INO), CN VI palsy | 15% |
| Ataxia | Cerebellar signs, intention tremor, dysmetria | 20% |
| Bladder dysfunction | Urgency, frequency, incontinence | Common |
| Lhermitte sign | Electric shock sensation down spine with neck flexion | Classic sign |
| Uhthoff phenomenon | Symptoms worsen with heat/exercise (hot bath, fever) | Classic sign |
| Fatigue | Overwhelming fatigue | Very common |
| Type | Description | Frequency | Features |
|---|---|---|---|
| Relapsing-Remitting (RRMS) | Discrete attacks with complete/partial recovery | 85% at onset | Most common initial presentation |
| Secondary Progressive (SPMS) | Initial RRMS→progressive worsening | 50% of RRMS convert in 10 years | Gradual decline after relapses stop |
| Primary Progressive (PPMS) | Progressive from onset, no relapses | 10-15% | Older age at onset, worse prognosis |
| Progressive-Relapsing | Progressive from onset WITH relapses | <5% | Rare |
Relapse/Exacerbation defined as:
New symptom or worsening of old symptom
Lasting >24 hours
NOT due to fever/infection (pseudorelapse)
Separated by ≥30 days from previous relapse
| Drug | Mechanism | Route | Side Effects |
|---|---|---|---|
| Interferon-β(IFN-β) | Immunomodulator | SC/IM injection | Flu-like symptoms, depression, hepatotoxicity |
| Glatiramer acetate | Immunomodulator | SC injection | Injection site reactions |
| Teriflunomide | Inhibits pyrimidine synthesis | Oral | Diarrhea, hepatotoxicity, teratogenic |
| Dimethyl fumarate | Unknown | Oral | Flushing, GI upset |
Second-line (Severe/Refractory RRMS):
| Drug | Mechanism | Side Effects |
|---|---|---|
| Fingolimod | S1P receptor modulator | Bradycardia (first dose), macular edema, infections |
| Natalizumab | Anti-α4 integrin antibody | PML (Progressive Multifocal Leukoencephalopathy)risk with JC virus |
| Alemtuzumab | Anti-CD52 monoclonal antibody | Autoimmune thyroid disease, ITP |
| Ocrelizumab | Anti-CD20 antibody | Infusion reactions, infections |
| Rituximab | Anti-CD20 antibody | Similar to ocrelizumab |
| Symptom | Treatment |
|---|---|
| Spasticity | Baclofen, tizanidine, gabapentin |
| Fatigue | Amantadine, modafinil |
| Neuropathic pain | Gabapentin, pregabalin, amitriptyline |
| Bladder dysfunction | Anticholinergics (oxybutynin), intermittent catheterization |
| Depression | SSRIs |
| Tremor | Propranolol, primidone (often refractory) |
Non-pharmacological:
Physiotherapy (maintain mobility, prevent contractures)
Occupational therapy
Speech therapy
Cognitive rehabilitation
Avoid heat exposure (Uhthoff phenomenon)
Regular exercise (swimming in cool water ideal)
Vitamin D supplementation
| Subtype | Frequency | Features |
|---|---|---|
| AIDP (Acute Inflammatory Demyelinating Polyneuropathy) | 90% in West, 60% in Pakistan/Asia | Classic ascending weakness, areflexia, demyelination |
| AMAN (Acute Motor Axonal Neuropathy) | 30-40% in Pakistan/Asia | Pure motor, worse prognosis, associated with C. jejuni |
| AMSAN (Acute Motor-Sensory Axonal Neuropathy) | Rare | Motor + sensory, axonal, worse prognosis |
| Miller Fisher Syndrome | 5% | Triad: Ataxia, Areflexia, Ophthalmoplegia(Anti-GQ1b antibodies) |
| Pharyngeal-Cervical-Brachial | Rare | Weakness of oropharynx, neck, shoulder |
| Complication | Frequency | Management |
|---|---|---|
| Respiratory failure | 30% | Intubation, mechanical ventilation |
| Cardiac arrhythmias | Common | Continuous monitoring |
| Autonomic instability | Common | Avoid sudden interventions |
| Pneumonia | Common in ventilated | Antibiotics |
| DVT/PE | Common | Prophylactic anticoagulation |
| Pressure ulcers | Common | Frequent repositioning |
| Contractures | Common | Physiotherapy |
| Pain | 90% | Multimodal analgesia |
| Feature | Multiple Sclerosis | Guillain-BarréSyndrome |
|---|---|---|
| Location | CNS(brain, spinal cord) | PNS(peripheral nerves) |
| Onset | Relapsing-remitting (usually) | Acute, monophasic |
| Progression | Chronic (years) | Acute (days to weeks) |
| Reflexes | ↑Hyperreflexia(UMN) | ↓↓Areflexia(LMN) |
| Plantars | Extensor (Babinski +ve) | Flexor (normal) |
| CSF | Oligoclonal bands,↑IgG index | Albuminocytologic dissociation |
| Treatment | Steroids, immunomodulators | IVIg, plasmapheresis (NOT steroids) |
| Prognosis | Chronic, progressive | Most recover fully |
| Type | Age | Features | Antibodies |
|---|---|---|---|
| Ocular MG | Any | Weakness limited to eyelids/extraocular muscles | Anti-AChR (50%) |
| Generalized MG | Bimodal (20-40, 60-80) | Ocular + bulbar/limb/respiratory | Anti-AChR (80-90%) |
| MuSK-positive MG | Young women | Prominent bulbar/facial/respiratory, no ocular | Anti-MuSK (5-10%) |
| Seronegative MG | Any | Both antibodies negative | Neither (5-10%) |
| Antibody | Frequency | Notes |
|---|---|---|
| Anti-AChR | 85% generalized, 50% ocular | Most specific test |
| Anti-MuSK | 5-10% (in AChR-negative patients) | Severe disease, prominent bulbar involvement |
| Anti-LRP4 | Rare | In "double seronegative" patients |
Electrophysiology:
Repetitive Nerve Stimulation (RNS):
Stimulate nerve at 2-3 Hz
Positive: >10% decrement in amplitude from 1st to 5th stimulus
Sensitivity: 50-60% (low)
More sensitive in generalized MG
Single Fiber EMG (SF-EMG):
Gold standard electrophysiological test
Shows increased jitter (variability in neuromuscular transmission)
Sensitivity: >95%
Not specific (can be abnormal in other conditions)
Imaging:
CT/MRI Chest:
Look for thymoma (15% of MG patients)
Thymic hyperplasia (60-70% of young patients)
ALL MG patients need chest imaging
| Drug | Dose | Onset | Side Effects |
|---|---|---|---|
| Azathioprine | 2-3 mg/kg/day | 3-6 months (slow) | Hepatotoxicity, bone marrow suppression, GI upset |
| Mycophenolate mofetil | 1-1.5 g BD | 3-6 months | GI upset, infections |
| Cyclosporine | 3-5 mg/kg/day | 1-2 months | Nephrotoxicity, hypertension, hirsutism |
| Tacrolimus | 3-5 mg/day | 2-3 months | Nephrotoxicity, DM, tremor |
Pakistan Context:
Pyridostigmine + Prednisolone most commonly used
Azathioprine most common steroid-sparing agent (affordable)
Newer agents (mycophenolate, tacrolimus) increasingly available but expensive
Rapid Immunotherapy (For severe disease/crisis):
Plasmapheresis:
5-6 exchanges over 2 weeks
Onset: Within days (rapid)
Duration: 4-8 weeks
Used for: Myasthenic crisis, pre-surgery, refractory disease
IV Immunoglobulin (IVIg):
Dose: 2 g/kg over 2-5 days (0.4 g/kg/day × 5 days)
Onset: Within days
Duration: 4-12 weeks
Equally effective as plasmapheresis
Easier to administer (no special equipment needed)
Thymectomy:
Indications:
Thymoma (absolute indication - risk of malignancy)
Generalized MG in patients <60 years (especially anti-AChR positive)
Benefit greater in young patients with thymic hyperplasia
Not useful in: Ocular MG, MuSK-positive MG
Benefit:
May take 1-2 years to see full effect
Remission in 30-40%
Improvement in 50-60%
| Feature | Myasthenic Crisis | Cholinergic Crisis |
|---|---|---|
| Cause | Under-treatment, disease worsening | Excessive anticholinesterase(pyridostigmine overdose) |
| Weakness | Severe | Severe |
| Pupils | Normal | Miosis (constricted) |
| Secretions | Normal/dry | ↑↑(salivation, sweating, lacrimation) |
| Fasciculations | Absent | Present |
| GI symptoms | Minimal | Abdominal cramps, diarrhea |
| Edrophonium test | Improves | Worsens |
| Treatment | IVIg/plasmapheresis | Stop pyridostigmine, atropine |
| Class | Examples | Why Avoid |
|---|---|---|
| Antibiotics | Aminoglycosides (gentamicin), fluoroquinolones (ciprofloxacin), macrolides (azithromycin) | Impair NMJ transmission |
| Cardiac | Beta-blockers (propranolol), calcium channel blockers (verapamil), quinidine | Impair NMJ transmission |
| Neuromuscular blockers | Succinylcholine, rocuronium | Prolonged paralysis |
| Magnesium | IV magnesium sulfate | Impairs ACh release |
| Others | Statins (high dose), lithium, phenytoin, chloroquine | Variable mechanisms |
| Variant | Features | Frequency |
|---|---|---|
| Classic ALS | UMN + LMN signs in limbs + bulbar | 70% |
| Progressive Muscular Atrophy (PMA) | Pure LMNsigns (no UMN) | 10% - better prognosis |
| Primary Lateral Sclerosis (PLS) | Pure UMNsigns (no LMN) | 5% - slower progression |
| Progressive Bulbar Palsy | Bulbar-onset (UMN + LMN bulbar signs) | 20% - worse prognosis |
| Flail arm/leg syndrome | Asymmetric limb-onset, slow progression | Rare - better prognosis |
| Condition | Key Differentiating Feature |
|---|---|
| Cervical spondylotic myelopathy | Sensory level, MRI shows cord compression |
| Multifocal motor neuropathy (MMN) | Pure motor,conduction blockon NCS, responds to IVIg |
| Kennedy disease | X-linked, bulbar,gynecomastia, slow progression |
| Myasthenia gravis | Fatigability, ocular involvement, improves with rest |
| Inclusion body myositis | Myopathic pattern on EMG, elevated CK |
| Thyrotoxic myopathy | Thyroid function abnormal |
| Lead poisoning | Occupational exposure, basophilic stippling |
| HTLV-1 myelopathy | Endemic areas, sensory involvement |
| Factor | Better Prognosis | Worse Prognosis |
|---|---|---|
| Age at onset | Young (<40 years) | Old (>70 years) |
| Site of onset | Limb-onset | Bulbar-onset(2-3 years) |
| Type | Pure LMN (PMA), Pure UMN (PLS) | Classic ALS |
| Respiratory | Preserved function | Early respiratory involvement |
| Genetics | Sporadic | Some familial mutations |
Survival >5 years: 20-30% Survival >10 years: 5-10% (rare)
Famous long-survivor: Stephen Hawking (lived 55 years with ALS - very exceptional)
Cause of Death:
Respiratory failure (most common - 70-80%)
Aspiration pneumonia
Sudden death (respiratory arrest)
| Feature | Myasthenia Gravis | Motor Neuron Disease |
|---|---|---|
| Age | Bimodal (young women, old men) | Middle-aged/elderly |
| Weakness pattern | Fatigable, fluctuating | Progressive, constant |
| Eye involvement | Very common (90%) | Spared(characteristic) |
| Sensory | Normal | Normal |
| Reflexes | Normal | Mixed (↑or↓)- UMN + LMN |
| Plantars | Flexor (normal) | Extensor(Babinski +ve) |
| Fasciculations | Absent | Present |
| Improvement with rest | Yes | No |
| Antibodies | Anti-AChR, anti-MuSK | None |
| EMG | Decremental response on RNS | Denervation, fasciculations |
| Treatment | Pyridostigmine, steroids, immunosuppression | Riluzole (limited), supportive |
| Prognosis | Good with treatment | Poor - fatal in 3-5 years |
Correct: B) Alzheimer disease
Concept: MMSE interpretation and amnestic pattern of Alzheimer dementia Analysis
Why B: The combination of impaired short-term memory (recall 0/3), preserved remote memory, and progressive functional decline in an older adult fits Alzheimer disease. Orientation and recall are the first MMSE domains to fall in dementia.
Discriminator: Preserved remote memory with recent-memory loss = hippocampal-predominant amnestic pattern, the Alzheimer signature.
| A) Delirium | Acute onset, fluctuating attention, and inattention on MMSE — not a progressive amnestic picture |
| C) Vascular dementia | Stepwise course with focal signs and vascular risk factors — not described here |
| D) Depression | Pseudodementia can mimic, but no mood complaint or amotivation; amnestic pattern with preserved remote memory is not characteristic |
| E) Normal pressure hydrocephalus | Would show gait apraxia, urinary incontinence, and ventriculomegaly — triad absent |
Trap: Pattern trap — 'forgets breakfast but remembers youth' is written to seduce you into age-related forgetfulness; it is the classic Alzheimer amnestic signature.
Future alert: Progressive amnesia + preserved remote memory in an elderly patient = Alzheimer until proven otherwise.
Correct: C) CT angiography of the circle of Willis
Concept: Pupil-involving CN III palsy = compressive until proven otherwise Interpretation
Why C: A dilated, poorly reactive pupil in CN III palsy indicates compression of the parasympathetic fibers on the nerve's surface — most dangerously a posterior communicating artery aneurysm. Pupil-sparing CN III palsy suggests microvascular ischemia (diabetes, hypertension).
Discriminator: Dilated pupil + CN III palsy = compressive; imaging the vessels is the urgent step; a plain CT can miss a small aneurysm.
| A) Reassure and discharge with neurology follow-up | A compressive CN III palsy cannot be safely discharged; aneurysm rupture risk is high |
| B) MRI brain without contrast | MRI is not the first-line study for aneurysm — CT angiography visualizes the vessels directly |
| D) Lumbar puncture | No meningeal signs; LP adds nothing to the diagnosis of a compressive CN III palsy |
| E) Start oral prednisolone | Steroids treat inflammatory causes; you must exclude aneurysm first |
Trap: Substitution trap — examiner swaps 'pupil-sparing' for 'pupil-involving' to test whether you know which one is the emergency.
Future alert: Pupil-involving CN III palsy = vessel imaging now; pupil-sparing = think diabetes/hypertension.
Correct: B) Right UMN facial palsy from a stroke
Concept: Forehead sparing localizes facial weakness to the UMN (contralateral cortex) Interpretation
Why B: The forehead is spared because the frontalis receives bilateral UMN innervation. Forehead involvement (inability to wrinkle) indicates an LMN lesion. Weakness of the left lower face with a contralateral motor symptom points to a right hemisphere stroke.
Discriminator: Forehead SPARED = UMN; plus ipsilateral arm weakness = contralateral cortical lesion.
| A) Left LMN facial palsy (Bell palsy) | Bell palsy would flatten the forehead on the affected side — LMN pattern — and would not cause arm weakness |
| C) Left UMN facial palsy from a stroke | A left UMN lesion would weaken the RIGHT face — crossed pattern |
| D) Left CN VII nuclear lesion | Nuclear lesion produces LMN facial weakness with forehead involvement |
| E) Myasthenia gravis | Fatigable, fluctuating weakness — not a fixed unilateral smile asymmetry |
Trap: Laterality trap — the weak face is LEFT, so the lesion is in the RIGHT cortex. Face follows the same crossed rule as limbs for UMN lesions.
Future alert: Forehead spared = UMN; forehead involved = LMN. Then cross the laterality.
Correct: B) Glove-and-stocking
Concept: Length-dependent peripheral neuropathy produces glove-and-stocking sensory loss Recall
Why B: Distal symmetric sensory loss with reduced ankle reflexes in a diabetic patient is a length-dependent polyneuropathy — the classic glove-and-stocking distribution (symptoms begin in the feet).
Discriminator: Distal onset, symmetric, areflexia, preserved power = peripheral neuropathy pattern.
| A) Dermatomal | Dermatomal loss follows a single nerve root — would be a discrete territory, not both feet |
| C) Suspended/cape-like | Cape-like loss over arms/chest with sacral sparing is central cord (syringomyelia) |
| D) Hemibody | Hemibody loss is one side of the body — cortical or spinal hemisection |
| E) Saddle anesthesia | Saddle anesthesia involves perineum and inner thighs — cauda equina syndrome |
Trap: Buzzword trap — 'pins and needles in both feet with diabetes' is the glove-and-stocking card; resist over-reading the alcohol history.
Future alert: Distal symmetric sensory loss + absent ankle jerks = length-dependent neuropathy; DM is the default cause.
Correct: B) This is a positive Romberg test and indicates dorsal column (proprioception) loss
Concept: Romberg test distinguishes proprioceptive loss from cerebellar ataxia Recall
Why B: A patient who is steady with eyes open but falls with eyes closed has a positive Romberg — dorsal column proprioceptive loss. In cerebellar disease the patient is unsteady with eyes open AND closed (Romberg negative).
Discriminator: Eyes-open steady vs eyes-closed fall = proprioceptive input is the deficit; vision compensates.
| A) This is a positive Romberg test and indicates cerebellar ataxia | Cerebellar ataxia is unsteady with eyes open too — Romberg would be negative, not positive |
| C) This is a negative Romberg test and indicates vestibular dysfunction | A fall with eyes closed IS the positive Romberg; it localizes to dorsal columns, not vestibular |
| D) A positive Romberg always indicates cerebellar disease | Exactly backwards — positive Romberg excludes cerebellar ataxia as the cause |
| E) The test is invalid because the patient chose to close his eyes | The test is standard and valid as performed |
Trap: Definition trap — many students believe 'positive Romberg = balance problem = cerebellum'. It is specifically proprioception.
Future alert: Positive Romberg = dorsal column loss; negative Romberg with ataxia = cerebellum.
Correct: A) Left middle cerebral artery (MCA)
Concept: MCA territory stroke — dominant hemisphere — causing Broca aphasia Interpretation
Why A: Hemiparesis worse in face/arm than leg, hemisensory loss, and Broca (expressive) aphasia localize to the dominant MCA territory. Gaze preference toward the lesion (left) confirms left hemisphere involvement.
Discriminator: Broca aphasia = dominant hemisphere; face/arm > leg = MCA, not ACA.
| B) Right middle cerebral artery (MCA) | Right MCA would cause left-sided weakness, neglect, and anosognosia — not aphasia |
| C) Left anterior cerebral artery (ACA) | ACA affects contralateral leg > arm with urinary incontinence — leg is spared here |
| D) Basilar artery | Basilar would cause bilateral findings or locked-in syndrome — not a unilateral syndrome |
| E) Left posterior cerebral artery (PCA) | PCA causes hemianopia and visual agnosia, not Broca aphasia |
Trap: Laterality trap — aphasia tells you the lesion is on the dominant (usually left) side even before you check the limbs.
Future alert: Face/arm > leg weakness + aphasia = dominant MCA stroke. Gaze looks toward the lesion.
Correct: B) Intravenous tissue plasminogen activator (tPA)
Concept: Thrombolysis eligibility — ischemic stroke within 4.5 hours, no exclusions Analysis
Why B: She is within the 4.5-hour window, CT excludes hemorrhage, and she has no major exclusion criteria (no recent surgery, platelet count adequate, INR normal, BP below the 185/110 threshold). IV tPA is indicated.
Discriminator: Within window + CT negative for bleed + no exclusions = give tPA before anything else.
| A) Aspirin 300 mg immediately | Aspirin is used when thrombolysis is NOT given; it is held for 24 hours after tPA |
| C) Full anticoagulation with warfarin | Anticoagulation is not acute stroke therapy for cardioembolic stroke; tPA comes first |
| D) Observe and reassess in 6 hours | Delaying thrombolysis wastes the time window — 'time is brain' |
| E) Start dual antiplatelet therapy | Dual antiplatelet is for TIA/minor stroke, not an eligible acute ischemic stroke |
Trap: Step-order trap — the examiner lists eligibility criteria to test whether you remember aspirin is held, not given, in the tPA pathway.
Future alert: Eligible acute ischemic stroke <4.5 h, CT clear → tPA 0.9 mg/kg (max 90), 10% bolus, rest over 1 h.
Correct: B) Admit for investigation and start dual antiplatelet therapy
Concept: TIA is a warning stroke — ABCD2 ≥4 mandates admission and dual antiplatelet Analysis
Why B: ABCD2: age ≥60 (0 — he is 54), BP ≥140/90 (1), unilateral weakness (2), duration ≥60 min — no (it was 20 min, so 1), diabetes (1). Total 5 → high-moderate risk. TIA carries a 10–20% stroke risk in 3 months; higher scores warrant admission, investigation, and dual antiplatelet (aspirin + clopidogrel) for 21 days.
Discriminator: Total ABCD2 = 5 (BP 1, weakness 2, duration 10–59 min 1, diabetes 1) → admit and treat.
| A) Discharge home with aspirin and outpatient follow-up | Score ≥4 is high risk — outpatient management is only for low-risk (0–3) TIA |
| C) Start warfarin immediately | No atrial fibrillation; antiplatelet, not anticoagulant, is the acute choice |
| D) Perform carotid endarterectomy today | Endarterectomy is for symptomatic carotid stenosis >70% and after imaging, not today |
| E) Only lifestyle advice and review in 6 months | TIA is a major stroke warning; lifestyle alone is insufficient at score 5 |
Trap: Calculation trap — they give you exactly the ABCD2 variables; compute the score, then apply the admission threshold.
Future alert: TIA: ABCD2 0–3 outpatient; ≥4 admit + aspirin + clopidogrel ×21 days.
Correct: C) Hypertensive lipohyalinosis with Charcot-Bouchard aneurysms
Concept: ICH location and mechanism — basal ganglia = hypertensive hemorrhage Recall
Why C: The putamen is the classic hypertensive hemorrhage site. Chronic hypertension causes lipohyalinosis of penetrating arterioles and Charcot-Bouchard microaneurysms, which rupture into the basal ganglia, thalamus, pons, or cerebellum.
Discriminator: Putamen location + longstanding HTN = hypertensive hemorrhage until proven otherwise.
| A) Aneurysm rupture | Aneurysm rupture causes subarachnoid blood in cisterns with thunderclap headache — not a putamen hematoma |
| B) Amyloid angiopathy | Amyloid angiopathy gives lobar hemorrhages in the elderly — not deep basal ganglia |
| D) Arteriovenous malformation | AVM typically bleeds in younger patients, often with preceding headache or seizures |
| E) Hemorrhagic transformation of an infarct | No prior infarct or symptom complex suggesting hemorrhagic transformation |
Trap: Location trap — deep (putamen/thalamus/pons) = hypertension; lobar = amyloid; cisternal = aneurysm.
Future alert: Hypertensive ICH: target SBP <140 within the first hour; reverse anticoagulation; avoid antiplatelets.
Correct: B) Lumbar puncture after 12 hours from onset to look for xanthochromia
Concept: SAH — CT negative but high suspicion → LP for xanthochromia after 12 hours Analysis
Why B: Thunderclap headache is the classic SAH presentation. CT sensitivity is 95% within 12 hours but falls to ~50% by day 7. In a high-suspicion patient with a negative CT, lumbar puncture after 12 hours from onset detects xanthochromia (bilirubin breakdown of RBCs), which takes 12 hours to develop and persists 2 weeks.
Discriminator: Normal CT does not rule out SAH; LP after 12 hours picks up xanthochromia.
| A) Discharge with analgesia and reassurance | Thunderclap headache cannot be safely discharged — SAH is lethal if missed |
| C) Repeat non-contrast CT in 24 hours | Repeating CT adds little; LP is the confirmatory test for a negative CT |
| D) Start beta-blockers for migraine | Migraine does not cause thunderclap headache — do not treat until SAH is excluded |
| E) Carotid Doppler | Carotid Doppler evaluates stenosis — irrelevant to this presentation |
Trap: Timing trap — LP too early (<12 h) misses xanthochromia; the examiner plants '3 hours after onset' to test the 12-hour rule.
Future alert: Thunderclap + normal CT → LP after 12 hours: xanthochromia = SAH; then angiography.
Correct: B) Anterior cerebral artery
Concept: ACA territory stroke — contralateral leg > arm weakness with incontinence Recall
Why B: ACA infarction produces contralateral leg-predominant weakness (medial motor cortex) plus urinary incontinence and frontal behavioral changes (apathy, abulia) from frontal lobe involvement.
Discriminator: Leg > arm weakness + incontinence + apathy = ACA signature triad.
| A) Middle cerebral artery | MCA affects face and arm more than leg and causes aphasia/neglect — not this pattern |
| C) Posterior cerebral artery | PCA causes hemianopia and visual agnosia — not leg weakness with incontinence |
| D) Vertebrobasilar system | Basilar causes bilateral/crossed brainstem syndromes, not pure medial frontal |
| E) Lateral medullary (PICA) | Wallenberg syndrome = ipsilateral Horner/ataxia + contralateral pain loss, vertigo — no leg weakness |
Trap: Distribution trap — 'leg more than arm' redirects you from the default MCA answer to ACA.
Future alert: Leg > arm weakness + urinary incontinence = ACA territory.
Correct: C) Oral anticoagulation (DOAC or warfarin to INR 2–3)
Concept: Cardioembolic stroke (AF) → anticoagulation for secondary prevention Interpretation
Why C: Atrial fibrillation with a documented atrial thrombus makes this a cardioembolic stroke. Anticoagulation — DOAC preferred, or warfarin with target INR 2–3 — is the secondary-prevention strategy of choice.
Discriminator: AF + atrial thrombus = cardioembolic mechanism → anticoagulate, not just antiplatelet.
| A) Aspirin 75 mg daily alone | Antiplatelet alone is inferior to anticoagulation for cardioembolic stroke |
| B) Aspirin + clopidogrel for 21 days, then clopidogrel | Dual antiplatelet is the TIA/minor-stroke regimen, not cardioembolic prevention |
| D) Carotid endarterectomy | Endarterectomy treats symptomatic carotid stenosis — not cardioembolism |
| E) Statins only, no antiplatelet or anticoagulant | Statins are an adjunct for all ischemic strokes but do not replace anticoagulation |
Trap: Mechanism trap — they list carotid stenosis options to catch you ignoring the AF and the thrombus.
Future alert: Cardioembolic stroke → DOAC (or warfarin INR 2–3). Start after the acute bleed risk window.
Correct: B) Lateral medullary syndrome (Wallenberg)
Concept: Wallenberg syndrome — PICA/vertebral artery — lateral medullary infarction Interpretation
Why B: The combination of ipsilateral facial pain/temp loss, Horner syndrome, ataxia, dysphagia/dysarthria, and contralateral body pain/temp loss is the classic lateral medullary (Wallenberg) syndrome from vertebral artery or PICA occlusion.
Discriminator: Ipsilateral face + Horner + ataxia; contralateral body pain/temp = lateral medullary thumbprint.
| A) Medial medullary syndrome | Medial medullary syndrome causes contralateral hemiparesis and loss of proprioception — not pain/temp and not Horner |
| C) Basilar artery occlusion with locked-in syndrome | Locked-in syndrome = quadriplegia with preserved vertical eye movements — she is ataxic, not tetraplegic |
| D) Right pontine hemorrhage | Pontine hemorrhage causes coma, pinpoint pupils, hyperthermia — not this crossed pattern |
| E) Cerebellar infarct with edema | Cerebellar infarct gives ataxia and nystagmus but not the crossed sensory dissociation or Horner |
Trap: Crossed-signs trap — the ipsilateral vs contralateral split is the whole question; learn it as one unit.
Future alert: Viva favorite: Wallenberg = ipsilateral face/Horner/ataxia + contralateral body pain-temp loss.
Correct: B) Ethosuximide
Concept: Childhood absence epilepsy — ethosuximide is first-line for pure absence Recall
Why B: Abrupt staring spells with eyelid flutter, no post-ictal confusion, triggered by hyperventilation, and 3 Hz spike-and-wave on EEG are childhood absence seizures. Ethosuximide is the first choice for pure absence epilepsy.
Discriminator: 3 Hz spike-and-wave + hyperventilation trigger + no post-ictal confusion = absence → ethosuximide.
| A) Carbamazepine | Carbamazepine is for focal seizures and can worsen absence/myoclonic seizures |
| C) Phenytoin | Phenytoin worsens absence seizures and has a narrow therapeutic index |
| D) Levetiracetam | Levetiracetam is a broad-spectrum alternative, not the first choice for pure absence |
| E) Gabapentin | Gabapentin is not indicated for absence epilepsy |
Trap: Drug-choice trap — 'staring spells in a child' should point to absence, not generalized tonic-clonic, so the answer is ethosuximide, not valproate/carbamazepine.
Future alert: Absence epilepsy → ethosuximide first; avoid carbamazepine and phenytoin.
Correct: B) IV lorazepam 0.1 mg/kg (max 4 mg)
Concept: Status epilepticus — first-line benzodiazepine Recall
Why B: Status epilepticus is defined as a seizure lasting >5 minutes or repeated seizures without recovery of consciousness. The first-line agent is a benzodiazepine — IV lorazepam 0.1 mg/kg (max 4 mg) is preferred when IV access exists.
Discriminator: Seizure >5 min = status protocol; first line is a benzodiazepine, then repeat once, then second-line agents.
| A) IV phenytoin 20 mg/kg | Phenytoin is second-line (10–20 min), given only if benzodiazepines fail |
| C) IV valproate | Valproate is a second-line/alternate agent, not first-line |
| D) IV phenobarbital | Phenobarbital is second-line, not first |
| E) Rectal paracetamol | Paracetamol treats fever — irrelevant to terminating the seizure |
Trap: Order trap — the protocol is time-locked: 0–5 min stabilization, 5–10 min benzodiazepine, 10–20 min phenytoin. The '8 minutes' in the stem selects lorazepam.
Future alert: Status protocol: lorazepam 0.1 mg/kg → repeat once → phenytoin 20 mg/kg → ICU infusion.
Correct: B) Neurocysticercosis
Concept: Neurocysticercosis — acquired epilepsy in developing countries with ring-enhancing lesion Interpretation
Why B: A young adult from a rural area with new-onset seizures and a single ring-enhancing lesion is neurocysticercosis until proven otherwise — the most common cause of acquired epilepsy in developing countries, caused by Taenia solium larvae.
Discriminator: Seizures + ring-enhancing lesion + rural residence = the NCC triad in this setting.
| A) Brain abscess | Abscess would usually cause fever, focal deficits, and pro-encephalopathic illness — no fever here |
| C) Primary brain tumor | Tumor is possible but NCC is by far the most common cause of this exact picture in a rural young adult |
| D) Tuberculoma | Tuberculoma typically has evidence of systemic TB and often basal exudates — less likely first choice |
| E) Cerebral aneurysm | Aneurysm presents with thunderclap hemorrhage, not a ring-enhancing lesion |
Trap: Setting trap — the examiner uses 'rural area' to anchor you to the endemic diagnosis; don't default to tumor.
Future alert: Ring-enhancing lesion + seizures in a rural young adult → albendazole + steroids + antiepileptic.
Correct: B) Switch to lamotrigine or levetiracetam before conception with slow titration
Concept: Valproate teratogenicity — avoid in women of childbearing age Analysis
Why B: Valproate is teratogenic (neural tube defects) and is the most important antiepileptic to avoid in pregnancy. In JME, lamotrigine or levetiracetam are safer alternatives, switched with slow titration before conception.
Discriminator: JME + planned pregnancy + current valproate = switch to a teratogen-safe agent pre-conception.
| A) Continue valproate at the same dose | Continuing valproate through planned pregnancy exposes the fetus to neural tube defect risk |
| C) Stop all antiepileptics immediately | Abruptly stopping AEDs risks status and breakthrough seizures — unsafe |
| D) Add carbamazepine | Carbamazepine is poor for myoclonic seizures and can worsen them |
| E) Switch to phenytoin | Phenytoin is also teratogenic and worsens myoclonus — no advantage |
Trap: Population trap — the patient is female and planning pregnancy; 'best efficacy' now yields to teratogenicity.
Future alert: Women of childbearing age: avoid valproate; lamotrigine/levetiracetam are safer.
Correct: C) Non-compliance with antiepileptics
Concept: Status epilepticus causes — non-compliance tops the list in known epileptics Recall
Why C: In known epileptics, the most common cause of breakthrough status is non-compliance with antiepileptic medication. (In Pakistan, the common causes are non-compliance, hypoglycemia, CNS infections, neurocysticercosis, and stroke.)
Discriminator: 'Stopped his tablets 3 days ago' is the direct answer — non-compliance is the leading cause.
| A) Hypoglycemia | Hypoglycemia is a common cause but the stem tells you he stopped his drugs — that is the cause |
| B) CNS infection | CNS infection causes new-onset status, not typically the missed-dose breakthrough |
| D) New structural lesion | No focal deficit or imaging clue suggesting a new lesion |
| E) Drug interaction | Carbamazepine enzyme induction matters for other drugs — not his breakthrough cause |
Trap: Mnemonic trap — MINES (Metabolic, Infections, Non-compliance, Epilepsy, Structural) — the stem hands you the non-compliance branch.
Future alert: Breakthrough status in a known epileptic: ask about missed doses first.
Correct: B) Bradykinesia
Concept: Parkinson disease — bradykinesia is essential for diagnosis Recall
Why B: Bradykinesia (slowness of movement) is ESSENTIAL for the diagnosis of Parkinson disease. The other cardinal features — resting tremor, rigidity, postural instability — support it, but bradykinesia is the required element (BRAD mnemonic).
Discriminator: 'Essential' is the operative word — the stem tests the one feature that must be present.
| A) Resting tremor | Resting tremor is classic but can be absent in up to 30% of PD patients |
| C) Postural instability | Postural instability is a late feature and not essential for diagnosis |
| D) Cogwheel rigidity | Rigidity is common but not essential |
| E) Masked facies | Masked facies is a supportive sign, not a diagnostic requirement |
Trap: Keyword trap — 'ESSENTIAL' is capitalized in the source for a reason; the exam mirrors that emphasis.
Future alert: PD diagnosis: bradykinesia is essential; plus ≥1 of resting tremor, rigidity, postural instability.
Correct: B) Essential tremor
Concept: Essential tremor — action tremor with family history, no parkinsonism Interpretation
Why B: Action tremor (worse with holding/writing), positive family history, absence of bradykinesia and rigidity, and improvement with alcohol are classic essential tremor. It is the most common movement disorder overall.
Discriminator: Worse with action + family history + no bradykinesia = essential tremor.
| A) Parkinson disease | PD is a resting tremor with bradykinesia — both absent here |
| C) Wilson disease | Wilson disease presents young with Kayser-Fleischer rings and hepatic signs |
| D) Dystonic tremor | Dystonic tremor occurs with abnormal postures and is often task-specific |
| E) Cerebellar tremor | Cerebellar tremor is an intention tremor with ataxia and other cerebellar signs |
Trap: Action-vs-rest trap — 'worse when holding a cup' immediately separates essential tremor from PD.
Future alert: Essential tremor → propranolol 20–80 mg BD or primidone first-line.
Correct: B) Botulinum toxin injection
Concept: Focal dystonia (torticollis) — botulinum toxin is first-line Recall
Why B: Torticollis is a focal dystonia — sustained involuntary muscle contraction causing abnormal posture. Botulinum toxin injection into the affected muscles is the first-line treatment for focal dystonia.
Discriminator: Focal dystonia + abnormal posture = botulinum toxin first-line.
| A) Levodopa-carbidopa | Levodopa is for Parkinson disease — no bradykinesia or rigidity here |
| C) Propranolol | Propranolol treats essential tremor, not dystonia |
| D) Deep brain stimulation | DBS is reserved for severe generalized dystonia refractory to other measures |
| E) Tetrabenazine | Tetrabenazine is used for chorea (e.g., Huntington disease), not focal dystonia |
Trap: Classification trap — 'neck twisting' is dystonia, not tremor; choose the dystonia pathway.
Future alert: Focal dystonia → botulinum toxin; severe/generalized → anticholinergics or DBS.
Correct: B) Genetic testing showing CAG repeat expansion (>36 repeats) in the huntingtin gene
Concept: Huntington disease — chorea + dementia + psychiatric features, CAG repeat diagnosis Recall
Why B: The triad of chorea, cognitive decline, and psychiatric symptoms with a positive family history is Huntington disease — autosomal dominant CAG repeat expansion in the huntingtin gene on chromosome 4 (>36 repeats). Genetic testing confirms.
Discriminator: Family history (mother in psychiatric institution) + chorea + dementia = HD → genetic testing.
| A) MRI showing caudate atrophy alone | Caudate atrophy on imaging supports HD but is not diagnostic confirmation |
| C) Serum copper and ceruloplasmin | Copper studies diagnose Wilson disease — age and psychiatric heredity don't fit |
| D) DAT scan | DAT scan assesses dopamine transporter — used in parkinsonism |
| E) EEG with 3 Hz spike-and-wave | 3 Hz spike-and-wave is absence epilepsy, not HD |
Trap: Heredity trap — the family history is buried in 'mother died in a psychiatric institution'; that is the Huntington clue.
Future alert: HD triad: chorea + dementia + psychiatric. Confirm with CAG repeat count; treat symptoms only.
Correct: B) COMT inhibitors (entacapone) may reduce off-time by decreasing levodopa breakdown
Concept: Levodopa complications — motor fluctuations; COMT inhibitors extend on-time Interpretation
Why B: Long-term levodopa causes motor fluctuations (wearing-off, on-off) and peak-dose dyskinesias. Adjunctive COMT inhibitors (entacapone, tolcapone) reduce peripheral levodopa breakdown and extend on-time. DBS is actually an option for refractory fluctuations.
Discriminator: Wearing-off + peak-dose dyskinesia = classic levodopa complication; entacapone is the adjunct.
| A) Levodopa should be stopped permanently because dyskinesias mean toxicity | Levodopa is not stopped for dyskinesias — it is managed with dose splitting, adjuncts, or DBS |
| C) Deep brain stimulation is contraindicated in motor fluctuations | DBS (STN) is precisely for refractory motor fluctuations — the statement is backwards |
| D) Dopamine agonists work faster than levodopa and should replace it | Dopamine agonists do not replace levodopa in advanced disease; they are used early to delay fluctuations |
| E) Rasagiline reverses dyskinesia | Rasagiline is an MAO-B inhibitor used early, not a dyskinesia treatment |
Trap: Management trap — the question rewards the mechanism-based adjunct (extend levodopa half-life), not abandonment.
Future alert: Wearing-off → entacapone/tolcapone; refractory → DBS. Never abruptly stop levodopa.
Correct: B) Severe attacks are best treated with sumatriptan, a 5-HT1B/1D agonist
Concept: Migraine acute therapy — triptans for severe attacks Interpretation
Why B: Migraine with unilateral throbbing pain, nausea, photophobia/phonophobia, and activity-aggravated attacks meets ICHD-3 criteria. Acute treatment is severity-based: mild — NSAIDs early; moderate — NSAID + antiemetic; severe — triptan (sumatriptan 50–100 mg oral or 6 mg SC).
Discriminator: 'Severe attacks' in the stem selects the triptan branch of the severity ladder.
| A) NSAIDs taken late in the attack are most effective | NSAIDs must be taken EARLY in an attack to be effective — late dosing is the trap |
| C) Triptans are the first choice in pregnancy | Triptans are contraindicated in pregnancy — that is listed among the contraindications |
| D) Ergotamine should be combined with sumatriptan for synergy | Ergotamine within 24 hours of a triptan is contraindicated, never combined |
| E) Analgesics should be used more than 15 days monthly to prevent recurrence | Overuse (>10–15 days/month) causes medication overuse headache |
Trap: Severity ladder trap — the stem deliberately omits severity in one option to test the tiered protocol.
Future alert: Migraine: mild NSAID early; moderate + metoclopramide; severe triptan; avoid >10–15 days/month.
Correct: A) Propranolol
Concept: Migraine prophylaxis — propranolol has the most evidence among first-line options Recall
Why A: Prophylaxis is indicated at ≥2 attacks/month with disability. Beta-blockers — propranolol — are first-line with the most evidence. (Topiramate, amitriptyline, valproate are alternatives; valproate is teratogenic in a woman of childbearing age.)
Discriminator: First-line prophylactic with 'most evidence' = propranolol; she is young and female so valproate is bad choice.
| B) Valproate | Valproate is effective but teratogenic — a poor choice in a 28-year-old woman |
| C) Topiramate | Topiramate is an alternative option, not the most-evidence first-line |
| D) Amitriptyline | Amitriptyline is useful (also for tension headache) but not the top first-line |
| E) CGRP antibody erenumab | Erenumab is very effective but expensive, not routine first-line |
Trap: Population trap — the young-female detail plus 'most evidence' steers away from valproate despite efficacy.
Future alert: Prophylaxis at ≥2 disabling attacks/month: propranolol first, topiramate/amitriptyline alternatives.
Correct: A) 100% oxygen via non-rebreather mask
Concept: Cluster headache — 100% oxygen is first-line acute treatment Recall
Why A: Severe unilateral periorbital pain at the same time daily, autonomic features (lacrimation, conjunctival injection, ptosis), and pacing behavior are cluster headache. Acute treatment is 100% oxygen 15 L/min via non-rebreather ×15–20 min (first-line) or subcutaneous/intranasal sumatriptan.
Discriminator: 'Alarm clock headache' + pacing + ipsilateral autonomic features = cluster → oxygen first.
| B) Oral ibuprofen | NSAIDs are ineffective for cluster attacks — pain is excruciating and brief |
| C) Paracetamol with codeine | Simple analgesics do not touch cluster attacks |
| D) Oral propranolol | Propranolol is for migraine prophylaxis, not acute cluster |
| E) Sumatriptan 50 mg oral | ORAL sumatriptan is too slow; only SC or intranasal is recommended for cluster |
Trap: Autonomic trap — the eye redness/tearing makes examinees think of a red-eye emergency; it is cluster.
Future alert: Cluster: acute 100% oxygen + SC sumatriptan; prophylaxis verapamil 240–360 mg.
Correct: B) Tension-type headache
Concept: Tension-type headache — bilateral band-like pressure, no migrainous features Interpretation
Why B: Bilateral band-like pressure, mild-moderate severity, no nausea/vomiting, no photophobia/phonophobia, not aggravated by activity, stress-linked — tension-type headache. Duration 30 minutes to 7 days fits.
Discriminator: Bilateral + pressure quality + absent migrainous features + stress = tension-type.
| A) Migraine without aura | Migraine requires ≥2 of unilateral/pulsating/mod-severe/activity-aggravated plus nausea or photo+phonophobia — none present |
| C) Cluster headache | Cluster is unilateral periorbital, excruciating, with autonomic features — wholly different |
| D) Medication overuse headache | MOH requires frequent acute medication use (>10–15 days/month) — not described |
| E) Subarachnoid hemorrhage | SAH is thunderclap — sudden and maximal at onset, not a 4-week pressure headache |
Trap: New-headache trap — 'NEW headache at 55' is a red flag for secondary causes, but the phenotype itself is classic tension-type; no SCARY features are present.
Future alert: Tension-type: NSAIDs acute; amitriptyline 10–75 mg at night if frequent.
Correct: B) Elevate head 30°, hyperventilate to target pCO2 35–40 mmHg, give mannitol 0.25–1 g/kg
Concept: Raised ICP emergency — head elevation, controlled hyperventilation, osmotherapy Analysis
Why B: The Cushing triad (hypertension, bradycardia, irregular breathing) signals dangerous raised ICP with brainstem compression. Immediate measures: elevate head 30°, hyperventilation to pCO2 35–40 mmHg (temporary vasoconstriction), mannitol 20% 0.25–1 g/kg or hypertonic saline, and treat the underlying cause.
Discriminator: Cushing triad = emergency; the multi-part management stem selects the multi-part correct option.
| A) Give IV fluids rapidly and keep flat | Fluids flat lower venous drainage and raise ICP further; hypotension/hypoxia/fever all worsen ICP |
| C) Start oral steroids only | Steroids help vasogenic edema from tumor but are not the immediate ICP emergency alone |
| D) Give sublingual nifedipine for the blood pressure | Lowering BP in raised ICP can compromise cerebral perfusion; treatment targets ICP first |
| E) Needle decompression of the ventricles at the bedside | Bedside ventricular decompression is not a first-line ward maneuver |
Trap: Cushing trap — the vital signs (hypertension + bradycardia + irregular breathing) are the emergency cue the stem buries.
Future alert: Raised ICP: head 30°, pCO2 35–40, mannitol/hypertonic saline, treat cause. Avoid hypotension and hypoxia.
Correct: B) CN VI palsy in raised ICP is a false localizing sign because CN VI has the longest intracranial course
Concept: False localizing sign — CN VI palsy in raised ICP Recall
Why B: CN VI has the longest intracranial course, so any cause of raised ICP can compress it regardless of lesion location. It is the classic FALSE LOCALIZING SIGN — it does not indicate where the lesion is.
Discriminator: Left frontal lesion + right CN VI palsy = the VI palsy is non-localizing.
| A) The CN VI palsy localizes the tumor to the pons — imaging is wrong | The tumor localization is correct; it is the CN VI palsy that is misleading |
| C) The CN VI palsy is caused by direct tumor invasion | Direct invasion would require the tumor to contact the nerve territory — it does not |
| D) The diplopia is due to a cerebellar lesion | Diplopia here is from VI palsy, not cerebellum |
| E) CN VI palsy cannot occur with raised ICP | CN VI palsy is one of the most common signs of raised ICP |
Trap: Viva-answer trap — 'false localizing sign' is a verbatim viva favorite; the whole answer is the mechanism.
Future alert: False localizing sign = CN VI palsy with raised ICP. Longest intracranial course.
Correct: B) Blood cultures, then start empirical antibiotics immediately, adding dexamethasone 15 minutes before or with the first dose, then LP if no contraindications
Concept: Bacterial meningitis — antibiotics before LP, dexamethasone timing Analysis
Why B: In suspected bacterial meningitis, blood cultures are drawn and empirical antibiotics are started IMMEDIATELY — never wait for LP or CT. Dexamethasone 10 mg IV is given 15 minutes BEFORE or WITH the first antibiotic dose, then LP proceeds if no contraindications (no papilledema, no focal signs, no low GCS here).
Discriminator: 'Do not wait for LP or CT' is the protocol; alert patient without papilledema/focal signs = safe LP after antibiotics.
| A) CT head first, then LP, then antibiotics | CT is only needed before LP if there are contraindications — none exist here; antibiotics should not wait |
| C) Start acyclovir first because of headache | Acyclovir treats HSV encephalitis — this is classic bacterial meningitis, not encephalitis |
| D) Observe and reassess in 6 hours | Observation wastes the window; bacterial meningitis is rapidly fatal if untreated |
| E) LP first, then antibiotics only after CSF report | Waiting for CSF before antibiotics is exactly what the protocol forbids |
Trap: Order trap — the exam loves testing that antibiotics come before LP and that dexamethasone precedes the antibiotic.
Future alert: Suspected bacterial meningitis: blood cultures → antibiotics NOW + dexamethasone 15 min before/with → LP if safe.
Correct: B) Isoniazid, rifampicin, pyrazinamide, ethambutol + pyridoxine with dexamethasone, for 12 months
Concept: Tuberculous meningitis — RIPE + pyridoxine + steroids, 12 months Interpretation
Why B: Subacute meningitis with lymphocytic pleocytosis, high protein, low glucose, and positive GeneXpert is TB meningitis. Treatment: RIPE intensive phase 2 months, then INH+rifampicin continuation 10 months (total 12 months — longer than pulmonary TB), plus pyridoxine and dexamethasone for ALL patients.
Discriminator: Lymphocytic CSF + very low glucose + high protein + positive GeneXpert = TBM → 12-month RIPE + steroids.
| A) Ceftriaxone + vancomycin for 14 days | Ceftriaxone/vancomycin is bacterial meningitis therapy — this is TB |
| C) Acyclovir for 21 days | Acyclovir treats HSV encephalitis, not TB meningitis |
| D) Amphotericin B for 14 days | Amphotericin treats fungal (cryptococcal) meningitis — not confirmed here |
| E) Antituberculous therapy for 6 months only | 6 months is pulmonary TB duration; TBM needs 12 months |
Trap: Duration trap — TB meningitis is 12 months, not the 6-month pulmonary regimen; the examiner counts on the slip.
Future alert: TBM: RIPE 2 mo + INH/RIF 10 mo = 12 mo total; dexamethasone for all; pyridoxine with INH.
Correct: C) Enterovirus (viral meningitis)
Concept: Viral meningitis — lymphocytic pleocytosis with NORMAL glucose Interpretation
Why C: Viral meningitis classically shows clear CSF, lymphocytic pleocytosis, normal or mildly raised protein, and NORMAL glucose. Enteroviruses cause 80% of viral meningitis. Bacterial meningitis would show polymorphs and low glucose; TB shows very low glucose with very high protein.
Discriminator: Lymphocytic CSF + normal glucose + mild protein = viral pattern.
| A) Streptococcus pneumoniae | Pneumococcal meningitis is pyogenic: polymorphs, very low glucose, high protein, severe illness |
| B) Neisseria meningitidis | Meningococcal meningitis is also pyogenic with low glucose |
| D) Mycobacterium tuberculosis | TB shows very low glucose (<40% serum), very high protein (100–500), and longer subacute course |
| E) Herpes simplex virus encephalitis | HSV encephalitis has altered consciousness, seizures, and focal signs — she is alert with meningism |
Trap: Glucose trap — 'normal CSF glucose' is the whole question; it separates viral from bacterial/TB.
Future alert: CSF: lymphocytes + normal glucose = viral; polymorphs + low glucose = bacterial; lymphs + VERY low glucose + high protein = TB.
Correct: B) CSF HSV PCR; acyclovir 10 mg/kg IV TDS
Concept: HSV encephalitis — temporal lobe involvement, CSF PCR gold standard, acyclovir immediately Analysis
Why B: Fever + altered behavior + seizures + bilateral temporal lobe lesions = herpes simplex encephalitis until proven otherwise. CSF PCR for HSV DNA is the gold standard test. Acyclovir 10 mg/kg IV TDS must be started IMMEDIATELY — empirically, without waiting for confirmation.
Discriminator: Behavioral change + seizures + temporal lobe FLAIR = HSE → acyclovir now, PCR to confirm.
| A) CSF bacterial culture; ceftriaxone | No meningeal signs and CSF is not the picture of bacterial meningitis |
| C) CSF AFB smear; antituberculous therapy | TBM would be subacute with severe CSF abnormalities and basal predilection, not temporal lobes |
| D) EEG; phenytoin | EEG shows PLEDs but is not diagnostic; phenytoin treats seizures but not the cause |
| E) Serum VDRL; penicillin | Neurosyphilis causes different syndromes; temporal lobe FLAIR is the HSE signature |
Trap: Imaging trap — bilateral temporal lobe FLAIR hyperintensity is the HSE card; do not be distracted by the seizures.
Future alert: HSE: start acyclovir immediately if suspected; CT is often normal early — MRI is the imaging choice.
Correct: B) Rifampicin 600 mg BD × 2 days, or ciprofloxacin 500 mg single dose, or ceftriaxone 250 mg IM single dose
Concept: Meningococcal meningitis — chemoprophylaxis for close contacts Recall
Why B: Household and close contacts of a patient with Neisseria meningitidis meningitis require chemoprophylaxis: rifampicin 600 mg BD ×2 days, OR ciprofloxacin 500 mg single dose, OR ceftriaxone 250 mg IM single dose. Household contacts are at increased risk.
Discriminator: 'Husband and two children... same house' = close contacts → chemoprophylaxis is required.
| A) No prophylaxis needed once the index patient has received 24 hours of antibiotics | Prophylaxis is still indicated for close contacts even after the index patient is treated |
| C) Give all contacts the same IV ceftriaxone course for 7 days | Close contacts get prophylaxis, not a full therapeutic course |
| D) Give prophylactic acyclovir | Acyclovir treats HSV — irrelevant to meningococcal contacts |
| E) Give the meningococcal vaccine only to the children | Vaccination of contacts is adjunctive; antibiotics are the immediate prophylaxis |
Trap: Extending-therapy trap — the examiner offers 'treat everyone' which sounds generous but is wrong; prophylaxis is short.
Future alert: Meningococcal contacts: rifampicin 600 mg BD ×2 days / ciprofloxacin 500 mg single / ceftriaxone 250 mg IM.
Correct: A) Japanese encephalitis; supportive care only — no specific antiviral
Concept: Japanese encephalitis — endemic rural monsoon encephalitis, supportive management Interpretation
Why A: Rural child, monsoon season, encephalitis with parkinsonian features (mask-like facies, rigidity, tremor) and bilateral thalamic lesions is Japanese encephalitis, transmitted by Culex mosquitoes (reservoir: pigs/water birds). There is no specific antiviral — management is supportive (seizure control, ICP care, ventilation).
Discriminator: Monsoon + rural + parkinsonian features + thalamic MRI = JE; no antiviral exists.
| B) HSV encephalitis; acyclovir | HSV targets temporal lobes, not thalami, and has acyclovir as specific therapy |
| C) Cerebral malaria; artesunate | Cerebral malaria needs falciparum exposure and often retinopathy/anemia; thalamic lesions are not its signature |
| D) TB meningitis; RIPE | TBM is subacute with basal exudates and cranial nerve palsies — not monsoon encephalitis |
| E) Bacterial meningitis; ceftriaxone | Bacterial meningitis causes meningism with pyogenic CSF; this is parenchymal with parkinsonism |
Trap: Season/location trap — monsoon + rural + parkinsonism = JE, and the catch is that treatment is SUPPORTIVE.
Future alert: JE: vaccine exists; acute management is supportive. Bilateral thalamic lesions are characteristic.
Correct: B) Multiple sclerosis
Concept: MS — relapsing remitting, disseminated in space and time Interpretation
Why B: Neurological symptoms separated in space (optic neuritis, spinal cord, diplopia/INO) and time (multiple episodes in a year) in a young woman are multiple sclerosis — lesions disseminated in space AND time. RAPD is the optic neuritis residue; brisk reflexes show UMN involvement.
Discriminator: Young woman + relapses in different CNS territories + RAPD = MS.
| A) Neuromyelitis optica | NMO (anti-AQP4) typically causes severe bilateral optic neuritis and longitudinally extensive transverse myelitis; recurrent small multi-territory episodes favor MS |
| C) Guillain-Barré syndrome | GBS is acute, monophasic, ascending, areflexic — not relapsing with UMN signs |
| D) Vitamin B12 deficiency | B12 deficiency gives chronic myelopathy with sensory ataxia — not relapsing episodes |
| E) Stroke | Stroke is acute and monophasic, not a year of relapsing symptoms |
Trap: Dissemination trap — the episodes across different systems and times is the MS diagnostic engine; RAPD confirms prior optic nerve demyelination.
Future alert: MS: MRI (dissemination in space/time), CSF oligoclonal bands; relapse → IV methylprednisolone 1 g ×3–5 days.
Correct: A) High-dose IV methylprednisolone 1 g daily × 3–5 days
Concept: MS acute relapse — IV methylprednisolone shortens relapse duration Recall
Why A: High-dose IV methylprednisolone 1 g daily for 3–5 days shortens the duration of a disabling relapse. It does NOT alter long-term prognosis and is reserved for disabling relapses. DMT (interferon, natalizumab etc.) controls the disease course, not the acute relapse.
Discriminator: 'Disabling acute episode' = relapse treatment with pulse steroids; DMT is for long-term.
| B) Oral baclofen only | Baclofen treats spasticity, not the acute inflammatory relapse |
| C) Interferon-beta dose escalation | Interferon-beta is a disease-modifying therapy, not acute relapse treatment |
| D) Start natalizumab immediately as the primary response | Natalizumab is second-line DMT for severe disease, not first response to a relapse |
| E) Conservative physiotherapy only | Physiotherapy is adjunctive; an acute disabling relapse warrants pulse steroids |
Trap: Relapse-vs-DMT trap — the examiner mixes long-term drugs into an acute-relapse question.
Future alert: Acute disabling MS relapse → IV methylprednisolone 1 g/day ×3–5 days (does not change long-term prognosis).
Correct: B) Lhermitte sign and Uhthoff phenomenon
Concept: Lhermitte sign (neck flexion shock) and Uhthoff phenomenon (heat worsens symptoms) Recall
Why B: Electric-shock sensation down the spine with neck flexion is the Lhermitte sign. Worsening of MS symptoms with heat or exercise (hot bath, fever) is the Uhthoff phenomenon.
Discriminator: The stem describes both in order: neck-flexion shock first, heat worsening second.
| A) Uhthoff phenomenon and Lhermitte sign | Reversed pairing — the shock is Lhermitte, the heat worsening is Uhthoff |
| C) Marcus Gunn pupil and Dawson fingers | Marcus Gunn pupil is the RAPD of optic neuritis; Dawson fingers are periventricular MRI plaques — not these phenomena |
| D) Oligoclonal bands and black holes | Oligoclonal bands and black holes are investigation findings, not symptoms |
| E) Charcot triad and Millard-Gubler syndrome | Charcot triad belongs to cholangitis (or advanced MS ataxia triad); Millard-Gubler is a pontine syndrome |
Trap: Pairing trap — both names appear in one option, reversed; the exam tests exact attribution.
Future alert: Lhermitte = neck flexion electric shock. Uhthoff = heat worsens symptoms. Both classic MS.
Correct: C) Interferon-beta (IFN-β)
Concept: MS DMT in Pakistan — IFN-β is the most commonly used due to affordability Recall
Why C: Interferon-beta is the most commonly used disease-modifying therapy in Pakistan because it is more affordable than oral agents and far cheaper than the biologics (natalizumab, ocrelizumab, alemtuzumab). Side effects: flu-like symptoms, depression, hepatotoxicity.
Discriminator: 'Most common in Pakistan' + affordability = IFN-β; the biologics are expensive and limited.
| A) Natalizumab | Natalizumab is a second-line biologic with PML risk — expensive and limited in Pakistan |
| B) Ocrelizumab | Ocrelizumab is an anti-CD20 biologic — very expensive |
| D) Fingolimod | Fingolimod is an oral second-line agent, costly and requires first-dose cardiac monitoring |
| E) Alemtuzumab | Alemtuzumab is an anti-CD52 biologic reserved for refractory disease |
Trap: Context trap — the question is not 'most effective' but 'most used in Pakistan'; affordability decides.
Future alert: MS DMT in Pakistan: IFN-β first (affordable); oral agents increasingly available; biologics limited.
Correct: C) Guillain-Barré syndrome
Concept: GBS — ascending paralysis with areflexia 2–4 weeks after infection Interpretation
Why C: Ascending symmetric weakness with areflexia after a diarrheal illness (Campylobacter jejuni is the most common antecedent) is Guillain-Barré syndrome. Areflexia is the hallmark; sensory signs are minimal.
Discriminator: Ascending weakness + areflexia + post-diarrheal illness = GBS.
| A) Multiple sclerosis | MS is CNS with UMN signs and hyperreflexia, not acute ascending areflexic paralysis |
| B) Transverse myelitis | Transverse myelitis gives a sensory level and UMN signs with bladder dysfunction |
| D) Myasthenia gravis | MG is fatigable, fluctuating, with ocular/bulbar prominence — not ascending areflexia |
| E) Tetanus | Tetanus causes rigidity and spasms, not flaccid ascending weakness |
Trap: Antecedent trap — the diarrheal illness is the GBS prodrome card; Campylobacter is the most common trigger.
Future alert: GBS: ascending paralysis + areflexia + antecedent infection → IVIg or plasma exchange within 2 weeks.
Correct: B) Start IVIg 0.4 g/kg/day × 5 days and prepare for intubation as VC <15–20 mL/kg
Concept: GBS respiratory monitoring and immunotherapy — IVIg when unable to walk, intubate at low VC Analysis
Why B: She cannot walk unaided (indication for immunotherapy) and VC <15–20 mL/kg is the intubation threshold. IVIg 0.4 g/kg/day ×5 days (total 2 g/kg) or plasma exchange is equally effective; steroids are NOT effective in GBS.
Discriminator: VC 14 mL/kg crosses the intubation line; inability to walk triggers IVIg — both in option B.
| A) Observe for another 48 hours | Observation wastes the treatment window and risks respiratory arrest at this VC |
| C) Give high-dose oral prednisolone | Steroids are ineffective in GBS — a core teaching point |
| D) Start aspirin 300 mg daily | Aspirin has no role in GBS |
| E) Start beta-blockers for the tachycardia | Beta-blockers are avoided in GBS — they can worsen autonomic instability |
Trap: Threshold trap — VC <15–20 mL/kg and NIF >−30 cmH2O are the intubation numbers; the stem gives you 14 to trigger it.
Future alert: GBS: intubate if VC <15–20 mL/kg, NIF >−30, or bulbar failure; IVIg/plasma exchange within 2 weeks; NO steroids.
Correct: B) Anti-GQ1b
Concept: Miller Fisher syndrome — anti-GQ1b antibodies Recall
Why B: The triad of ataxia, areflexia, and ophthalmoplegia is Miller Fisher syndrome, a GBS variant associated with anti-GQ1b antibodies. Albuminocytologic dissociation (elevated protein, normal WBC) in CSF supports the diagnosis.
Discriminator: Ataxia + areflexia + ophthalmoplegia = Miller Fisher → anti-GQ1b.
| A) Anti-AChR | Anti-AChR is myasthenia gravis |
| C) Anti-MuSK | Anti-MuSK is a myasthenia variant with bulbar prominence |
| D) Anti-Hu | Anti-Hu is a paraneoplastic antibody associated with small cell lung cancer |
| E) Anti-aquaporin-4 | Anti-aquaporin-4 is neuromyelitis optica |
Trap: Variant-antibody trap — the exam pairs each GBS variant with its signature antibody; Miller Fisher = GQ1b.
Future alert: Miller Fisher triad: ataxia, areflexia, ophthalmoplegia → anti-GQ1b; better prognosis than classic GBS.
Correct: A) Myasthenia gravis
Concept: MG — fatigable weakness, ptosis/diplopia, improves with rest Interpretation
Why A: Fluctuating weakness that worsens with use (evening ptosis, chewing fatigue) and improves with rest is myasthenia gravis — autoimmune antibodies against acetylcholine receptors. No pupil involvement and preserved reflexes are characteristic.
Discriminator: Fatigability + diurnal fluctuation + ocular onset + normal pupils = MG.
| B) Multiple sclerosis | MS gives UMN signs and relapses in CNS territories — not fatigable ocular weakness |
| C) Guillain-Barré syndrome | GBS is acute ascending areflexic paralysis — not fluctuating ptosis |
| D) Bell palsy | Bell palsy is acute unilateral LMN facial weakness with forehead involvement |
| E) Third nerve palsy | CN III palsy has a fixed eye position and (if compressive) a dilated pupil |
Trap: Diurnal trap — 'worse in the evening, better after rest' is the MG fingerprint worth the whole question.
Future alert: MG: pyridostigmine 60 mg TDS–QID; prednisolone 0.5–1 mg/kg; all patients need chest imaging (thymoma).
Correct: B) Thymic hyperplasia
Concept: MG thymus — thymic hyperplasia in young patients, thymoma in older Recall
Why B: ALL MG patients need chest imaging. Thymic hyperplasia occurs in 60–70% of young MG patients (especially young women); thymoma occurs in only 10–15% (more in older males).
Discriminator: Young woman → hyperplasia is the statistically dominant finding.
| A) Thymoma | Thymoma is found in 10–15%, particularly older men — not the most likely finding here |
| C) Normal thymus | Normal thymus occurs in 15–20% — less common than hyperplasia |
| D) Thymic cyst | Thymic cyst is not a recognized MG association pattern |
| E) Thymic carcinoid | Thymic carcinoid is rare and not the classic MG association |
Trap: Percentage trap — 60–70% (hyperplasia) vs 10–15% (thymoma); the examiner tests the bigger number.
Future alert: MG chest imaging mandatory: hyperplasia 60–70% young; thymoma 10–15% older. Thymoma = absolute thymectomy indication.
Correct: B) Intubation and ICU care; stop pyridostigmine; start IVIg or plasmapheresis; treat the precipitant
Concept: Myasthenic crisis — intubate early, stop pyridostigmine, rapid immunotherapy, treat infection Analysis
Why B: VC <15–20 mL/kg with respiratory failure = myasthenic crisis → intubation without waiting for hypoxia. Pyridostigmine is stopped (secretions worsen with cholinergics), IVIg or plasmapheresis started immediately, and the precipitant (infection here) treated.
Discriminator: Infection + low VC + pooling secretions = crisis protocol: ventilate, stop pyridostigmine, IVIg/pheresis.
| A) Give her a double dose of pyridostigmine immediately | More pyridostigmine worsens secretions and risks cholinergic crisis — it is stopped, not doubled |
| C) Start atropine only | Atropine treats cholinergic overdose symptoms but not the crisis |
| D) Give neostigmine and observe on the ward | Neostigmine adds cholinergic load — dangerous in crisis |
| E) Start high-dose oral steroids alone | Steroids can worsen MG initially and act too slowly for acute crisis |
Trap: Crisis trap — the classic error is giving more pyridostigmine; the correct protocol removes it.
Future alert: Myasthenic crisis: intubate early (VC <15–20), stop pyridostigmine, IVIg/plasmapheresis, treat precipitant.
Correct: B) Aminoglycosides
Concept: Drugs that worsen MG — aminoglycosides impair NMJ transmission Recall
Why B: Aminoglycosides (gentamicin) impair neuromuscular transmission and must be avoided in myasthenia. Fluoroquinolones and macrolides are also avoided. Safe: penicillins, cephalosporins, carbapenems.
Discriminator: The viva favorite: which antibiotics are safe in MG — aminoglycosides and fluoroquinolones are the dangerous ones.
| A) Penicillins | Penicillins are listed as SAFE in myasthenia |
| C) Cephalosporins | Cephalosporins are safe |
| D) Carbapenems | Carbapenems are safe |
| E) Metronidazole | Metronidazole is generally not a neuromuscular blocker of concern |
Trap: Safe-vs-unsafe trap — the source lists both; the question asks specifically for the one to avoid.
Future alert: MG: avoid aminoglycosides, fluoroquinolones, macrolides, beta-blockers, verapamil, Mg, succinylcholine.
Correct: B) Amyotrophic lateral sclerosis (MND/ALS)
Concept: MND/ALS — mixed UMN + LMN signs in the same region with no sensory loss Interpretation
Why B: Wasting and fasciculations (LMN) PLUS hyperreflexia and extensor plantars (UMN) in the same limb with normal sensation is amyotrophic lateral sclerosis — degeneration of both anterior horn cells and corticospinal tracts. Sensory sparing is characteristic.
Discriminator: Same-region mixed UMN/LMN signs + intact sensation = ALS signature.
| A) Cervical spondylotic myelopathy | Cervical myelopathy causes UMN signs with a SENSORY level and imaging showing cord compression |
| C) Multifocal motor neuropathy | MMN is pure motor with conduction block on NCS and responds to IVIg — no UMN signs |
| D) Guillain-Barré syndrome | GBS is acute, areflexic, ascending — not chronic mixed-sign wasting |
| E) Inclusion body myositis | Inclusion body myositis is myopathic with elevated CK and muscle biopsy findings |
Trap: Mixed-sign trap — the examiner puts UMN and LMN findings together to test the MND concept; no sensory loss eliminates myelopathy.
Future alert: MND: mixed UMN+LMN signs, no sensory loss, spared eye movements → riluzole 50 mg BD + supportive care.
Correct: B) Place a PEG tube early while VC is still >50%
Concept: MND nutrition — early PEG placement is safer when VC >50% Analysis
Why B: Weight loss >10% with dysphagia is the PEG indication in MND. Placing the PEG EARLY — while VC is still >50% predicted — is safer than waiting until respiratory function declines. PEG improves quality of life and may prolong survival.
Discriminator: Weight loss 12% (>10%) triggers PEG; VC 65% (>50%) is the safe window — place it now.
| A) Defer feeding tube until VC falls below 40% | Waiting until VC <40% makes the procedure riskier under respiratory compromise |
| C) Start parenteral nutrition exclusively | Parenteral nutrition is not the standard long-term enteral strategy in MND |
| D) Continue oral feeds and monitor monthly | Continued oral feeds with 12% weight loss risks aspiration and malnutrition |
| E) Insert nasogastric tube as the definitive long-term solution | NG tube is a temporary measure, not the preferred definitive option |
Trap: Timing trap — 'early while VC >50%' is the exact teaching; the stem withholds nothing, and the wrong options try to delay.
Future alert: MND PEG: weight loss >10% or aspiration risk → place early while VC >50%.
Correct: B) Prolongs survival by about 2–3 months; modest benefit
Concept: Riluzole — glutamate antagonist, modest survival benefit (2–3 months) Recall
Why B: Riluzole 50 mg BD, a glutamate antagonist, is the only generally approved disease-modifying drug for ALS. Its benefit is MODEST — it prolongs survival by roughly 2–3 months. Side effects include hepatotoxicity (monitor LFTs) and nausea.
Discriminator: 'Only approved drug' + realistic expectation = the modest survival figure, not a cure.
| A) Cure of the disease within 1 year | Riluzole is not a cure — the 2–3 month survival benefit is the honest number |
| C) Restores muscle strength in 6 months | It does not restore strength; symptomatic therapy addresses quality of life |
| D) Prevents all respiratory complications | BiPAP and cough assist address respiratory complications, not riluzole |
| E) Slows sensory loss progression | ALS has no sensory loss; that statement is nonsense on its face |
Trap: Overpromise trap — the exam tests whether you know the modest truth instead of exaggerating benefit.
Future alert: Riluzole 50 mg BD: modest survival benefit (2–3 months); monitor LFTs.
Correct: A) Pseudobulbar affect (emotional lability) — treat with amitriptyline or SSRIs; part of the UMN bulbar picture
Concept: Pseudobulbar affect in MND — emotional lability from UMN bulbar involvement Interpretation
Why A: Pathological laughing/crying (emotional lability) with spastic dysarthria and brisk jaw jerk is pseudobulbar affect — from bilateral UMN (corticobulbar) involvement. It is treated with amitriptyline 10–25 mg or SSRIs (dextromethorphan-quinidine where available).
Discriminator: Laughing/crying + brisk jaw jerk + spastic bulbar signs = pseudobulbar affect, not primary depression.
| B) Depression — start a dopamine agonist | This is not depression in the mood sense; dopamine agonists are not the treatment |
| C) Delirium — start an antipsychotic | Not delirium — consciousness is normal and onset is chronic |
| D) Wernicke encephalopathy — give thiamine | Wernicke encephalopathy is acute with ophthalmoplegia and ataxia — not this picture |
| E) Anxiety disorder — start a benzodiazepine only | Benzodiazepines alone do not address pseudobulbar affect |
Trap: Mislabel trap — the crying makes examinees default to depression; the UMN bulbar signs rebrand it as pseudobulbar affect.
Future alert: Pseudobulbar affect: amitriptyline or SSRIs; reassurance that it is a UMN sign, not a mood disorder.
This MedCORE is not a medical textbook. It is only designed for rapid, last-minute recall and should be treated like a high-yield cheat sheet, not a complete learning resource. Use it to memorize critical algorithms and recognition patterns.