Magic Table — Medical Licensing Quick Reference

All Sections

Metabolic & Pancreatic Emergencies

Endocrine — Diabetes Mellitus

Diabetes Mellitus (Type 2) & DKA

Condition	Best Initial Investigation(s)	First-Line Treatment
Diabetes Mellitus (Type 2)	HbA1c <5.7% Non-Diabetes HbA1c 5.7–6.4% Pre-Diabetes HbA1c >6.5% Diabetes FPG ≥126 mg/dL · Random Glucose ≥200 + Sx	Lifestyle modification + Metformin
Diabetic Ketoacidosis (DKA)	Delirium, Abdominal pain, Kussmaul breathing	1. IV 0.9% NaCl infusion 2. IV Insulin 3. Potassium replacement

Hypo/Hyperthyroidism, Nodules, Hyperparathyroidism

Thyroid & Parathyroid

Thyroid Disorders

Condition	Best Initial Investigation(s)	First-Line Treatment
Hyperthyroidism (Graves')	TSH: Suppressed Free T4 / Free T3: Elevated	Carbimazole / Methimazole Alt: RAI, Surgery
Hypothyroidism	TSH: Elevated Free T4: Low	Levothyroxine
Thyroid Nodule	TSH + Thyroid Ultrasound	Benign → Observe Malignant/Suspicious → Thyroidectomy
Primary Hyperparathyroidism	Serum Calcium: High PTH: High or inappropriately normal	Parathyroidectomy (if symptomatic or meets criteria)

Hypocalcemia, Cushing's, Addison's

Adrenal & Calcium

Adrenal & Calcium Disorders

Condition	Best Initial Investigation(s)	First-Line Treatment
Hypocalcemia (Post-Thyroidectomy)	Serum Ionized Ca or Total Ca + Albumin	Acute → IV calcium gluconate Chronic → Oral Calcium + Calcitriol
Cushing's Syndrome	24-hr Urinary Free Cortisol OR Overnight Dexamethasone Suppression Test No suppression	Surgical removal of cause pituitary, adrenal, ectopic
Addison's Disease	Morning Cortisol: Low ACTH: High ACTH Stimulation Test: Blunted cortisol	Hydrocortisone + Fludrocortisone

Pheo, Prolactinoma, Acromegaly, SIADH

Pituitary & Pancreatic

Pituitary & Related Disorders

Condition	Best Initial Investigation(s)	First-Line Treatment
Pheochromocytoma	Plasma Free Metanephrines OR 24-hr Urinary Fractionated Metanephrines	Pre-op α-blockade Phenoxybenzamine / Doxazosin Definitive → Adrenalectomy
Hyperprolactinemia	Serum Prolactin Pituitary MRI (if marked elevation)	Cabergoline / Bromocriptine
Acromegaly	IGF-1: Elevated OGTT: GH fails to suppress	Transsphenoidal surgery
SIADH	Serum Osmolality: Low Urine Osmolality: High Sodium: Low	1. Fluid restriction 2. Treat underlying cause

MEN 1, MEN 2A, MEN 2B

Multiple Endocrine Neoplasias

MEN Syndromes

Condition	Key Features
MEN 1	Pituitary tumors (Prolactin or GH) Pancreatic tumors Parathyroid adenoma
MEN 2A	Parathyroid hyperplasia Pheochromocytoma Medullary thyroid carcinoma
MEN 2B	Medullary Thyroid Carcinoma Pheochromocytoma Mucosal neuromas · Marfanoid habitus

Calcium–Phosphate–PTH Differentiation

Ca²⁺ / PO₄ / PTH / ALP Patterns

Ca²⁺	PO₄	PTH	ALP	Condition
↓	↓	↑	↑	Osteomalacia
↑	↓	↑	↑	Primary Hyperparathyroidism
↓	↑	↑	↑	Secondary Hyperparathyroidism (CKD)
↑	↓	↑↑	↑	Tertiary Hyperparathyroidism
↓	↑	↑	↑	Pseudohypoparathyroidism

Classic Descriptions & Sounds

Heart Murmurs

Cardiac Murmurs

Murmur / Sound	Description
Aortic Stenosis	Crescendo–decrescendo ejection systolic, radiate to Carotid
Mitral Regurgitation	Holosystolic, radiate to Axilla
Mitral Valve Prolapse	Systolic click murmur
VSD	Holosystolic harsh
Aortic Regurgitation	Early diastolic decrescendo
Mitral Stenosis	Mid-diastolic murmur
PDA	Continuous machine-like murmur
ASD	Systolic ejection with wide fixed split S2

Heart Sounds

S3 Heart Sound

Rush of blood striking the ventricle wall

→ Dilated Cardiomyopathy

S4 Heart Sound

Atrial contractions against regurgitating blood

→ HOCM

Normal Waves & Abnormalities

JVP Waveform

Normal JVP Waves

Wave	Mechanism
a wave	Atrial contraction
x wave	Atrial relaxation
c wave	Tricuspid valve closure
x descent	Passive atrial filling
v wave	Venous filling
y wave	Atrial emptying

JVP Abnormalities

Condition	Abnormality
Atrial Fibrillation	Absent a waves
Tricuspid Regurgitation	Prominent v wave
Constrictive Pericarditis	Prominent x descent
Cardiac Tamponade	Absent y descent
3rd Degree Heart Block	Canon a wave

Side Effects to Know

Important Drugs

Drug Side Effects

Drug	Side Effect
ACEI (Captopril)	Dry cough, Angioedema
CCB (Nifedipine)	Gingival hyperplasia, Peripheral edema
Statin (Simvastatin)	Myositis, Raised CK
Procainamide	SLE-like rashes
Amiodarone	Thyroid disorder, Pulmonary fibrosis
Digoxin	Blurry yellow vision, Hyperkalemia
Fibrates	Gallstone
Spironolactone	Gynecomastia, Hyperkalemia
Nitrates	Monday disease, Impotence
Beta Blockers	Impotence

MCV / Iron / TIBC / Ferritin / Transferrin

Anemia Workup

Iron Studies Differentiation

#	Cause	MCV	Iron	TIBC	Ferritin	Transferrin
1	Iron Deficiency	Low	Low	Inc	Low	Low
2	Thalassemia	Very Low	Inc	Low	Very High	Low
3	Anemia of Chronic Disease	N/Low	Low	Low	N/High	N/Low

Classic Associations

Translocations & Cancers

Chromosomal Translocations

#	Translocation	Cancer
1	t(15;17)	AML (M3) — Acute Promyelocytic
2	t(9;22)	CML — Philadelphia chromosome
3	t(14;18)	Follicular Cell Lymphoma
4	t(8;14)	Burkitt Lymphoma
5	t(11;14)	Mantle Cell Lymphoma
6	t(11;18)	Marginal Cell Lymphoma

Warm vs Cold

Autoimmune Hemolytic Anemia

Warm AIHA

Body temperature: normal or raised
Primarily IgG
Most common
Seen in SLE, HIV, Hep C, CLL
Treatment: corticosteroids

Cold AIHA

Body temperature: typically low
Primarily IgM
Rare
Mycoplasma pneumoniae & some cancers
Avoiding cold is crucial

Mechanism of Action

Anticoagulants & Antiplatelets

Medications & MOA

Medication	Mechanism of Action
Warfarin	Inhibit synthesis of vitamin K
Heparin	Activate antithrombin III
Dabigatran (DOAC)	Inhibit directly thrombin
Fondaparinux	Inhibit factor Xa
Aspirin	Inhibit irreversibly COX-1 → ↓ TXA₂ production
Prasugrel	Block P2Y12 receptor on platelet surface → inhibit aggregation
Alteplase	Convert plasminogen → plasmin → break down fibrin
Tranexamic Acid	Bind to plasminogen → prevent conversion to plasmin
Desmopressin	Release VWF → stabilize factor VIII & platelet adhesion
Eltrombopag	Activate thrombopoietin receptor → stimulate platelet production
Imatinib	Inhibit tyrosine kinase — used in CML
Deferoxamine	Bind excess iron → excrete from body

Cadet Mnemonic

O₂–Hemoglobin Dissociation Curve

Right Shift (CADET) — Releases O₂

C — ↑ CO₂
A — Acidic pH
D — ↑ DPG (2,3-BPG)
E — Exercise
T — ↑ Temperature

Left Shift — Holds O₂

↓ CO₂
Alkaline pH
↓ DPG (2,3-BPG)
Rest
↓ Temperature

Initial vs Definitive Investigation

Acute Surgical Diagnoses

Surgical Investigations

Condition	Best Initial Investigation	Definitive Investigation
Acute Appendicitis	Ultrasound (USG)	CT Abdomen/Pelvis
Cholecystitis	RUQ Ultrasound	HIDA Scan (if USG equivocal)
Bowel Obstruction	Abdominal X-ray (AXR)	CT Abdomen/Pelvis
Perforated Viscus	Erect Chest X-ray (CXR)	CT Abdomen/Pelvis (with PO contrast)
AAA Rupture	Bedside Ultrasound (FAST)	CT Angiography (if stable)
DVT	Doppler Ultrasound	Doppler Ultrasound
Thyroid Nodule	Thyroid Ultrasound	FNA Biopsy
Blunt Abdominal Trauma	FAST Exam	CT Abdomen/Pelvis (if stable)
Head Injury	Non-contrast CT Head	Non-contrast CT Head / MRI
Renal Colic	Non-contrast CT KUB	Non-contrast CT KUB

Diagnostic Associations

Urine Casts

Casts in Urine

Cast	Associated Condition
Red cast	Malignant HTN, Glomerulonephritis
WBC cast	Pyelonephritis, Transplant rejection
Fatty cast	Nephrotic syndrome
Muddy brown cast	ATN (Acute Tubular Necrosis)
Waxy cast	End-stage renal failure

Fanconi, Bartter, Gitelman, Liddle

Tubular Disorders

Renal Tubular Syndromes

Disease	Key Features
Fanconi Syndrome	Defect in PCT · Metabolic acidosis · Rickets
Bartter Syndrome	Defect in Loop of Henle · Affects Na⁺/K⁺/2Cl⁻ · AR · Hypokalemia & Hypercalciuria
Gitelman Syndrome	Defect of NaCl in DCT · AR · Hypokalemia & Hypocalciuria
Liddle Syndrome	Gain of function — ↑ Na reabsorption in collecting tubules · AD · Hypertension & Hypokalemia

Site, MOA & Side Effects

Diuretic Classes

Diuretic Comparison

Drug Class	Site	Mechanism	Key Side Effects
Carbonic Anhydrase Inhibitors Acetazolamide	PCT	Inhibits carbonic anhydrase → ↓ HCO₃⁻, Na⁺, water reabsorption	Metabolic acidosis, Hypokalemia, Paresthesias, Nephrolithiasis, Drowsiness
Osmotic Diuretics Mannitol	PCT & Loop of Henle	↑ Osmolarity of filtrate → draws water into tubule	Electrolyte imbalance, Headache/nausea, Pulmonary edema, Confusion
Loop Diuretics Furosemide · Bumetanide · Torsemide	Thick Ascending Limb	Inhibits NKCC2 (Na⁺-K⁺-2Cl⁻ cotransporter)	Hypokalemia, Hypomagnesemia, Hypovolemia, Ototoxicity, Hyperuricemia
Thiazides HCTZ · Chlorthalidone · Indapamide	Early DCT	Inhibits NCC (Na⁺-Cl⁻ cotransporter)	Hypokalemia, Hypercalcemia, Hyperglycemia, Hyperlipidemia, Erectile dysfunction
K⁺-Sparing (Aldosterone Antagonists) Spironolactone · Eplerenone	Late DCT & Collecting Duct	Competitively blocks aldosterone → ↓ Na⁺ reabsorption, ↓ K⁺ excretion	Hyperkalemia, Metabolic acidosis, Gynecomastia (spironolactone), Menstrual irregularities
K⁺-Sparing (ENaC Blockers) Amiloride · Triamterene	Late DCT & Collecting Duct	Directly blocks ENaC → ↓ Na⁺ reabsorption, ↓ K⁺ excretion	Hyperkalemia, Metabolic acidosis, Nephrolithiasis (triamterene)

Motor, Sensory & Classic Signs

Peripheral Nerve Injuries

Upper Limb Nerves

Nerve & Site	Mechanism	Motor Deficit	Sensory Deficit	Classic Sign
Radial — Axilla	Crutch pressure	Loss of wrist, finger, thumb extension	Radial nerve distribution	Wrist Drop
Radial — Mid-shaft Humerus	Spiral groove fracture	Loss of wrist, finger, thumb extension	Dorsum of hand	Wrist Drop
Radial — Wrist	Superficial laceration	No motor loss	Anatomical snuffbox	Pure sensory loss
Median — Elbow/Forearm	Supracondylar fracture	Loss of thumb opposition, abduction, flexion	Lateral 3½ fingers (palmar) & tips	Ape Hand
Median — Wrist (Carpal Tunnel)	Compression in carpal tunnel	Thenar muscle weakness/wasting	Numbness in lateral 3½ fingers (palm spared)	Benediction Hand
Ulnar — Elbow	Medial epicondylar fracture	Loss of interossei, lumbricals (3&4), thumb adduction	Medial 1½ fingers (palmar & dorsal)	Claw Hand

Lower Limb & Shoulder Nerves

Nerve & Site	Mechanism	Motor Deficit	Sensory Deficit	Classic Sign
Axillary — Surgical Neck	Anterior shoulder dislocation	Loss of arm abduction (15–90°)	"Regimental badge" area	Flat Deltoid
Musculocutaneous — Upper Arm	Stab wound, trauma	Loss of elbow flexion	Lateral forearm	Weak flexion + weakened supination
Common Peroneal — Neck of Fibula	Fracture, tight cast	Loss of dorsiflexion, eversion, toe extension	Dorsum of foot, lateral leg	Foot Drop · Steppage Gait
Sciatic — Posterior Hip	Posterior hip dislocation, IM injection	Loss of knee flexion + all below-knee movements	Most of leg & foot	Flail Foot
Femoral — Inguinal Region	Pelvic surgery, trauma	Loss of knee extension	—	—

Clinical Outcomes

Cranial Nerve Injuries

Cranial Nerve Lesions

Cranial Nerve	Clinical Outcome of Injury
I — Olfactory	Anosmia (loss of smell)
II — Optic	Monocular blindness; Bitemporal hemianopia; Homonymous hemianopia
III — Oculomotor	Complete: "Down & Out" eye, ptosis, dilated fixed pupil Pupil-sparing: "Down & Out" + ptosis (pupil normal)
IV — Trochlear	Inability to look down when eye is adducted; Vertical diplopia; Head tilt away from lesion
VI — Abducens	Medial deviation of eye (loss of abduction); Horizontal diplopia
VII — Facial	LMN: Complete ipsilateral facial paralysis (Bell's palsy) UMN: Contralateral lower-face paralysis (forehead spared)
X — Vagus	Unilateral: Hoarseness, bovine cough, uvula deviates away from lesion Bilateral: Dysphagia, nasal regurgitation, stridor
XI — Spinal Accessory	Weak head turning away from lesion; Shoulder droop; SCM/Trapezius atrophy
XII — Hypoglossal	Tongue deviates towards lesion; Fasciculations; Atrophy

Measures of Central Tendency

Biostatistics

Statistical Measures

Measure	Definition
Arithmetic Mean (Average)	The sum of all values divided by the number of values.
Median	The middle value when all values are arranged in ascending or descending order.
Mode	The value that appears most frequently in a dataset.

Postmortem Changes

Forensic Medicine

Postmortem Changes

Change	Definition	Example
Livor Mortis (Lividity)	Settling of blood in lower, dependent parts of the body due to gravity after the heart stops pumping.	Body on back shows purplish-red discoloration on back, buttocks, legs — except pressure areas stay pale.
Algor Mortis (Body Cooling)	Gradual cooling of the body after death until it reaches the surrounding environmental temperature.	Warm body in a cool room becomes cold after several hours; cooling rate helps estimate time since death.
Rigor Mortis (Body Stiffening)	Postmortem stiffening of muscles due to depletion of ATP and buildup of calcium in muscle fibers.	Joints (jaw, neck, fingers) become stiff; stiffness disappears later as decomposition starts.

Neonatal Jaundice & Muscular Dystrophies

Pediatrics

Physiological Jaundice

Appears after 24 hours of birth
Bilirubin increase <5 mg/dL
Resolves within 10–14 days
No treatment required

Pathological Jaundice

Appears within 24 hours after birth
Bilirubin increase >5 mg/dL per day
Persists after 14 days
Needs treatment according to cause

DMD vs BMD

Duchenne vs Becker Muscular Dystrophy

Variable	DMD	BMD
Onset	3–5 years	>10 years
Mutation	Absent dystrophin gene	Partial presence of dystrophin gene
Gower's Sign	Present	Not common
Prognosis	Poor	Good

Clinical Associations

Tumor Markers

Oncology Markers

Marker	Full Name	Associated Cancer(s)
PSA	Prostate-Specific Antigen	Prostate Cancer
AFP	Alpha-Fetoprotein	HCC; Non-seminomatous Germ Cell Tumors (Yolk sac)
CA-125	Cancer Antigen 125	Ovarian Cancer (esp. serous)
CEA	Carcinoembryonic Antigen	Colorectal; also Pancreatic, Lung, Gastric, Breast
CA 19-9	Carbohydrate Antigen 19-9	Pancreatic adenocarcinoma; Cholangiocarcinoma
hCG	Human Chorionic Gonadotropin	Gestational trophoblastic disease; Testicular (non-seminomatous)
β-hCG	Beta-subunit of hCG	Testicular cancer (esp. non-seminomatous)
Calcitonin	Calcitonin	Medullary Thyroid Carcinoma
Thyroglobulin	Thyroglobulin	Differentiated thyroid cancers (Papillary, Follicular)
CA 15-3 / CA 27.29	Cancer Antigen 15-3 / 27.29	Breast Cancer
LDH	Lactate Dehydrogenase	Germ cell tumors; Lymphoma; Metastatic cancers
CgA	Chromogranin A	Neuroendocrine tumors (Carcinoid, Pancreatic NET, Pheo)

Alvarado-like Score

Appendicitis Scoring System

Scoring Criteria (Total = 10)

Category	Clinical Feature	Points
Symptoms	Migratory pain to the RIF	1
	Anorexia (loss of appetite)	1
	Nausea / Vomiting	1
Signs	Tenderness in the RIF	2
	Rebound tenderness in the RIF	1
	Elevated temperature (≥37.3°C)	1
Labs	Leukocytosis (High WBC)	2
Labs	Left shift (>75% neutrophils)	1

Action by Score

Score	Probability	Recommended Action
1–4	Low (Unlikely)	Discharge or evaluate for alternative diagnosis
5–6	Intermediate (Possible)	Admit for observation ± Ultrasound/CT
7–10	High (Probable)	Surgical consultation for likely appendectomy

Agent → Antidote Quick Reference

Antidotes

Toxicology Antidotes

Agent / Toxin	Antidote
Coumadin (Warfarin)	Vitamin K
Benzodiazepines	Flumazenil
Heparin	Protamine Sulfate
Magnesium Sulfate	Calcium Gluconate
Opiates	Naloxone
Cholinergic Medications	Atropine
Digoxin	Digibind
Acetaminophen	N-Acetylcysteine (NAC)
Iron	Deferoxamine
Anticholinergics	Physostigmine
Beta Blockers	Glucagon
Methotrexate	Leucovorin
Insulin	Glucose
Methanol	Ethanol · Fomepizole
Ethylene Glycol	Ethanol · Fomepizole
Methemoglobin	Methylene Blue
Tricyclic Antidepressants	Sodium Bicarbonate
Cyanide	Sodium Thiosulfate

Contusion vs Abrasion vs Laceration

Wound Classification

Wound Comparison

Feature	Contusion (Bruise)	Abrasion (Graze)	Laceration (Cut/Tear)
Definition	Closed wound from blunt force; damages underlying blood vessels without breaking skin	Superficial open wound; outer layers of epidermis scraped away	Deep open wound; tearing or splitting of skin & underlying soft tissues
Mechanism	Blunt trauma (bumping, hitting, squeezing)	Shearing/friction against rough surface	Blunt trauma that tears skin
Appearance	Swelling & pain; discoloration (red → blue/purple → green → yellow); skin intact	Raw, weeping surface; debris; minimal bleeding (capillary ooze)	Irregular, jagged margins; bruising/swelling; significant bleeding
Layers Involved	Subcutaneous tissue & deeper structures; skin intact	Epidermis (superficial); deeper involve upper dermis	Entire dermis and often subcutaneous tissue, muscle
Healing	Heals spontaneously; hematoma if large	High infection risk if not cleaned	High infection risk; often needs stitches; significant scarring

IBD · Hepatitis · Liver Enzymes · Pancreas

GIT & Hepatology

Ulcerative Colitis

Continuous inflammation from rectum proximally
Mucosa only · bloody diarrhea, tenesmus
Pseudopolyps; ↑ colorectal cancer risk
Associated: PSC; smoking is protective

Crohn's Disease

Discontinuous skip lesions, mouth to anus
Transmural → strictures, fistulas, abscesses
Granulomas on biopsy
Associated: smoking worsens; perianal disease

Viral Hepatitis Serology

Type	Transmission	Chronic?	Key Marker
Hepatitis A	Fecal-oral	No	Anti-HAV IgM (acute)
Hepatitis B	Blood & body fluids	Yes (5% adults; >90% infants)	HBsAg · anti-HBc IgM (window) · anti-HBs (immunity) · HBeAg (replication)
Hepatitis C	Blood (needles, transfusions)	Yes (70–85%)	Anti-HCV
Hepatitis D	Requires HBV	Yes (co/superinfection)	Anti-HDV
Hepatitis E	Fecal-oral (waterborne)	No	Anti-HEV · high mortality in pregnancy

Liver Enzyme Patterns

Pattern	AST / ALT	ALP	Typical Cause
Hepatocellular (viral)	ALT ≥ AST	Normal / Mild ↑	Acute viral hepatitis
Alcoholic liver disease	AST > ALT (≥2:1)	Normal / Mild ↑	Alcohol
Cholestasis	Normal / Mild ↑	↑↑ (with GGT)	Obstruction, stones, PBC
Ischemic hepatitis	Massive rise (>1000)	Mild ↑	Shock, hypoxia
Cirrhosis	Variable (often AST > ALT)	↑	Chronic liver disease

Cirrhosis Complications

Complication	Clue	Management
Ascites / SBP	Tense abdomen; ascitic PMN >250/µL	Paracentesis + albumin; cefotaxime
Variceal bleed	Hematemesis, melena	Octreotide + terlipressin; band ligation; TIPS if refractory
Hepatic encephalopathy	Asterixis, confusion	Lactulose + rifaximin
Hepatorenal syndrome	AKI + ascites without ATN	Terlipressin + albumin; transplant
HCC	↑ AFP or new lesion on surveillance	US + AFP every 6 months; resection/transplant

Acute Pancreatitis

Sudden epigastric pain radiating to back
Lipase >3× ULN (amylase less specific)
CT with contrast if severe / doubt
Supportive: IVF, analgesia, NG if ileus; ERCP for gallstone + cholangitis

Chronic Pancreatitis

Recurrent pain; calcifications on CT
Steatorrhea, diabetes (exocrine → endocrine)
MRCP/ERCP for duct anatomy
Pancreatic enzyme replacement + insulin; pain management

Pneumonia · PFTs · Pleural Effusion · TB

Respiratory

Community-Acquired (CAP)

Typical: S. pneumoniae, H. influenzae; atypicals: Mycoplasma, Legionella
Outpatient: amoxicillin / macrolide
Admitted: β-lactam + macrolide
Severity scores (CURB-65) guide site of care

Hospital-Acquired (HAP)

≥48 h after admission; covers MRSA + Pseudomonas
Empiric: piperacillin-tazobactam or cefepime + vancomycin/linezolid
VAP: consider on ventilator
Cultures before antibiotics whenever possible

Obstructive vs Restrictive PFTs

Parameter	Obstructive	Restrictive
FEV1 / FVC	↓ (<0.70)	Normal or ↑
TLC	Normal / ↑ (hyperinflation)	↓
RV	↑	↓
DLCO	↓ in emphysema; normal in asthma	↓ (fibrosis)
Prototype	Asthma, COPD, bronchiectasis	IPF, sarcoidosis, neuromuscular
Key history	Wheeze, smoking, reversible (asthma)	Dyspnea, dry cough, crackles

Pleural Effusion — Light's Criteria (Exudate if any)

Criterion	Exudate	Transudate
Protein (pleural/serum)	>0.5	<0.5
LDH (pleural/serum)	>0.6	<0.6
Pleural LDH	>2/3 upper limit normal	<2/3
Common causes	Infection, malignancy, PE	HF, cirrhosis, nephrotic syndrome

Primary TB

Lower / mid zones, Ghon focus
Hilar lymphadenopathy
Often asymptomatic; good host immunity
May progress to miliary if immunocompromised

Secondary TB (Reactivation)

Apical / upper lobe with cavitation
Smear positive; highly infectious
Fever, night sweats, weight loss, hemoptysis
Latent → RIPE if active

RIPE Regimen

Drug	Key Side Effect / Note
Rifampicin	Orange body fluids; CYP450 inducer; hepatotoxic
Isoniazid	Peripheral neuropathy → give pyridoxine (B6); hepatotoxic
Pyrazinamide	Hyperuricemia (gout); hepatotoxic
Ethambutol	Optic neuritis → red-green color blindness (screen vision)

Bacteria · CSF · Antibiotics · HIV

ID / Microbiology

Gram Positive vs Gram Negative

Feature	Gram (+)	Gram (−)
Cell wall	Thick peptidoglycan (retains crystal violet)	Thin peptidoglycan + outer membrane (LPS)
Classic examples	Staph aureus, Strep pyogenes, enterococci, Clostridia	E. coli, Klebsiella, Pseudomonas, Neisseria
Key toxins	Exotoxins (TSST, erythrogenic toxin)	Endotoxin (LPS) → fever, shock

Meningitis — CSF Findings

Type	Cells	Glucose	Protein
Bacterial	PMN ↑↑	↓↓	↑↑
Viral	Lymphocytes	Normal	Mild ↑
Tuberculous	Lymphocytes	↓	↑↑
Fungal (cryptococcal)	Lymphocytes	↓	↑

Antibiotic Mechanisms

Class	Mechanism
β-lactams (penicillins, cephalosporins)	Inhibit cell wall synthesis (transpeptidase / PBPs)
Vancomycin	Cell wall — binds D-Ala–D-Ala (Gram + only)
Aminoglycosides	30S ribosome → misreading of mRNA
Tetracyclines	30S ribosome → blocks tRNA binding
Macrolides	50S ribosome → blocks translocation
Clindamycin / Linezolid	50S ribosome (linezolid blocks initiation)
Fluoroquinolones	DNA gyrase / topoisomerase IV
Sulfonamides + Trimethoprim	Folate synthesis (PABA analog) — sequential block
Metronidazole	DNA damage in anaerobes (free radicals)
Polymyxins (colistin)	Disrupt outer membrane — last resort

HIV — Opportunistic Infections by CD4

CD4 Count	Infection
<500	Candidiasis (oral/vaginal), TB reactivation
<200	Pneumocystis jirovecii (PCP) → TMP-SMX prophylaxis
<100	Toxoplasma encephalitis, Cryptococcal meningitis
<50	CMV retinitis, MAC (Mycobacterium avium complex)

APGAR · Hypertensive Spectrum · Ectopic · CTG

OB / GYN

APGAR Score (at 1 & 5 minutes)

Component	0	1	2
Appearance	Blue / pale	Body pink, extremities blue	All pink
Pulse	Absent	<100/min	≥100/min
Grimace (reflex irritability)	No response	Grimace	Cry / cough
Activity (tone)	Limp	Some flexion	Active movement
Respiration	Absent	Slow, irregular	Good, crying

Hypertensive Disorders of Pregnancy

Disorder	Definition	Key Point
Gestational HTN	BP ≥140/90 after 20 weeks, no proteinuria	Monitor closely
Preeclampsia	Gestational HTN + proteinuria or end-organ dysfunction	MgSO₄ seizure prophylaxis; deliver
Severe features	BP ≥160/110, platelets <100K, renal/hepatic/neuro	Deliver once stabilized
Eclampsia	Seizures in preeclampsia	MgSO₄ first-line; delivery
HELLP	Hemolysis, Elevated Liver enzymes, Low Platelets	Severe variant — deliver

Ectopic Pregnancy

Aspect	Key Facts
Risk factors	Previous ectopic, PID, IUD, IVF, tubal surgery
Presentation	Amenorrhea + pain + bleeding; ruptured → shock
Diagnosis	TVS (empty uterus) + abnormal/plateau hCG rise
Management	Stable & small → methotrexate; rupture → salpingectomy

CTG Decelerations

Pattern	Cause	Action
Early deceleration	Head compression (benign)	Observe
Variable deceleration	Cord compression	Reposition mother; amnioinfusion if refractory
Late deceleration	Uteroplacental insufficiency	Oxygen, left lateral, delivery if persists
Category III	Fetal compromise (abnormal baseline + recurrent decels)	Expedite delivery

Hypersensitivity · Rejection · Primary Immunodeficiencies · Vaccines

Immunology

Hypersensitivity Reactions (Gell & Coombs)

Type	Mechanism	Classic Examples
I — Anaphylactic	IgE + mast cells / basophils	Anaphylaxis, allergic rhinitis, asthma, food allergy
II — Cytotoxic	IgG/IgM against cell surface	AIHA, ITP, Goodpasture, ABO transfusion reaction
III — Immune complex	IgG/IgM + antigen deposits	SLE, serum sickness, post-strep GN
IV — Delayed (T cell)	Sensitized T cells (TH1 / CTL)	Contact dermatitis, PPD, transplant rejection, granulomas

Transplant Rejection

Type	Timing	Mechanism
Hyperacute	Minutes–hours	Preformed antibodies → vascular thrombosis
Acute cellular	Days–weeks	T cells infiltrate the graft
Acute humoral	Days–weeks	Antibodies against graft endothelium
Chronic	Months–years	Fibrosis / atherosclerosis, ischemia
GVHD	Weeks	Donor T cells attack recipient (bone marrow transplant)

Primary Immunodeficiencies

Defect	Disease	Hallmark
B cells	X-linked agammaglobulinemia (Bruton)	No B cells / low Ig; infections after 6 months (maternal IgG wanes)
T cells / thymus	DiGeorge (22q11 deletion)	Absent thymus, hypocalcemia, cardiac defects
B/T (late)	CVID	Low IgG/IgA/IgM, adult onset, recurrent infections
IgA	Selective IgA deficiency	Most common; anaphylaxis to blood products
B/T (severe)	SCID	Failure to thrive, severe infections in infancy
Phagocyte	Chronic granulomatous disease	NADPH oxidase defect; catalase(+) abscesses (Staph, Aspergillus); abnormal NBT test

Live Attenuated

MMR, varicella, rotavirus, yellow fever, nasal flu (LAIV), BCG, oral polio
Contraindicated in pregnancy & severe immunosuppression
Can shed in immunocompromised household

Inactivated / Killed

Flu shot (IIV), IPV, rabies, hepatitis A & B, HPV, pneumococcal
Generally safe in pregnancy & immunocompromised
May need boosters; killed organism cannot cause disease

Arches · Pouches · Teratogens · Fetal Circulation

Embryology

Pharyngeal (Branchial) Arches

Arch	Nerve	Major Derivative
1st	CN V₃ (mandibular)	Meckel cartilage → maxilla, mandible, malleus/incus; muscles of mastication
2nd	CN VII (facial)	Reichert cartilage → stapes, styloid process; muscles of facial expression
3rd	CN IX (glossopharyngeal)	Hyoid bone (greater horn), stylopharyngeus
4th & 6th	CN X (vagus)	Laryngeal cartilages & muscles; arch 4 → aortic arch, arch 6 → ductus arteriosus

Pharyngeal Pouches

Pouch	Derivative
1st	Middle ear cavity, Eustachian tube
2nd	Palatine tonsils
3rd	Thymus + inferior parathyroids
4th	Superior parathyroids + ultimobranchial body → C cells (calcitonin)

Classic Teratogens

Teratogen	Effect
Thalidomide	Phocomelia (limb defects)
Alcohol	Fetal alcohol syndrome: microcephaly, growth restriction, facial dysmorphism, intellectual disability
Retinoic acid (isotretinoin)	CNS & cardiac defects
Warfarin	Nasal hypoplasia, stippled epiphyses
Valproate	Neural tube defects (spina bifida) → use folate
Lithium	Ebstein anomaly (atrialized right ventricle)
ACE inhibitors	Renal dysgenesis, oligohydramnios
Methotrexate	Multiple anomalies, abortion

Fetal Circulation — After Birth

Structure	Closes To
Foramen ovale	Fossa ovalis (functional at birth; anatomical ~3 months)
Ductus arteriosus	Ligamentum arteriosum (patency kept by prostaglandins; closes as PGE falls)
Ductus venosus	Ligamentum venosum
Umbilical vein	Ligamentum teres (round ligament of liver)
Umbilical arteries	Medial umbilical ligaments

Mood · Psychosis · Delirium vs Dementia · Personality · Anxiety

Psychiatry

Unipolar (MDD)

Only depressive episodes — no mania/hypomania
First-line: SSRI + psychotherapy
Core: low mood, anhedonia, sleep/appetite change, guilt, poor concentration

Bipolar Disorder

At least one manic (BD-I) or hypomanic (BD-II) episode
Depression is the common polarity
First-line: mood stabilizer (lithium/valproate); avoid antidepressant monotherapy (switch risk)

Antipsychotics — Typical vs Atypical

Feature	Typical (haloperidol)	Atypical (risperidone, olanzapine)
EPS (dystonia, akathisia, parkinsonism)	High	Low (except high-dose risperidone)
Tardive dyskinesia	High	Lower
Prolactin ↑	High (D2 blockade)	Lower
Metabolic syndrome	Low	High (olanzapine, clozapine)
NMS	Rare, all classes: fever, rigidity, ↑CK → stop + dantrolene/bromocriptine

Delirium vs Dementia

Feature	Delirium	Dementia
Onset	Acute (hours–days)	Insidious (months–years)
Course	Fluctuating	Progressive
Consciousness	Impaired / clouded	Clear (until late)
Attention	Poor	Relatively preserved
Reversible?	Yes (treat cause)	Usually not

Personality Disorder Clusters

Cluster	Theme	Disorders
A — Odd / Eccentric	Suspicious, detached	Paranoid, schizoid, schizotypal
B — Dramatic / Erratic	Emotional, impulsive	Antisocial, borderline, histrionic, narcissistic
C — Anxious / Fearful	Fear of rejection / need for control	Avoidant, dependent, obsessive-compulsive

Anxiety Disorders — Key Discriminator

Disorder	Core Feature
GAD	Chronic worry about multiple domains ≥6 months + somatic symptoms
Panic disorder	Recurrent unexpected panic attacks + fear of attacks (agoraphobia)
Social anxiety	Fear of scrutiny / negative evaluation in social situations
Specific phobia	Fear of a specific object/situation → avoidance
PTSD	Trauma + re-experiencing + hyperarousal + avoidance (>1 month)

Arthritis · Bone Tumors · Osteoporosis

Musculoskeletal

Arthritis — Rapid Differentiation

Feature	OA	RA	Gout	Septic
Onset	Gradual, age-related	Insidious	Acute overnight	Acute + ill patient
Joints	Knees, hips, DIP (Heberden)	MCP, PIP, wrists (symmetric)	1st MTP (podagra)	Single joint (knee)
AM stiffness	<30 min	>1 hour	—	—
Synovial fluid	Non-inflammatory	Inflammatory	Urate crystals (neg. birefringent)	PMN >50K; culture (+)
Key test	X-ray (joint space loss)	RF / anti-CCP	Serum uric acid (normal possible in flare)	Aspiration, Gram stain + culture
Treatment	Analgesia, exercise	DMARDs (methotrexate)	Colchicine, NSAIDs, allopurinol	IV antibiotics + urgent drainage

Bone Tumors

Tumor	Age	Site	Radiograph
Osteosarcoma	10–25	Distal femur / proximal tibia (metaphysis)	Sunburst / Codman triangle
Ewing sarcoma	5–20	Diaphysis of long bones; pelvis	Onion-skin periosteal reaction
Osteochondroma	10–30	Metaphysis (most common benign)	Exostosis with cartilage cap
Multiple myeloma	>60	Axial skeleton (skull, spine, pelvis)	Punched-out lytic lesions; M spike
Giant cell tumor	20–40	Epiphysis (distal femur, proximal tibia)	Lytic "soap bubble" (after bone maturity)

Osteoporosis

T-score	Category	Action
≥ −1.0	Normal	Reassure; calcium + vitamin D
−1.0 to −2.5	Osteopenia	Risk-stratify (FRAX); treat if high risk
≤ −2.5	Osteoporosis	Treat — bisphosphonates first-line (denosumab / teriparatide alternatives)
≤ −2.5 + fragility fracture	Severe	Treat + fall prevention; reassess adherence

Stroke Territories · Brainstem · UMN vs LMN · Tracts · Seizures

Neurology

Stroke — Vascular Territories

Artery	Syndrome
MCA	Contralateral face/arm > leg; Broca / Wernicke aphasia (dominant); gaze deviation toward lesion
ACA	Contralateral leg > arm; apathy, incontinence
PCA	Contralateral homonymous hemianopia; visual agnosia, alexia
PICA — Lateral medullary (Wallenberg)	Ipsilateral Horner + ataxia + facial pain/temp loss; contralateral body pain/temp loss
Basilar	Locked-in syndrome (pons): quadriplegia, preserved consciousness + vertical eye movements
Lacunar (small vessel)	Pure motor, pure sensory, or ataxic hemiparesis — no cortical signs

Brainstem Syndromes

Level	Syndrome	Findings
Midbrain	Weber	Ipsilateral CN III (ptosis, down-and-out) + contralateral hemiparesis
Pons	Millard-Gubler	Ipsilateral CN VI + CN VII + contralateral hemiparesis
Medulla (medial)	Medial medullary	Contralateral hemiparesis + loss of proprioception/vibration; tongue deviates toward lesion (CN XII)

UMN vs LMN

Feature	UMN	LMN
Tone	Spastic	Flaccid
Reflexes	Hyperreflexia	Hyporeflexia / areflexia
Babinski	Extensor (↑)	Flexor / absent
Atrophy	Late, disuse	Early, severe
Fasciculations	No	Yes
Example	Stroke, MS, cord compression	Root / plexus / peripheral nerve injury

Spinal Cord Tracts

Tract	Carries	Lesion Effect
Dorsal columns (DCML)	Proprioception, vibration, fine touch	Ipsilateral loss below lesion
Spinothalamic	Pain, temperature	Contralateral loss 1–2 levels below
Corticospinal	Voluntary motor	Ipsilateral UMN signs (spastic)
Brown-Séquard (hemisection)	—	Ipsilateral DCML + motor; contralateral pain/temp

Seizures — Quick Classification

Type	Hallmark
Focal aware	No loss of consciousness (e.g. focal motor, sensory)
Focal impaired awareness	Automatisms, post-ictal confusion
Absence	Brief staring, 3 Hz spike-wave, child; hyperventilation triggers; no post-ictal
Generalized tonic-clonic	Tonic → clonic, cyanosis, tongue bite, post-ictal
Myoclonic	Brief shock-like jerks; early morning (JME)
Atonic	Sudden drop attacks
Status epilepticus	>5 min or recurrent without recovery → benzodiazepine first, then fosphenytoin / levetiracetam

Glycogen Storage · Lipids · Lysosomal · Inborn Errors

Biochem / Genetics

Glycogen Storage Diseases

Type	Enzyme Defect	Hallmark
I — von Gierke	Glucose-6-phosphatase	Severe fasting hypoglycemia, hepatomegaly, lactic acidosis, doll-like facies
II — Pompe	Acid α-glucosidase (lysosomal)	Cardiomyopathy, hypotonia; infantile death
III — Cori	Debranching enzyme	Hypoglycemia (milder), hepatomegaly
V — McArdle	Muscle phosphorylase	Exercise cramps, myoglobinuria; "second wind"

Lipid Disorders (Fredrickson Highlights)

Type	Defect	Finding
IIa — Familial hypercholesterolemia	LDL receptor defect	↑↑ LDL, tendon xanthomas, premature CAD (arcus cornealis)
I (rare)	Lipoprotein lipase deficiency	Chylomicronemia → eruptive xanthomas, pancreatitis, creamy serum
IV	VLDL excess	↑ TG, metabolic syndrome association

Lysosomal Storage Diseases

Disease	Enzyme	Classic Finding
Tay-Sachs	Hexosaminidase A	Cherry-red macula, neurodegeneration, startle; Ashkenazi Jewish; no hepatosplenomegaly
Niemann-Pick	Sphingomyelinase	Cherry-red macula + hepatosplenomegaly; foamy marrow cells
Gaucher	Glucocerebrosidase	Hepatosplenomegaly, bone crises, Gaucher cells, ↓ platelets
Hurler	α-L-iduronidase	Gargoylism, corneal clouding, hepatosplenomegaly; AR

PKU & MSUD

Disease	Enzyme	Hallmark	Treatment
PKU	Phenylalanine hydroxylase	Musty odor, hypopigmentation, intellectual disability; newborn screen	Dietary phenylalanine restriction (avoid aspartame)
Maple syrup urine disease	Branched-chain α-ketoacid dehydrogenase	Maple syrup urine odor, encephalopathy, hypoglycemia	Leucine restriction; thiamine

Epidemiology Measures · Screening · Prevention · EPI

Community Medicine

Epidemiology — Core Measures

Measure	Definition
Incidence	New cases in a period ÷ population at risk — measures risk
Prevalence	All existing cases ÷ population — affected by incidence × duration
Attack rate	Cases ÷ exposed population during an outbreak (a type of incidence)
Relative risk (RR)	Risk in exposed ÷ risk in unexposed — cohort studies
Odds ratio (OR)	Exposure odds in cases ÷ controls — case-control studies (approximates RR for rare disease)
Attributable risk	Risk in exposed − risk in unexposed (excess risk due to exposure)
Number needed to treat	1 ÷ absolute risk reduction

Screening Metrics (2×2)

Metric	Formula	Intuition
Sensitivity	TP ÷ (TP + FN)	Proportion of diseased correctly detected; high = few false negatives (rule-out)
Specificity	TN ÷ (TN + FP)	Proportion of healthy correctly excluded; high = few false positives (rule-in)
PPV	TP ÷ (TP + FP)	If test positive, chance the disease is truly present — falls as prevalence falls
NPV	TN ÷ (TN + FN)	If test negative, chance the patient is truly disease-free
Accuracy	(TP + TN) ÷ total	Overall correct classification

Study Designs

Design	Direction	Strength / Use
Cross-sectional	Snapshot (prevalence)	Describes prevalence; can't establish temporality
Case-control	Backward (outcome → exposure)	Rare diseases, fast, cheap; uses OR; recall bias
Cohort	Forward (exposure → outcome)	Incidence + RR; good for common outcomes; long, costly
RCT	Intervention, randomized	Best for causation; eliminates confounding; blinding; ethical limits

Prevention Levels

Level	Target	Examples
Primary	Healthy individuals	Vaccination, hand hygiene, healthy diet, seatbelts
Secondary	Early disease	Screening — mammography, BP checks, Pap smear
Tertiary	Established disease	Rehabilitation, complication control, physiotherapy

EPI Schedule — Pakistan (simplified)

Age	Vaccines
Birth	BCG, OPV-0, Hep B-1
6 weeks	Pentavalent-1, OPV-1, IPV-1, PCV-10-1, Rotavirus-1
10 weeks	Pentavalent-2, OPV-2, IPV-2, PCV-10-2, Rotavirus-2
14 weeks	Pentavalent-3, OPV-3, IPV-3, PCV-10-3, Rotavirus-3
9 months	Measles-1 (MR-1)
15 months	Measles-2 (MR-2)
Typhoid conjugate	9 months (single dose, newer addition)

ACS · Arrhythmias · AV Blocks · Heart Failure

Cardiology

Acute Coronary Syndromes

Entity	ECG	Biomarker	Management
STEMI	ST elevation, later Q waves	Troponin ↑	Reperfusion — primary PCI (or fibrinolysis if PCI >120 min)
NSTEMI	No ST elevation (ST depression / T inversion)	Troponin ↑	Antithrombotic + early invasive strategy for high risk
Unstable angina	No ST elevation	Troponin normal	Same pathway as NSTEMI (medical first)
All ACS	—	—	MONA + antiplatelets (aspirin + P2Y12), anticoagulant, statin, beta-blocker

Arrhythmias — ECG Recognition

Rhythm	Feature	Treatment
Atrial fibrillation	Irregularly irregular, no P waves, narrow QRS	Rate/rhythm control + anticoagulation (CHA₂DS₂-VASc)
Atrial flutter	Sawtooth flutter waves (250–350/min)	Rate control; ablation is curative
PSVT / SVT	Regular narrow complex, no visible P, sudden onset	Vagal maneuvers → adenosine → CCB
VT	Wide QRS, monomorphic, no capture/fusion beats	Amiodarone; cardioversion if unstable
VF	Chaotic, no cardiac output (arrest)	Defibrillation + CPR (ACLS)
Torsades de pointes	Polymorphic VT, long QT	MgSO₄; correct QT causes

AV Blocks

Degree	ECG Finding	Management
1st degree	PR >200 ms, all conducted	Observe (usually benign)
2nd — Mobitz I (Wenckebach)	PR progressively lengthens → dropped beat	Observe (AV nodal — often reversible)
2nd — Mobitz II	Sudden dropped beats, constant PR	Pacemaker (infranodal — may progress)
3rd degree (complete)	P waves and QRS dissociated	Pacemaker (emergency if symptomatic)

Heart Failure — NYHA + GDMT

NYHA Class	Limitation (ordinary activity)
I	None — no symptoms with normal activity
II	Slight — comfortable at rest, symptoms with ordinary exertion
III	Marked — comfortable at rest, symptoms with minimal exertion
IV	Severe — symptoms at rest

Drug (HFrEF)	Mortality Benefit
ARNI (sacubitril/valsartan) or ACE-I/ARB	Yes — cornerstone neurohormonal blockade
Beta-blocker (carvedilol, bisoprolol, metoprolol XL)	Yes — start after euvolaemia
MRA (spironolactone / eplerenone)	Yes — watch K⁺ and renal function
SGLT2 inhibitor (empagliflozin, dapagliflozin)	Yes — regardless of diabetes
Digoxin / diuretics	Symptom benefit only — no mortality benefit

ABG · Anion Gap · MUDPILES · Sodium / Potassium

Acid-Base

ABG — First Pass Interpretation

pH	pCO₂	HCO₃	Diagnosis
Low	High	Normal	Respiratory acidosis (hypoventilation)
Low	Normal	Low	Metabolic acidosis (anion gap?)
High	Low	Normal	Respiratory alkalosis (hyperventilation)
High	Normal	High	Metabolic alkalosis (vomiting, diuretics)
Normal	Abnormal	Abnormal	Mixed disorder — check compensation & delta gap

Anion Gap & MUDPILES

Mnemonic	Cause
M	Methanol (osmolal gap)
U	Uremia (renal failure)
D	Diabetic ketoacidosis
P	Propylene glycol
I	Isoniazid / Iron
L	Lactate (sepsis, ischemia)
E	Ethylene glycol (oxalate crystals)
S	Salicylates (also resp. alkalosis)

Anion gap = Na⁺ − (Cl⁻ + HCO₃⁻), normal ≈ 8–12. Winter's formula: expected pCO₂ = 1.5 × HCO₃ + 8 ± 2. Delta gap: ΔAG ÷ ΔHCO₃ — >1 suggests concurrent metabolic alkalosis, <1 a non-gap acidosis.

Sodium Disorders

Disorder	Causes	Correction Rule
HypoNa⁺ (dilutional)	SIADH, heart/liver/renal failure, polydipsia	Fluid restrict; do not correct >8–10 mEq/L per 24h (osmotic demyelination)
HypoNa⁺ (depletional)	Diuretics, vomiting, diarrhea, adrenal insufficiency	Normal saline; replace slowly
HyperNa⁺	Water loss (diabetes insipidus), hypertonic saline	Free-water replacement; correct slowly

Potassium Disorders

Disorder	Causes	ECG / Treatment
HyperK⁺	Renal failure, ACE-I/ARB, K⁺-sparing diuretics, hemolysis, acidosis	Peaked T waves → wide QRS; Ca²⁺ gluconate (membrane), insulin + glucose, kayexalate, dialysis
HypoK⁺	Diuretics, vomiting, diarrhea, aldosterone excess, insulin	U waves, flat T, arrhythmia; oral/IV replacement (never rapid IV bolus)