Source / episode info
- **Episode:**202
- **Title:**Divine Intervention Episode 202 – USMLE Step 2CK Rapid Review Series 30.
- **Published:**2020-01-11
- Source:Episode page
One-liner
This episode reviews key differential diagnoses including Zika/Toxoplasmosis/CMV; pure motor strokes due to internal capsule pathology; transfusion reactions (AHTR, TRALI, TACO); genetic disorders like Fragile X and Myotonic Dystrophy; and toxicology management for methanol, cyanide, and iron poisoning.
High-yield summary
- Zika Virus: Associated with microcephaly, thin cerebral cortex, seizures, and foreign travel history. Calcifications are diffuse.
- Congenital Infections Triad: Toxoplasmosis classically presents with intracranial calcifications and hydrocephalus; CMV with periventricular calcifications and a "blueberry muffin" rash; Syphilis with snuffles/rhinitis.
- Pure Motor Stroke: Suggests pathology at the posterior limb of the internal capsule (subcortical), often due to vasculitis or rupture of lenticulostriate arteries, with hypertension being the primary risk factor.
- Transfusion Complications: Distinguish between TRALI (non-cardiogenic pulmonary edema; normal PCWP) and TACO (cardiogenic pulmonary edema; elevated PCWP/CVP). AHTR is a Type II hypersensitivity reaction.
- Toxicology Management: Methanol poisoning requires N-acetylcysteine (NAC) to replenish glutathione; Cyanide poisoning requires inducing methemoglobinemia with Amyl nitrite followed by Sodium thiosulfate.
Learning objectives
- Differentiate the clinical and radiological findings of congenital infections (Zika, CMV, Toxoplasmosis).
- Identify the anatomical location responsible for pure motor or pure sensory strokes (posterior limb of internal capsule).
- Apply knowledge of transfusion complications, specifically differentiating TRALI from TACO.
- Recall the specific antidotes and mechanisms for methanol, cyanide, and iron poisoning.
- Differentiate between autosomal dominant, recessive, X-linked, and mitochondrial inheritance patterns in genetic disorders.
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