Source / episode info

• **Episode:**590
• **Title:**DIP Ep 590: 2025 USMLE Step 1 Free 120 Discussion Part 8 (Q71-80, super helpful for Step 2 and 3!)
• **Published:**2025-04-11
• Source:Episode page

One-liner

This episode provides a comprehensive review of biostatistics (ARR), portal hypertension management, medical ethics in communication and obstetrics, salivary gland pathology from eating disorders, tropical infectious diseases (Leishmaniasis), channelopathies (Hypokalemic PP), neonatal endocrinology, cardiac valve anatomy/murmurs, and common skin and soft tissue infections.

High-yield summary

• Biostatistics: Absolute Risk Reduction (ARR) is calculated as the difference between the risk in the control group and the risk in the intervention group (R_{control} - R_{intervention}).
• Portal Hypertension: In cases of refractory portal hypertension, a Transjugular Intrahepatic Portosystemic Shunt (TIPS) procedure is used to bypass the liver by connecting the portal vein to a distal systemic vein (e.g., inferior vena cava). This increases the risk of hyperammonemia and hepatic encephalopathy.
• Communication Ethics: When dealing with patient ambivalence or non-compliance (e.g., smoking cessation), use Motivational Interviewing, which involves drawing out the patient's own reasons for change rather than giving direct advice.
• Tropical Disease: Cutaneous Leishmaniasis is transmitted by the sandfly and presents as painless, non-healing ulcers that progress from papules to shallow ulcers. Treatment often involves sodium stibogluconate.
• Channelopathies: Hypokalemic Periodic Paralysis (HypoPP) is an autosomal dominant channelopathy triggered by high carbohydrate intake or vigorous exercise, causing transient hypokalemia and muscle weakness due to impaired action potential generation.

Learning objectives

• Apply biostatistical principles to calculate absolute risk reduction in clinical trials.
• Differentiate between various causes of portal hypertension and appropriate shunt procedures (TIPS).
• Utilize motivational interviewing techniques when counseling patients with chronic, difficult behaviors.
• Recognize the pathophysiology and management of salivary gland enlargement secondary to vomiting/eating disorders.
• Identify the vector and treatment for endemic tropical diseases like Cutaneous Leishmaniasis.

Board exam buzzwords