Source / episode info
- **Episode:**638
- **Title:**DIP Ep 638: USMLE Step 2/3 Rapid Review Series 134
- **Published:**2026-03-05
- Source:Episode page
One-liner
This rapid review emphasizes recognizing alternate names and classic associations across multiple systems, covering GI motility disorders (Toxic Megacolon, Hirschsprung), dermatophytosis (Tinea corporis), gynecologic pathology (Asherman's syndrome), neuro-autonomic syndromes (Multiple System Atrophy), calcification patterns (Samoydes), and drug management principles (Ethacrynic acid, Sulfonylureas).
High-yield summary
- Toxic Megacolon: Strongly associated with Clostridioides difficile colitis. Also consider other causes of severe colonic dilation/ileus in the setting of opioids or bowel obstruction. Transverse colon diameter > 6 cm is highly worrisome.
- Multiple System Atrophy (MSA): A Parkinson's plus syndrome characterized by a triad: autonomic dysfunction, parkinsonism, and orthostatic hypotension. Key signs include poor sweating (anhidrosis/hypohidrosis) and significant drop in systolic BP (>20 mmHg) upon standing.
- Tinea Infections: The most common cause of Tinea corporis is Trichophyton species. For scalp or nail involvement, systemic therapy (Terbinafine or Griseofulvin) is required; topical agents are insufficient.
- Asherman's Syndrome: A cause of infertility resulting from intrauterine adhesions/synechiae, typically following multiple D&C procedures. Treatment involves hysteroscopic lysis.
- Ethacrynic Acid: Must be considered as a loop diuretic alternative when a patient has a history of severe sulfur drug allergy (e.g., to Trimethoprim-sulfamethoxazole).
- Samoydes Calcifications: Associated with four classic malignancies: Papillary thyroid cancer, Mesothelioma (risk factor: asbestos), Serocystadenocarcinoma of the ovary, and Germ cell tumors (GCT).
Learning objectives
- Identify and differentiate various types of colonic pseudo-obstruction syndromes (e.g., Toxic Megacolon vs. CD).
- Recognize the classic clinical triad and associated complications of Multiple System Atrophy (MSA).
- Differentiate between the etiologies, names, and management strategies for uterine adhesions (Asherman's syndrome) and congenital megacolon (Hirschsprung disease).
- Apply knowledge of drug allergies to select appropriate alternative medications (e.g., Ethacrynic acid for loop diuretic effect in sulfur allergy).
- Correlate specific calcification patterns with underlying malignancies (Samoydes pattern).