Gastrointestinal, Physiology, USMLE Step 1 - Full Vignette with Extended Explanations

Описание: Chapters
00:00 - Case Presentation and Question
03:27 - Correct Answer Revealed and Explanation

An 81-year-old man presents with chronic loose stools, urgency, and episodes of incontinence, which worsen with stress and certain meals and improve during fasting. His history includes multiple comorbidities and previous surgeries, with normal recent testing for common etiologies. What clinical considerations and risk factors should you evaluate when selecting treatment options for persistent diarrhea in complex older adults?

VIDEO INFO
Category: Gastrointestinal, Physiology, USMLE Step 1
Difficulty: Expert - Expert level - For those seeking deep understanding
Question Type: Contraindications
Case Type: Rare Presentation

Watch the video for explanation, or see the full explanation at: https://endlessmedical.academy/auth?h...

QUESTION
An 81-year-old retired man living with his spouse presents for evaluation of long-standing loose, nonbloody stools three to five times daily with urgency and occasional incontinence, worse with stress and restaurant meals and improved during fasting. He denies weight loss, nocturnal pain, fevers, or recent antibiotics....

OPTIONS
A. Eluxadoline 75 mg orally twice daily with food in a post-cholecystectomy patient without a gallbladder
B. Rifaximin 550 mg orally three times daily for 14 days for diarrhea-predominant irritable bowel syndrome
C. Loperamide up to a prescription maximum of 16 mg in 24 hours as needed for watery stools when afebrile
D. Alosetron 0.5 mg orally twice daily with careful monitoring for constipation and ischemic colitis


Further reading:

[1] Pharmacological management of irritable bowel syndrome with diarrhea (IBS-D)
Authors: American Gastroenterological Association
American Gastroenterological Association. Year: 2022. Type: Guideline.
Educational value: Outlines indications, efficacy, and safety of IBS-D therapies.
Confidence of existence and relevancy: 100%
Available at: https://gastro.org/clinical-guidance/...

[2] FDA Drug Safety Communication: Increased risk of serious pancreatitis with eluxadoline in patients without a gallbladder
Authors: U.S. Food and Drug Administration
U.S. Food and Drug Administration. Year: 2017. Type: Source.
Educational value: Emphasizes safety and contraindications in IBS-D pharmacotherapy selection.
Confidence of existence and relevancy: 100%
Available at: https://www.fda.gov/drugs/drug-safety...

Links to sources are provided for optional further reading only. The questions and explanations are independently authored and do not reproduce or adapt any specific third-party text or content.

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