Marathon for USMLE STEP 1 QUESTIONS PDF
A 28-year-old man has a 2-week history of watery stools and a 2.2-kg (5.0-Ib) weight loss. He has not traveled recently or taken antibiotics. The patients father has a history of ‘inflammatory bowel disease.” Physical examination reveals hyperactive bowel sounds and diffuse, mild abdominal tenderness without guarding. Stool cultures show no growth. Which of the following would most strongly support the diagnosis of Crohns disease rather than ulcerative colitis in this patient?
A. Positive assay for antisaccharomyces cerevisiae antibody (ASCA); negative assay for perinuclear antineutrophil cytoplasmic antibody (p-ANCA)
B. Barium enema examination showing inflammation of the most distal 4 cm of ileum
C. Small bowel radiograph series showing inflammation of the most distal 4 cm of ileum
D. Colonic biopsy specimens showing mucosal and submucosal inflammation and crypt abscesses
E. The patients reporting that he stopped smoking 3 or 4 weeks ago.