GERD and Peptic Ulcer Disease USMLE Step 1 Practice Question
A 28-year-old man presents with a 1-year history of epigastric pain and acid regurgitation unresponsive to omeprazole 40 mg twice daily for 6 months. He denies NSAID use or H. pylori symptoms. Vital signs are stable. Upper endoscopy reveals multiple peptic ulcers in the duodenum and antrum with normal mucosa elsewhere; the esophagus is intact. Laboratory studies show fasting serum gastrin of 890 pg/mL (normal <100 pg/mL) and gastric pH of 1.2 despite PPI therapy. Which of the following tests is most likely to confirm the underlying diagnosis?
Answer choices
- AFasting serum gastrin level repeated after 1 week off omeprazole
- BHelicobacter pylori urea breath test
- CSecretin stimulation test with measurement of serum gastrin responseCorrect answer
- D24-hour ambulatory esophageal pH monitoring
- EEndoscopic ultrasound of the pancreas and peripancreatic region
- FAbdominal CT imaging with contrast
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