A 38-year-old woman presents with her third upper GI bleed secondary to duodenal ulcers in 3 years. Biopsies have been negative for Helicobacter pylori. She complains of diarrhea and an unintentional 5-lb weight loss. What test next?
A 38-year-old woman presents with hematemesis. Upper endoscopy reveals a duodenal ulcer with an actively spurting vessel. Hemostasis is achieved with injection of epinephrine followed by thermal coagulation. She also has several other non-bleeding shallow ulcers in other portions of the duodenum. Biopsies are negative for Helicobacter pylori. This has been her third presentation of an upper GI bleed secondary to duodenal ulcers in the past 2 years. On review of systems, she complains of intermittent diarrhea and has unintentionally lost 5 lb over the past month. Which of the following should be ordered next?
A. Serum glucagon
B. Serum prolactin
C. Serum gastrin
D. 24-hour urinary 5HIAA