A 45-Year-Old Woman Complains of Episodic Epigastric Pain

A 45-year-old woman complains of episodic epigastric pain. She denies fevers, chills, diaphoresis, flushing, chest pain or shortness of breath. An upper endoscopy reveals severe and atypical peptic ulcer disease. Biopsy results are Helicobacter pylori negative and she denies taking NSAIDs. Continued workup should include serum levels of which of the following?

A) Serotonin
B) Gastrin
C) Vasoactive intestinal peptide (VIP)
D) Cholecystokinin (CCK)
E) Histamine