Gastric Acid Secretion and Regulation

A 52-year-old man from Delhi presents with a 6-month history of epigastric pain, heartburn, and nausea. Upper endoscopy reveals a 2 cm ulcer in the gastric antrum with surrounding erythema. Rapid urease test is positive. He denies NSAID use. His serum gastrin level is 85 pg/mL (normal <100). What is the most appropriate next step in management?

A 52-year-old man from Delhi presents with chronic epigastric pain and heartburn for 8 months. Upper endoscopy reveals multiple gastric ulcers with prominent gastric folds. Serum gastrin level is 850 pg/mL (normal <100). Which investigation is most appropriate to confirm the diagnosis of Zollinger-Ellison syndrome?

A 52-year-old man from Delhi presents with a 6-month history of epigastric pain, heartburn, and nausea. Upper endoscopy reveals a 2 cm ulcer in the gastric antrum with surrounding erythema. Serum gastrin level is 850 pg/mL (normal <100). Gastric pH is 1.2. On further investigation, a 1.5 cm neuroendocrine tumor is found in the pancreatic head on CT imaging. Which of the following best explains the mechanism of acid hypersecretion in this patient?

A 52-year-old man from Delhi presents with chronic epigastric pain, bloating, and reduced appetite for 6 months. Upper endoscopy reveals multiple gastric ulcers with surrounding erythema. Histology shows loss of parietal cells and extensive intestinal metaplasia. Which of the following is the most common cause of this histological pattern?

Regarding the regulation of gastric acid secretion, all of the following statements are correct EXCEPT: