A 52-year-old woman presents to the clinic complaining of abdominal pain for the past 3 months. She describes epigastric pain with a dull “gnawing and burning” quality that improves after eating. She has had success treating it with antacids but has recently noticed that they have become less effective. She denies chest pain, reflux, cough, hoarseness, hematemesis, melena, and weight loss. She endorses having diarrhea. She has a history of rheumatoid arthritis. Her medications include methotrexate and daily vitamin D.
She does not drink alcohol or smoke cigarettes. Which of the following is the most likely etiology of her condition?
B) Gastrinoma
This patient’s symptoms are most consistent with peptic ulcer disease secondary to a duodenal ulcer. Duodenal ulcers typically present with epigastric gnawing pain that improves with meals. The most common etiology is H. pylori infection (>95%), though rarely it may be due to gastrinoma. Zollinger-Ellison syndrome is characterized by gastric acid hypersecretion resulting in severe acid-related peptic disease and diarrhea. Gastrinoma is a rare cause of duodenal ulcers but must be considered in the evaluation of duodenal ulcer.
Answer choice A: Antibodies against intrinsic factor, is incorrect. Chronic autoimmune gastritis is an immune-mediated attack on intrinsic factor. Its most common presentation is pernicious anemia due to B12 deficiency.
Answer choice C: Gram negative bacillus that is catalase positive, urease positive, and oxidase negative, is incorrect. H. pylori is the most common cause of duodenal ulcers; however, it is a gram-negative rod that is positive for catalase, urease, AND oxidase, making answer C incorrect.
Answer choice D: Intestinal metaplasia, is incorrect. Intestinal metaplasia in the stomach is indicative of intestinal-type gastric carcinoma. Without weight loss and systemic symptoms and no mention of the risk factors such as H. pylori infection, nitrosamine ingestion, or type A blood, this answer is less likely.
Answer choice E: Methotrexate, is incorrect. Methotrexate can have gastrointestinal side effects such as nausea and loose stools but is not associated with peptic ulcer disease.
Key Learning Point
Duodenal ulcers typically present with epigastric gnawing pain that improves with meals and classically are painful 2-5 hours after a meal when acid is secreted in the absence of a food buffer. The most common cause is H. pylori infection though it can also be caused by NSAIDs or, more rarely, gastrinoma. Gastric ulcers typically worsen with eating and can be accompanied by postprandial belching, a sensation of epigastric fullness, early satiety, fatty food intolerance, nausea, and sometimes vomiting.
