WBR0446

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Author [[PageAuthor::Rim Halaby, M.D. [1] (Reviewed by Will Gibson) (Reviewed by Alison Leibowitz)]]
Exam Type ExamType::USMLE Step 1
Main Category MainCategory::Pathology
Sub Category SubCategory::Endocrine
Prompt [[Prompt::A 45-year-old female presents to the physician’s office with complaints of severe diarrhea of several days duration. The patient’s medical history is significant for recurrent kidney stones and a parathyroidectomy 8 years ago. Her fasting gastrin level is elevated and endoscopy reveals multiple ulcers in the stomach, duodenum, and jejunum. Which of the following findings is most frequently associated with this patient's condition?]]
Answer A AnswerA::Oral ganglioneuroma
Answer A Explanation AnswerAExp::Oral ganglioneuromatosis frequently occurs in patients with MEN2B syndrome.
Answer B AnswerB::Pheochromocytoma
Answer B Explanation AnswerBExp::Pheochromocytoma frequently occurs in MEN 2A and MEN 2B syndromes.
Answer C AnswerC::Medullary thyroid cancer
Answer C Explanation AnswerCExp::Medullary thyroid cancer frequently occurs in MEN 2A and MEN 2B syndromes.
Answer D AnswerD::Prolactinoma
Answer D Explanation AnswerDExp::Prolactinoma, a pituitary tumor, frequently occurs in MEN I syndrome.
Answer E AnswerE::Carcinoid tumor
Answer E Explanation AnswerEExp::Carcinoid tumor is an endocrine tumor, but is not frequently associated with MEN syndrome.
Right Answer RightAnswer::D
Explanation [[Explanation::The patient in this vignette most likely has Multiple Endocrine Neoplasia Type I (MEN 1). We know from the patient's past medical history that she likely had a parathyroid adenoma. Parathyroid adenomas can secrete PTH and thereby increase serum calcium and decrease serum potassium. Increased serum calcium can be lead to elevated calcium passing into the urine, thereby increasing the risk of calcium oxalate kidney stones. The definitive treatment of these tumors is surgical removal (parathyroidectomy) as in this patient.

The patient now presents with symptoms highly consistent with a gastrinoma. These are gastrin-secreting tumors that form in either the pancreas or the duodenum. Recall that gastrin is a peptide hormone that stimulated parietal cells to increase secretion of gastric acid. Patients with gastrinomas therefore frequently develop multiple ulcers due to excessive gastric acid production in the stomach. Nearly 25% of gastrinoma patients have MEN 1. A patient with who has developed both parathyroid adenoma and gastrinoma is certainly affected by MEN 1.

MEN I syndrome is characterized by parathyroid tumors, pituitary tumors, which are usually prolactinoma or GH secreting tumors, and pancreatic endocrine tumors, such as gastrinoma, insulinoma, VIPoma, or glucagonoma.
Educational Objective: MEN I syndrome often manifests with pituitary tumors, parathyroid tumors, or pancreatic endocrine tumors.
References: First Aid 2014 page 329]]

Approved Approved::Yes
Keyword WBRKeyword::Prolactinoma, WBRKeyword::pheochromocytoma, WBRKeyword::gastrinoma, WBRKeyword::neoplasia, WBRKeyword::MEN I, WBRKeyword::Wermer syndrome, WBRKeyword::diarrhea, WBRKeyword::ulcers
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