A 34-year-old man comes to the physician because of palpitations, shortness of breath, diarrhea, and abdominal cramps for 2 months. Physical examination shows cutaneous flushing of the face. Auscultation of the chest shows bilateral wheezing. A 24-hour urine collection shows increased 5-hydroxyindoleacetic acid (5-HIA A) concentration. Abdominal imaging shows a tumor in the small intestine. Which of the following is most likely responsible for this patient's condition?

Question

A 34-year-old man comes to the physician because of palpitations, shortness of breath, diarrhea, and abdominal cramps for 2 months. Physical examination shows cutaneous flushing of the face. Auscultation of the chest shows bilateral wheezing. A 24-hour urine collection shows increased 5-hydroxyindoleacetic acid (5-HIA A) concentration. Abdominal imaging shows a tumor in the small intestine.  Which of the following is most likely responsible for this patient's condition?

Quizplus · Accepted Answer

Eductional Objective: Carcinoid tumors confined to the intestine do not cause carcinoid syndrome as their secretory products are metabolized by the liver before entering the systemic circulation.  In contrast, intestinal carcinoids that metastasize to the liver and extraintestinal (eg, bronchial) carcinoids release vasoactive substances that avoid first-pass metabolism, resulting in carcinoid syndrome (eg, flushing, diarrhea, bronchospasm).

A 34-Year-Old Man Comes to the Physician Because of Palpitations