A Case of Insulinoma in Pregnancy

Abstract

A 39-year-old woman in her 15th week of pregnancy presented with consciousness disturbance. She was diagnosed with hypoglycemia due to hyperemesis and recovered after glucose administration. She did not develop hypoglycemic symptoms during the remainder of the pregnancy. She gave birth at 38 weeks. Two days after delivery, she lost consciousness again with severe hypoglycemia. Insulinoma was suspected because a fasting test was positive. However, the tumor could not be identified using dynamic CT, MRI, and endoscopic ultrasonography (EUS). Based on the findings of a selective arterial secretagogue injection test, insulinoma of the proximal pancreatic tail was diagnosed using EUS-guided fine-needle aspiration. Spleen-preserving pancreatic tail resection was performed at laparotomy. Insulinoma in pregnancy often develops in the first trimester. Hypoglycemic symptoms become latent due to increased insulin resistance at an advanced gestational age, but they recur as insulin resistance improves after delivery. Insulinoma is rare during pregnancy and is difficult to diagnose, but it should be considered in pregnant women with severe hypoglycemia.