A Case of Insulinoma with Improved Reactive Hypoglycaemia after Operation OD04-OD06
Dr. Hodaka Yamada,
Jichi Medical University Saitama Medical Center, 1-847 Amanuma-Cho, Omiya-Ku, 330-8503, Saitama, Japan.
It is well known that fasting hypoglycaemia is common in insulinoma, but postprandial hypoglycaemia has also been reported. In almost all cases, the serum Immunoreactive Insulin (IRI) level is not suppressed. A 54-year-old Japanese woman experienced repeated temporary loss of consciousness simultaneously with hypoglycaemia. 5-hour on admission, she had repeated hypoglycaemia without suppression of insulin. A 5-hour Oral 75 gm Glucose Tolerance Test (5-hour OGTT) showed reactive hypoglycaemia. Her serum IRI level was suppressed. Enhanced pancreatic Magnetic Resonance Imaging (MRI) revealed a 10 mm sized tumour in the pancreas; we thus diagnosed her with insulinoma. A laparoscopic distal pancreatectomy was performed. The 5-hour OGTT was performed again post operatively. Her abnormal glucose tolerance remained, but her reactive hypoglycaemia improved. We conclude that reactive hypoglycaemia may occur in cases of insulinoma, and may be eliminated through operation. This case report has two important points. Firstly, the patient’s reactive hypoglycaemia was demonstrated. Secondly, her improving reactive hypoglycaemic state was recorded in detail.