Endocrine Abstracts

A 52-year-old female patient with no previous history of interest, and with no prescribed habitual chronic treatment, was admitted to our hospital to be studied for symptomatic hypoglycemias of one month of evolution. Symptoms consisted of malaise, hunger, tremors and profuse sweating that disappeared with food ingestion. She referred hypoglycemic (up to 40 mg/dl) episodes daily, both in fasting and postprandial periods. She even suffered nocturnal episodes that woke her up. On physical examination the patient showed a good general condition, no abdominal masses were palpable, with neither acanthosis nigricans, abdominal obesity, nor lipodystrophic phenotype. Anthropometrically, she presented a waist circumference of 77 cm, a height of 154 cm, a weight of 54 kg and a BMI of 23. As for family history, one brother had been studied for postprandial hypoglycemia. On admission, blood tests showed a glycemia of 46 mg/dl with insulin 257 μIU/ml, proinsulin 5.3 pmol/l and beta-hydroxybutyrate 0.72 mg/dl. A mixed meal tolerance test was performed, showing hypoglycemia at 240 minutes of 53 mg/dl with insulin levels of 1012 μIU/ml and C-peptide of 1.62 ng/ml. Behind time, in a scheduled fasting test, no sugar levels below 45 mg/dl were evident. Research for hypoglycemic agents in urine was negative. The diagnosis of endogenous hyperinsulinism was therefore made and the study was completed with a thoracoabdominal CT scan and a somatostatin receptor scintigraphy where no focal lesions were observed. The study was completed with an echo endoscopy where two space-occupying lesions were evidenced in the pancreatic body which were punctured by FNA. In the pathological anatomy no neoplastic signs were evident. Positive anti-insulin antibodies were found (86.9% N 0-8.2). Hanging in there about previous treatments, the patient revealed a previous one month- treatment with a multivitamin that contained Lipoic Acid due to a meralgia paresthetica. HLA class II typing showed DRB1*04:03 and DRB1*15 alleles, commonly associated with Hirata disease. This is a common cause of hypoglycemia in Eastern ethnicities but extremely rare in Western populations. It is associated with drugs having a sulfhydryl group such as methimazole and lipoic acid among others. The patient was released with a diet distributed in 6 daily intakes, avoiding prolonged periods of fasting, and rich in complex carbohydrates. In addition, treatment with Diazoxide (50 mg/day) and Acarbose (75 mg/day ) was started. These drugs where progressively decreased and in three months the patient gradually improved until all hypoglycemias disappeared.