Endocrine Abstracts

Methods: Retrospective and descriptive study in a sample of 36 patients with suspected hypoglycemia who were admitted to our Service to perform a 72-hour fasting test. Demographic, clinical data and results of fasting test were analyzed. Endogenous hyperinsulinism criteria were considered to be the combination of plasma glucose <55 mg dl, insulin >3 mcrU / ml and C peptide > 0.6 ng/ml, in the absence of detection of sulfonylureas.

Results: The average age was 37 years old (81.1% women). The average weight was 66.62 kg and BMI 25.93 kg/m². They presented an average evolution of clinical syndrome of 4.6 years. 62.2% reported neuroglycopenic symptoms and 86.5% adrenergic symptoms coinciding with an average capillary blood glucose level of 49.52 mg/dl. 17% referred fasting hypoglycemia and 19.4% postprandial hypoglycemia. The average HbA1C was 5.07%. 91.7% improved their symptoms after supplements with sugar (the rest remitted spontaneously). In the initial evaluation, drug, serious illness and hormonal deficit were ruled out. The test was completed in 26.2±17.58 hours in 5 patients. Only 3 patients (8.3%) were positive for hypoglycemia due to endogenous hyperinsulinism with an average plasma glucose of 37 mg/dl, insulin 10.05 mcrU/ml and peptide C 3.35 ng/ml, subsequently confirming the diagnosis of insulinoma by imaging tests.

Conclusions: Most of patients completed the fasting test for 72 hours without clinical incidents and without hypoglycemia less than 45 mg/dl, ruling out hyperinsulinemic hypoglycaemia.

In view of these data, it could be concluded that it is important to document the Whipple triad before concluding a possible diagnosis of hypoglycemia to avoid unnecessary tests.