Insulinoma-related Endogenous Hypoglycaemia with a Negative Fasting Test: A Case Report and Literature Review

Abstract

We present the case of a patient with a history of symptomatic hypoglycaemic episodes and a negative 72-hour fasting test with histological confirmation of insulinoma. A literature review of hyperinsulinaemic hypoglycaemia with a negative fasting test was performed. LEARNING POINTS • The 72-hour fasting test is the gold standard for insulinoma diagnosis. • Few cases of insulinoma with a negative fasting test have been reported. • New strategies for insulinoma diagnosis are being investigated.