Reversal of impaired counterregulatory cortisol response following diazoxide treatment in a patient with non insulinoma pancreatogenous hypoglycemia syndrome: Case report and overview of pathogenetic mechanisms.

Abstract

Non-insulinoma pancreatogenous hypoglycemia syndrome (NIPHS) is one of the rare causes of endogenous hyperinsulinism. Its diagnosis is challenging and may require selective intraarterial calcium stimulation and concomitant hepatic vein sampling (SACVS). Impaired counterregulatory hormones' production in response to hypoglycemia has been previously described in patients with diabetes, insulinoma and infancy hypoglycemia. We present a case of endogenous hyperinsulinism, secondary to NIPHS, with deficient cortisol response to hypoglycemia which resolved after diazoxide treatment. A 43-year-old woman was admitted with recurrent episodes of registered fasting and postprandial hypoglycemia. Abdominal computed tomography, magnetic resonance imaging and endoscopic ultrasonography of the pancreas failed to reveal any lesion while SACVS sampling demonstrated a 5- to 8-fold increase in insulin levels in diverse parts of the pancreas. Counterregulatory hormones' measurement revealed an attenuated cortisol response. Treatment with diazoxide resulted in disappearance of hypoglycemic episodes. Twelve months later, an insulin tolerance test was performed which revealed a normal cortisol response. This report describes the first, to our knowledge, reported case in the literature of NIPHS with deficient cortisol response to hypoglycemia which resolved after diazoxide treatment. It is important for clinicians to include NIPHS in the differential diagnosis of hypoglycemia and identify possible impairment of counterregulatory hormones' production.