An Uncommon Cause of Recurrent Presyncope, Dizziness, and Tachycardia: A Case Report of Diffuse, Adult-Onset Nesidioblastosis/Non-Insulinoma Pancreatogenous Hypoglycemia Syndrome (NIPHS)

Abstract

Neurovegetative and autonomic symptoms are common presentations of various diseases, ranging from psychosomatic to severe organic disorders. A 23-year-old man presented with a history of recurrent presyncope, dizziness, and tachycardia. Repeated diagnostic work-up in various clinical settings could not identify any definite cause for approximately eight years. However, the incidental detection of postprandial and exercise-induced hypoglycemia was suggestive of an insulin-related disorder. A 72 h plasma glucose fasting test revealed endogenous hyperinsulinism. Upon imaging studies, no tumor mass potentially indicating insulinoma could be detected. 68Ga-DOTA-Exendin-4 PET/CT showed diffuse tracer enrichment throughout the whole pancreas. A subtotal pancreatectomy was performed, and the diagnosis of diffuse, adult-onset nesidioblastosis was established histopathologically. This corresponds to the clinical findings of a functional β-cell disorder, also known as non-insulinoma pancreatogenous hypoglycemia syndrome (NIPHS). After nine months, the symptoms recurred, making complete pancreatectomy necessary. Postoperative laboratory evaluation exhibited no residual endogenous C-peptide production. This case illustrates the diagnostic challenges in patients presenting with unspecific, neurovegetative and autonomic symptoms with a severe and rare underlying cause.

Non-insulinoma pancreatogenous hypoglycemia syndrome (NIPHS)/Nesidioblastosis as the underlying cause of recurrent hypoglycemia in a diabetic adult

“…These abnormal beta cells, also known as nesidioblastosis, cause excessive insulin secretion, resulting in hyperinsulinism and, eventually, hypoglycemia. 3 - 5 Nesidioblastosis can be focal or diffuse. The focal type is characterized by nodular hyperplasia of islet-like cell clusters, including ductuloinsular complexes, and hypertrophy of beta cells with giant nuclei in specific pancreatic regions.…”

“…Only four cases of nesidioblastosis in PHH with known diabetes mellitus have been described, making them even more uncommon. 3 - 5 …”