Nesidioblastosis in Patients With Severe Postbariatric Hypoglycemia: A Monocentric Case Series.

Purpose: Partial pancreatectomy has been explored as a treatment for postbariatric hypoglycemia (PBH) yet is often ineffective due to recurring hypoglycemia. Thus, the role of nesidioblastosis in PBH's pathophysiology is controversial. Complicating matters, nesidioblastosis may be present but difficult to identify on histopathology. We aim to present data and review the literature to understand the role of nesidioblastosis in PBH and assess the efficacy of pancreatic surgery for PBH treatment. Methods: Between 2010 and 2024, 7 patients with severe PBH underwent selective arterial calcium stimulation tests (SACSTs) to assess for nesidioblastosis. Subsequently, 5 of these patients underwent pancreatic surgery. Histopathological findings were reviewed. Patient characteristics and outcomes were reported. A literature review was also performed. Results: All 7 patients (100%) had SACST results consistent with nesidioblastosis. Four patients pursued partial pancreatectomy, and 1 pursued total pancreatectomy. Pancreatic histopathology showed nesidioblastosis in 2 of the 5 surgical cases. Hypoglycemia initially resolved in 3 of the 4 patients who underwent partial pancreatectomy but later recurred after 1 year in 1 patient and after 7 years in the other 2. One patient had minimal improvement leading to completion pancreatectomy. This patient and the patient who opted for initial total pancreatectomy experienced hypoglycemia resolution but developed insulin-dependent diabetes. Conclusion: Nesidioblastosis may play a role in the pathophysiology of PBH, as suggested by the SACST findings and temporary hypoglycemia resolution after surgery. However, hypoglycemia recurrence suggests other pathological mechanisms primarily contribute to PBH. Overall, our results show long-term inefficacy of partial pancreatectomy as a treatment for PBH.