Multidisciplinary approach to the focal form of congenital hyperinsulinism leads to successful treatment by partial pancreatectomy

Background/Purpose: Congenital hyperinsulinism (HI) causes severe hypoglycemia in neonates and infants. Recessive mutations of the beta-cell K-ATP channel genes cause diffuse HI, whereas loss of heterozygosity together with inheritance of a paternal mutation cause focal adenomatous HI. Although these 2 forms of HI are clinically identical, focal HI can be cured surgically. The authors reviewed their experience with partial pancreatectomy for focal HI. Methods: From December 1998 to January 2003, 38 patients (ages 2 weeks to 14 months; median age, 10 weeks) were treated with partial pancreatectomy for focal HI. Before surgery, patients had localization studies using selective arterial calcium stimulation with venous sampling or transhepatic portal venous sampling. At operation, the focal lesion was found using the preoperative localization data and multiple pancreatic biopsies with frozen section analysis, followed by partial pancreatectomy. A complete response at follow-up was defined as no requirement for glycemic medications, no continuous tube feedings, and no diabetes mellitus. Results: Nineteen pancreatic focal lesions were in the head; 15 were in the neck, body, or tail; and 4 had more extensive involvement. Lesions that required substantial resection of the pancreatic head underwent Roux-en-Y pancreaticojejunostomy to preserve the normal body and tail. Lesions of the body or tail were usually treated with partial distal pancreatectomy. Ninety-two percent (35 of 38) of patients had a complete response to surgery. Three patients have required glycemic medications. No patient is diabetic. Surgical complications included additional resection for residual disease (3), small bowel obstruction requiring laparotomy and enterolysis (2), and chylous ascites (3) that resolved with medical management. Conclusions: A multidisciplinary approach to patients with the focal form of congenital hyperinsulinism can distinguish focal from diffuse disease, localize focal lesions, and permit partial pancreatectomy with cure in most patients.