Pancreatic B-cell proliferation in persistent hyperinsulinemic hypoglycemia of infancy: an immunohistochemical study of 18 cases.

Persistent hyperinsulinemic hypoglycemia of infancy (PHHI) is characterized by severe hypoglycemia related to inappropriate insulin secretion. Morphologically, a tumoral and a nontumoral form are recognized. The tumoral form can be subdivided into adenomatous hyperplasia (in infants) and adenoma (in children). On the other hand, nesidioblastosis, considered until recently as a persistent B-cell replication, has repeatedly been proposed as the condition responsible for the nontumoral form of PHHI. We studied the proliferation rate of B cells in 18 patients affected by PHHI (7 nontumoral and 11 tumoral cases, including 4 adenomas and 7 adenomatous hyperplasias) and in 18 age-matched controls, using a double immunohistochemical technique detecting Ki-67, a nuclear endogenous antigen only present during cell proliferation, and insulin as pancreatic B-cell markers. Our results clearly show that "nesidioblastosis" is not related to an abnormal B-cell proliferation, because the B-cell labeling index (LI), reported as the mean plus or minus the standard error of the mean, is not statistically different between nontumoral PHHI (29.4 +/- 7.4) and age-matched controls (19.6 +/- 5.3). Furthermore, the Ki-67 positivity was not more prominent in small clusters of B cells in nesidioblastosis than in large islets. In tumoral PHHI, the LI was significantly higher in cases of focal adenomatous hyperplasia (77.6 +/- 10.9) than in either age-matched controls (19.9 +/- 6.9; P < .005) or in adenomas (27.9 +/- 13.7; P < .025); the values of this last group did not differ from those of age-matched controls (18.5 +/- 8.5). These data definitely demonstrate that nesidioblastosis does not correspond to an abnormal B-cell proliferation and that the focal forms of PHHI must be subclassified

Partial or near-total pancreatectomy for persistent neonatal hyperinsulinaemic hypoglycaemia: the pathologist's role.

AIMS: To determine whether the presence of abnormal B-cell nuclei predicts the existence of a focal or of a diffuse form of persistent neonatal and infantile hyperinsulinaemic hypoglycaemia in a series of 20 infants. METHODS AND RESULTS: Intra-operative frozen sections were performed on small specimens from the pancreatic head, isthmus and tail. In 13 cases, abnormal B-cell nuclei were identified, but even a near-total pancreatectomy was insufficient to cure some of these patients, in whom no focal lesion was detected. On the other hand, abnormal insular B-cell nuclei were not found in seven cases; based on the results of selective venous catheterization, a limited resection was performed, sufficient to cure each patient, and a focal adenomatous hyperplasia was found in each resected specimen. CONCLUSIONS: Intra-operative examination of small pancreatic specimens taken from the different parts of the gland allows one to determine the type of lesion (focal or diffuse) in neonatal onset hyperinsulinaemic hypoglycaemia, and to decide on the most appropriate surgical treatment

Long-term treatment of persistent hyperinsulinaemic hypoglycaemia of infancy with diazoxide: a retrospective review of 77 cases and analysis of efficacy-predicting criteria.

Primary persistent hyperinsulinaemic hypoglycaemia of infancy is rare. Diazoxide treatment remains the mainstay of medical therapy in long-term management. We reviewed 77 cases of primary persistent hyperinsulinism in neonates and infants who were treated with diazoxide and studied criteria predictive of therapeutic efficacy. The only criterion identified was age at manifestation. All but 1 of the 31 neonatal cases were unresponsive to diazoxide. Responsiveness increased with age: 12 of 39 early-infantile cases, and all seven late-infantile cases were diazoxide-responsive. In responders, a diazoxide dose of 10-15 mg/kg per day was always effective, suggesting an "all or none" response. Diazoxide-resistant hyperinsulinism is characterized by its severity with higher plasma insulin levels. The analysis of 46 surgically treated patients showed that the efficacy of diazoxide is not related to the aetiology of the pancreatic lesions. In six cases, after many years of management, diazoxide treatment was stopped without recurrence of hypoglycaemia. CONCLUSION: Diazoxide is an efficient treatment in the long-term management of most persistent hyperinsulinaemic hypoglycaemia of infancy revealed in infants and children but is usually ineffective in neonatal forms. Drug efficacy does not correlate with anatomical lesions. Medical treatment can sometimes be stopped after many years of management without recurrence of disease manifestations

Long-term treatment of persistent hyperinsulinaemic hypoglycaemia of infancy with diazoxide: a retrospective review of 77 cases and analysis of efficacy-predicting criteria.

Primary persistent hyperinsulinaemic hypoglycaemia of infancy is rare. Diazoxide treatment remains the mainstay of medical therapy in long-term management. We reviewed 77 cases of primary persistent hyperinsulinism in neonates and infants who were treated with diazoxide and studied criteria predictive of therapeutic efficacy. The only criterion identified was age at manifestation. All but 1 of the 31 neonatal cases were unresponsive to diazoxide. Responsiveness increased with age: 12 of 39 early-infantile cases, and all seven late-infantile cases were diazoxide-responsive. In responders, a diazoxide dose of 10-15 mg/kg per day was always effective, suggesting an "all or none" response. Diazoxide-resistant hyperinsulinism is characterized by its severity with higher plasma insulin levels. The analysis of 46 surgically treated patients showed that the efficacy of diazoxide is not related to the aetiology of the pancreatic lesions. In six cases, after many years of management, diazoxide treatment was stopped without recurrence of hypoglycaemia. CONCLUSION: Diazoxide is an efficient treatment in the long-term management of most persistent hyperinsulinaemic hypoglycaemia of infancy revealed in infants and children but is usually ineffective in neonatal forms. Drug efficacy does not correlate with anatomical lesions. Medical treatment can sometimes be stopped after many years of management without recurrence of disease manifestations