Uncontrolled insulin secretion from a childhood pancreatic beta-cell adenoma is not due to the functional loss of ATP-sensitive potassium channels.
We report the case of an 8-year-old child who presented with severe hyperinsulinaemic hypoglycaemia due to a pancreatic islet cell adenoma. In vivo, there was no beneficial response to the hyperglycaemia-inducing agent diazoxide and as a consequence the child underwent a subtotal pancreatectomy. In vitro studies of adenomatous beta-cells revealed no operational defects in ATP-sensitive potassium channel activity and appropriate responses to diazoxide. In comparison with patients with focal adenomatous hyperplasia, genetic analysis of the isolated adenoma showed no loss of heterozygosity for chromosome 11p15 and expression of the cyclin-dependent kinase inhibitor p57(kip2). This case illustrates that the excess insulin secretion from an infantile adenoma has an aetiology different from that observed in hyperinsulinism in infancy.
Hussain
K
K
Department of Biochemistry, Endocrinology and Metabolism, Institute of Child Health, 30 Guilford Street, London, UK.
Cosgrove
K E
KE
Shepherd
R M
RM
Chapman
J C
JC
Swift
S M
SM
Smith
V V
VV
Kassem
S A
SA
Glaser
B
B
Lindley
K J
KJ
Aynsley-Green
A
A
Dunne
M J
MJ
D007516:Adenoma, Islet Cell / Q000150:complications / Q000235:genetics / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism*; D000959:Antihypertensive Agents / Q000627:therapeutic use; D002648:Child; D002880:Chromosomes, Human, Pair 11 / Q000235:genetics; D003981:Diazoxide / Q000627:therapeutic use; D005260:Female; D006801:Humans; D006946:Hyperinsulinism / Q000209:etiology; D007003:Hypoglycemia / Q000209:etiology; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000378:metabolism*; D019656:Loss of Heterozygosity; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D020409:Molecular Motor Proteins; D010180:Pancreatectomy; D010190:Pancreatic Neoplasms / Q000150:complications / Q000235:genetics / Q000378:metabolism*; D015221:Potassium Channels / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism
D000959:Antihypertensive Agents; D007328:Insulin; C075341:KIP2 protein, S cerevisiae; D008869:Microtubule-Associated Proteins; D020409:Molecular Motor Proteins; D015221:Potassium Channels; D029701:Saccharomyces cerevisiae Proteins; D000255:Adenosine Triphosphate; D003981:Diazoxide