My seven year old granddaughter, who had cystic fibrosis diagnosed as an infant, was recently diagnosed with diabetes. Is diabetes a complication of or a spin off from the cystic fibrosis?

Diabetes is an uncommon but well recognised feature of late cystic fibrosis. The loss of beta cell function though does not appear to be a direct consequence of any of the many variants of the abnormal CFRT gene on the long arm of chromosome 7. Rather it seems to be a part of the generalised destruction of the exocrine part of the pancreas and is perhaps particularly related to the loss of pancreatic ducts from which new islet tissue is derived. Antibody tests are negative. In any case, I think you could say that the diabetes is a ‘complication’ rather than a ‘spin off’ from the CF.

DOB

[Editor’s comment: See Solomon MP, Wilson DC, Corey M, Kalnins D, Zielenski J, Tsui LC, Pencharz P, Durie P, Sweezey NB. Glucose intolerance in children with cystic fibrosis J Pediatr 2003 Feb;142(2):128-132.

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