Diabetic ketoacidosis in cystic fibrosis

A. B. Atlas, D. N. Finegold, D. Becker, M. Trucco and G. Kurland
Department of Pediatrics, Children's Hospital of Pittsburgh, Pa.

OBJECTIVE--To differentiate the insulin-dependent glucose intolerance associated with cystic fibrosis from type I diabetes mellitus in patients with cystic fibrosis. DESIGN--Patient report. SETTING--Tertiary care referral center. PARTICIPANT--An 11-year-old boy with cystic fibrosis who developed diabetic ketoacidosis. MEASUREMENT/MAIN RESULT--Biochemical, immunologic, and molecular techniques were used to support the sporadic association of type I diabetes mellitus in a patient with cystic fibrosis. Cystic fibrosis was confirmed by sweat test and further supported by the demonstration of a heterozygous deletion of the F508 locus. Evidence for the diagnosis of type I diabetes mellitus was developed from the clinical presentation of diabetic ketoacidosis with hyperglycemia, ketonemia, and ketonuria. Immunologic evidence included the demonstration of anti-insulin antibodies. The demonstration of homozygous absence of aspartic acid at position 57 of the HLA DQ-beta chain placed this child at high risk of type I diabetes mellitus. CONCLUSION--The clinical presentation and the presence of immunologic and genetic markers characteristic of type I diabetes mellitus supports the concordance of cystic fibrosis and type I diabetes mellitus in this patient.