Outcome of cystic fibrosis-related diabetes two years after lung transplantation.

BACKGROUND Although transplantation is known to impair glucose tolerance, evolution of pre-existing diabetes after lung transplantation (LT) in cystic fibrosis (CF) has never been described. OBJECTIVES We aimed to assess the outcome of CF-related diabetes (CFRD) after LT, with the hypothesis that suppressing chronic inflammatory foci may improve glucose tolerance in some patients. METHODS In a retrospective study of 29 CF diabetic patients treated with insulin and undergoing LT, CFRD control was assessed 3 months before LT and 1 (n = 27) and 2 (n = 18) years after LT by measuring insulin dosage, fasting blood glucose and glycosylated hemoglobin (HbA1c) levels. Patients with HbA1c ≤7% and an insulin dose ≤1 UI/kg/day were defined as having controlled CFRD (group A). Other patients were assigned to group B. RESULTS Before LT, 19 (65.5%) patients were in group A. At 2 years, 6 of 10 (60%) patients who were in group B prior to LT had moved into group A, which then comprised 77.8% of all patients. Insulin could have been stopped in 5 patients. Uncontrolled CFRD before LT (OR = 16) and a long delay between the diagnosis of CFRD and LT (OR = 1.3) were significant predictors of uncontrolled CFRD at 1 year. CONCLUSIONS LT does not seem to worsen CFRD in some patients, suggesting that in some cases, glucose tolerance may be improved by the suppression of chronic pulmonary infection.