New-onset diabetes mellitus in pediatric thoracic organ recipients receiving tacrolimus-based immunosuppression.

BACKGROUND

Tacrolimus has a negative effect on the pancreatic beta islet cell, and both glucose intolerance and diabetes mellitus are well-recognized complications of tacrolimus-based immunosuppression among adult solid organ transplant recipients.

METHODS

To determine the association between tacrolimus and new-onset diabetes mellitus in childhood, we reviewed data on 78 pediatric heart and heart-lung/lung recipients receiving tacrolimus-based immunosuppression. Trough tacrolimus levels, fasting and random blood glucose levels, and corticosteroid requirements were reviewed. Diabetes was defined as glucose intolerance requiring long-term insulin treatment more than 30 days after transplantation.

RESULTS

No patient had diabetes before introduction of tacrolimus. In heart-lung/lung recipients, 12 of 28 (43%) had development of diabetes at a median follow-up of 7 months (range 1 to 39). In this group diabetes developed in three of eight (38%) patients with cystic fibrosis and nine of 20 (45%) without (p = NS). In contrast, only two of 50 (4%) heart transplant recipients had development of diabetes. Of the 14 patients with diabetes, 10 had development of diabetes during augmentation of immunosuppression with pulsed corticosteroids. Tacrolimus trough levels were significantly lower in heart compared with heart-lung/lung transplant recipients (9.4 +/- 3.3 versus 15.3 +/- 0.9 ng/ml) (p < 0.01), and at latest follow-up significantly fewer heart transplant recipients were treated with maintenance corticosteroids (28% versus 75%; p < 0.01). In the heart-lung/lung group, no significant difference in tacrolimus levels was found between patients with and without diabetes, nor was there a significant difference in the average corticosteroid dose or number of pulses of corticosteroids per patient.

CONCLUSIONS

New-onset diabetes mellitus is rare in pediatric heart transplant recipients receiving tacrolimus-based immunosuppression, but it occurs with a high incidence after pediatric heart-lung/lung transplantation and usually develops during pulsed corticosteroid therapy. However, it is currently not possible to predict which heart-lung/ lung transplant recipients will have development of this serious complication.