Abstract 1673: Chronic Kidney Disease in Long Term (> 5 years) Pediatric Heart Transplant Recipients
Background: Renal dysfunction has been recognized as an important morbidity in pediatric heart transplant recipients. However risk factors for chronic kidney disease in long-term (> 5 years) survivors are not well defined as are the effects of late withdrawl of calcineurin inhibitors.
Methods: We calculated glomerular filtration rates (GFR) using the Schwartz formula in long-term (> 5 years) pediatric heart transplant survivors (N=70 patients: 38 transplanted <1 year of age, 32 at > 1 year of age). Chronic kidney disease (CKD) was defined as Stage 3 National Kidney Foundation CKD (GFR<60 ml/min/1.73 m2). Logistic regression was used to analyze potential predictors of CKD and univariate and multivariate analysis were used to find independent risk factors.
Results: Actuarial freedom (SEM) from CKD at 5, 10 and 15 years after transplant was 0.957 (0.02), 0.75 (0.063) and 0.649 (0.086) respectively. . Univariate analysis revealed age <1 year at transplantation (p=0.02), hypoplastic left heart syndrome (p=0.01), GFR before transplantation (p=0.05), primary graft failure requiring mechanical support (p=0.02), lowest postoperative period GFR (p=0.03), episodes of acute renal failure after transplantation (p=0.02) and presence of other kidney disease (p=0.01) to be signifianctly associated with CKD. Multivariate analysis identified the following independant risk factors for the development of CKD: GFR before transplantation (odds ratio OR=0.86, p<0.0001), worst GFR after transplantation (OR=0.8, p<0.0001) and GFR 3 years after transplantation (OR=0.61, p=0.003). Sex, gender, mechanical support before transplant, graft ischemic time, length of inotropic support after transplant, rejection history, infection history, and medically treated systemic hypertension had no significant association. Eight patients were transitioned from calcineurin-inhibitors to sirolimus after developing Stage 3 CKD. Only 1/8 improved from stage 3 to stage 2 CKD with 3 patients ultimately undergoing kidney transplantation.
Conclusions: CKD is a frequent, progressive long term complication in pediatric heart transplant recipients which is related to GFR prior to and early after transplant and appears to be unaffected by late withdrawl of calcineurin inhibitors.