Cystatin C and neutrophil gelatinase-associated lipocalin as markers of renal function in pediatric heart transplant recipients.

Abraham BP, Frazier EA, Morrow WR, Blaszak RT, Devarajan P, Mitsnefes M, Bryant JC, Sachdeva R. Cystatin C and neutrophil gelatinase-associated lipocalin as markers of renal function in pediatric heart transplant recipients. Pediatr Transplantation 2011: 15: 564–569. © 2011 John Wiley & Sons A/S. Abstract:  We hypothesized that use of Schwartz formula underestimates the prevalence of CKD in PHT recipients. This study determined the prevalence and risk factors for CKD in PHT using novel methods-serum cystatin C, CKiD formula, Revised Schwartz formula, s- and u-NGAL. Serum BUN, creatinine, cystatin C and s- and u-NGAL were measured after prospective enrollment. Schwartz formula GFR was compared with novel methods. CKD was defined as CKiD GFR < 90 mL/min/1.73 m2. The s- and u-NGAL were compared between those with and without CKD. Potential risk factors for CKD were analyzed. Seventy-nine patients (46 male children or boys), mean age 9.9 ± 5.8 yr formed the study cohort. The prevalence of mild and moderate CKD was 2- to 3-fold higher using novel methods compared to Schwartz formula. u-NGAL and u-NGAL/Cr were significantly higher in patients with CKD. u- and s-NGAL had negative correlation with estimates of GFR. Women were at a higher risk for CKD (odds ratio 8.7) as was longer duration since transplant (p = 0.009). In conclusion, use of novel methods of GFR estimation unmasked 2- to 3-fold increased prevalence of CKD in PHT. Women and those with longer duration since transplant are at higher risk for CKD.