Pregnancy in renal transplant patients: Renal function markers and maternal-fetal outcomes.

OBJECTIVES: We aimed to evaluate laboratory markers in women who got pregnant after renal transplantation. STUDY DESIGN: Cross-sectional prospective study. MAIN OUTCOME MEASURES: Renal function parameters and maternal and fetal data were assessed in renal transplant recipients. RESULTS: Forty-three women who got pregnant after renal transplantation (mean age, 28.5 years; mean gestational age, 35.6 weeks) were included. Most patients (53.5%) received a renal transplant from a deceased donor. Podocyturia was not significantly correlated with other renal function markers. Mean period from transplantation to pregnancy was approximately 5 years; this period was not associated with obstetric complications or changes in renal markers. A gradual increase was observed in the following parameters during pregnancy and puerperium: serum creatinine levels (P < 0.001), proteinuria (P < 0.001), urinary protein/creatinine ratio (P < 0.001), and albumin/creatinine ratio (P < 0.001). The sensitivity and specificity of protein/creatinine ratio in predicting preeclampsia were high (96.0% and 94.0%, respectively). Elevated serum creatinine levels, urinary albumin/creatinine ratio, and retinol-binding protein levels in the third trimester were associated with prematurity (P < 0.001). Preeclampsia was the main cause of renal function decline at the end of pregnancy (65.0% of cases). Approximately four (9.5%) pregnant women presented with premature rupture of membranes and 18 (42.0%) with a urinary tract infection. CONCLUSIONS: Proteinuria, urinary protein/creatinine ratio, and retinol-binding protein levels were elevated in patients with preeclampsia. Using these markers to assess renal function during pregnancy may be clinically useful for detecting and monitoring renal injury in renal transplant recipients.

Race adjustment for estimating glomerular filtration rate is not always necessary.

BACKGROUND: Estimated glomerular filtration rate (eGFR) is very important in clinical practice, although it is not adequately tested in different populations. We aimed at establishing the best eGFR formulas for a Brazilian population with emphasis on the need for race correction. METHODS: We evaluated 202 individuals with chronic kidney disease (CKD) and 42 without previously known renal lesions that were additionally screened by urinalysis. Serum creatinine and plasma clearance of iohexol were measured in all cases. GFR was estimated by the Mayo Clinic, abbreviated Modification of Diet in Renal Disease (MDRD) and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formulas, and creatinine clearance was estimated by the Cockcroft-Gault (CG) formula. Plasma clearance of iohexol was used as the gold standard for GFR determination and for the development of a Brazilian formula (BreGFR). RESULTS: Measured and estimated GFR were compared in 244 individuals, 57% female, with a mean age of 41 years (range 18-82). Estimates of intraclass correlation coefficients among the plasma clearance of iohexol and eGFR formulas were all significant (p < 0.001) and corresponded to the following scores: CG 0.730; obesity-adjusted CG 0.789; Mayo Clinic 0.804; MDRD 0.848; MDRD1 (without race adjustment) 0.846; CKD-EPI 0.869; CKD-EPI1 (without race adjustment) 0.876, and BreGFR 0.844. CONCLUSIONS: All cited eGFR formulas showed a good correlation with the plasma clearance of iohexol in the healthy and diseased conditions. The formulas that best detected reduced eGFR were the BreGFR, CKD-EPI, and CKD-EPI1 formulas. Notably, the race correction included in the MDRD and CKD-EPI formulas was not necessary for this population, as it did not contribute to more accurate results.