Chronic kidney disease after orthotopic liver transplantation: impact of hepatitis C infection

A meta-analysis of the cumulative incidence, risk factors, and clinical outcomes associated with chronic kidney disease after liver transplantation

Chronic kidney disease (CKD) remains a relatively common complication after liver transplantation (LT), and significantly impacts overall survival. We sought to assess the cumulative incidence, risk factors and mortality associated with post-LT CKD. CKD was defined as eGFR <60 ml/min/1.73 m² as estimated by the Modified Diet in Renal Disease (MDRD) formula. Single-arm meta-analysis was done to evaluate the cumulative incidence of CKD at 1-, 3-, and 5-year timepoints post-LT. Risk factors for CKD were evaluated using hazard ratios (HR). Twenty-one studies involving 44 383 patients were included. Cumulative incidence of stage 3-5 CKD was 31.44% (CI 0.182-0.447), 36.71% (CI 0.188-0.546), and 43.52% (CI 0.296-0.574) at 1, 3, and 5 years after LT, respectively. Stage 5 CKD cumulative incidence increased from 0.274% (CI 0.001-0.005) at 1 year to 2.06% (CI 0.009-0.045) at 5 years post-LT. Age, female sex, diabetes, and peri-operative acute kidney injury (AKI) were significant risk factors for CKD. Stage 4-5 CKD was associated with a decrease in overall survival (HR 3.23, 95% CI 1.74-5.98, P < 0.01). CKD after LT is relatively common, and is associated with significantly reduced overall survival. Identification of patients at high risk of developing CKD allows physicians to prophylactically use renal-sparing immunosuppression which may be crucial in achieving desirable clinical outcomes.

The Risk of End-Stage Renal Disease Among Living Donor Liver Transplant Recipients in the United States

Since initiation of model for end-stage liver disease (MELD)-based allocation for liver transplantation, the risk of posttransplant end-stage renal disease (ESRD) has increased. Recent US data have demonstrated comparable, if not superior survival, among recipients of living donor liver transplants (LDLT) when compared to deceased donor liver transplant (DDLT) recipients. However, little is known about the incidence of ESRD post-LDLT. We analyzed linked Scientific Registry of Transplant Recipients (SRTR) and US Renal Data System (USRDS) data of first-time liver-alone transplant recipients from February 27, 2002 to March 1, 2011, and restricted the cohort to recipients with a laboratory MELD score ≤25 not on dialysis prior to transplantation, in order to evaluate the incidence of ESRD post-LDLT, and to compare the incidence among LDLT versus DDLT recipients. There were 28 707 DDLT and 1917 LDLT recipients included in the analyses. The 1-, 3- and 5-year unadjusted risk of ESRD was 1.7%, 2.9% and 3.4% in LDLT recipients, compared with 1.5%, 3.0% and 4.8% in DDLT recipients (p > 0.05), respectively. In multivariable competing risk Cox regression models, there was no association between receiving an LDLT and risk of ESRD (sub-hazard ratio: 0.99, 95% CI: 0.77-1.26, p = 0.92). In conclusion, the incidence of ESRD post-LDLT in the United States is low, and there are no significant differences among LDLT and DDLT recipients with MELD scores ≤25 at transplantation.

Chronic kidney disease after liver transplantation in human immunodeficiency virus/hepatitis C virus-coinfected recipients versus human immunodeficiency virus-infected recipients without hepatitis C virus: results from the National Institutes of Health multi-site study

Hepatitis C virus (HCV) and human immunodeficiency virus (HIV) are both associated with chronic kidney disease (CKD), a major complication after orthotopic liver transplantation (OLT). The aim of this study was to assess predictors of post-OLT CKD in HIV/HCV-coinfected recipients versus HIV-infected recipients without HCV (HIV/non-HCV recipients). Data from a National Institutes of Health study of 116 OLT recipients (35 HIV/non-HCV recipients and 81 HIV/HCV-coinfected recipients) from 2003 to 2010 (Solid Organ Transplantation in HIV: Multi-Site Study) were analyzed for the pretransplant CKD prevalence [estimated glomerular filtration rate (eGFR) < 60 mL/minute for ≥3 months] and the incidence of CKD up to 3 years posttransplant. Proportional hazards models were performed to assess predictors of posttransplant CKD. A contemporaneous cohort of HCV-monoinfected transplant recipients from the Scientific Registry of Transplant Recipients database was also analyzed. The median age at transplant was 48 years, the median serum creatinine level was 1.1 mg/dL, and the median eGFR was 77 mL/minute. Thirty-four patients were suspected to have pretransplant CKD; 20 of these patients (59%) had posttransplant CKD. Among the 82 patients without pretransplant CKD (26 HIV/non-HCV patients and 56 HIV/HCV-coinfected patients), the incidence of stage 3 CKD 3 years after OLT was 62% (55% of HIV/non-HCV patients and 65% of HIV/HCV-coinfected patients), and the incidence of stage 4/5 CKD was 8% (0% of HIV/non-HCV patients and 12% of HIV/HCV-coinfected patients). In a multivariate analysis, older age [[hazard ratio (HR) = 1.05 per year, P = 0.03] and the CD4 count (HR = 0.90 per 50 cells/μL, P = 0.01) were significant predictors of CKD. HCV coinfection was significantly associated with stage 4/5 CKD (HR = 10.8, P = 0.03) after adjustments for age. The cumulative incidence of stage 4/5 CKD was significantly higher for HIV/HCV-coinfected patients versus HIV/non-HCV transplant recipients and HCV-monoinfected transplant recipients (P = 0.001). In conclusion, CKD occurs frequently in HIV-infected transplant recipients. Predictors of posttransplant CKD include older age and a lower posttransplant CD4 count. HCV coinfection is associated with a higher incidence of stage 4/5 CKD.

Risk of end-stage renal disease among liver transplant recipients with pretransplant renal dysfunction

Guidelines recommend restricting simultaneous liver-kidney (SLK) transplant to candidates with prolonged dialysis or estimated glomerular filtration rate (eGFR) <30 mL/min/1.73m(2) for 90 days. However, few studies exist to support the latter recommendation. Using Scientific Registry of Transplant Recipients and Medicare dialysis data, we assembled a cohort of 4997 liver transplant recipients from February 27, 2002-January 1, 2008. Serial eGFRs were calculated from serum creatinines submitted with MELD reports. We categorized recipients by eGFR patterns in the 90 days pretransplant: Group 1 (eGFR always >30), Group 2 (eGFR fluctuated), Group 3 (eGFR always <30) and Group 4 (short-term dialysis). For Group 2, we characterized fluctuations in renal function using time-weighted mean eGFR. Among liver-alone recipients in Group 3, the rate of end-stage renal disease (ESRD) by 3 years was 31%, versus <10% for other groups (p < 0.001). In multivariable Cox regression, eGFR Group, diabetes (HR 2.65, p < 0.001) and black race (HR 1.83, p = 0.02) were associated with ESRD. Among liver-alone recipients in Group 2, only diabetics with time-weighted mean eGFR <30 had a substantial ESRD risk (25.6%). In summary, among liver transplant candidates not on prolonged dialysis, SLK should be considered for those whose eGFR is always <30 and diabetic candidates whose weighted mean eGFR is <30 for 90 days.

The assessment of GFR after orthotopic liver transplantation using cystatin C and creatinine-based equations

The measurement of kidney function after orthotopic liver transplantation (OLT) is still a clinical challenge. Cystatin C (CysC) has been proposed as a more accurate marker of renal function than serum creatinine (sCr). The aim of this study was to evaluate sCr- and CysC-based equations including the Chronic kidney disease (CKD)-EPI to determine renal function in liver transplant recipients. CysC and sCr were measured in 49 patients 24 months after OLT. The glomerular filtration rate (GFR) was calculated using the MDRD 4, the Cockroft-Gault, Hoek, Larsson, and the CKD-EPI equations based on sCr and/or CysC. As reference method, inulin clearance (IC) was estimated. Bias, precision, and accuracy of each equation were assessed and compared with respect to IC. Forty-five percent had a GFR < 60 ml/min/1.73 m(2) according to the IC. The Larsson, the Hoek and the CKD-EPI-CysC formula identified the highest percentage of patients with CKD correctly (88%, 88%, and 84%, respectively). The sCr-based equations showed less bias than CysC-based formulas with a similar precision. All CysC-based equations were superior as compared with sCr-based equations in the assessment of renal function in patients with an IC < 60 ml/min/1.73 m(2).