HCV cirrhotic patients treated with direct-acting antivirals: Detection of tubular dysfunction and resolution after viral clearance.

BACKGROUND/AIMS: Hepatitis C virus (HCV) has been identified in tubular epithelial cells of infected patients; however, the presence of tubular dysfunction, which is a risk factor for chronic kidney disease (CKD), has never been examined in vivo. The present prospective longitudinal study aimed to estimate the prevalence of tubular dysfunction alone or with glomerular damage and its evolution after HCV clearance in cirrhotic patients. METHODS: One hundred and thirty-five consecutive Child-Pugh A cirrhotic patients were evaluated before antiviral treatment and 6 months after the end of therapy. Tubular dysfunction was evaluated by urinary alpha1-microglobulin to creatinine ratio (α1-MCR), and glomerular damage was assessed by urinary albumin to creatinine ratio (ACR). RESULTS: Almost all the patients (93.3%) showed a normal or mildly decreased e-GFR (KDIGO-G1/G2-categories). Tubular dysfunction was found in 23.7% (32/135) of patients, co-occurring with glomerular damage in 37.5% (12/32) of cases, while glomerular damage was found in 16.3% (22/135) of patients. In multiple logistic regression, glomerular damage and the concomitant presence of diabetes and hypertension were the only predictors significantly associated with tubular dysfunction. After HCV clearance, patients experienced a significant reduction of α1-MCR levels (21.0 vs 10.5 µg/mg, P = .009) and tubular dysfunction resolved in 57.1% of subjects. CONCLUSIONS: Tubular dysfunction is an unrecognized feature of HCV-related kidney disease in cirrhotic patients and its presence should be primarily investigated in subjects with glomerular damage, diabetes and hypertension, despite normal e-GFR. Tubular dysfunction resolves in the majority of cases after HCV clearance; however, it may persist after antiviral treatment and further studies should evaluate its long-term impact on kidney function.

Expected and Observed Glomerular Filtration Rates in Kidney Transplant Patients Converted to Once Daily Tacrolimus: 10 Years of Follow-up.

The decline of allograft kidney function in the long term remains a significant issue in renal transplantation, with drug nephrotoxicity and cardiovascular complications as important risk factors. Our study aimed to evaluate the estimated glomerular filtration rate (eGFR) trend and metabolic cardiovascular risk factors over 10 years in a cohort of kidney transplant (KT) recipients converted from twice-daily (TD) tacrolimus (Tac) to once-daily (OD)-Tac. We enrolled 55 consecutive KT recipients who had been at the outpatient clinic between 2009 and 2011. Thirty-seven reached the 10-year follow-up. We compared the observed eGFR with the expected eGFR trend described in KT-recipients and monitored blood pressure and metabolic cardiovascular risk factors. The observed eGFR remained stable throughout the complete follow-up (P = .188). The observed decline of eGFR was significantly lower compared with the expected decline for KT patients (P < .001). The blood pressure was maintained within target values. The monitoring of plasma glucose levels demonstrated the stability of median values (P = .686), as well as cholesterol level (P = .250), high-density lipoprotein (HDL) cholesterol (P = .294), and triglycerides (P = .592) throughout the follow-up. The monitoring of tacrolimus plasma level demonstrated that median trough levels remained constant (median values 4.4-5.5 ng/mL) throughout the entire follow-up period (P = .149). We suggest that the reasonable control of metabolic risk factors for cardiovascular disease over long-term follow-up may significantly contribute to the preservation of eGFR compared with the decline expected in KT recipients.