Effect of interferon free antiviral therapy on glomerular and tubular kidney involvement in HCV Child-A cirrhosis

Background Hepatitis C virus (HCV) infection is associated with increased risk of renal disease. While HCV-related glomerular damage is well characterized, limited data are available on HCV-related tubular damage and its evolution after HCV clearance. The aim of our study was to evaluate the effect of viral eradication after direct anti-viral agents (DAAs) treatment on glomerular and tubular damage in patients with HCV-cirrhosis. Methods 94 Child- Pugh-A pts with cirrhosis treated with DAAs were consec- utively enrolled. Estimated glomerular filtration rate (e-GFR assessed by CKD-EPI equation), urinary albumin to creatinine ratio (ACR), urinary α1-microglobulin to creat- inine ratio (α1MCR) and fractional excretion of sodium (FeNa) were evaluated at baseline and six months treatment (FU-6). Glomerular damage was defined as ACR>30 mg/g and tubular damage was defined as α1MCR>14 mg/g and/or FeNa>1%. Results At base- line, glomerular and/or tubular damage occurred in 39 pts (41.5%): 20 pts had only tubular (51.3%), 9 pts had only glomerular (23.1%) and 10 pts had both tubular and glomerular (25.6%) involvement. Patients with renal damage showed significantly lower e-GFR values than patients without damage (85.1±5.8 mL/min/1.73m2 vs 95.2±15.2 mL/min/1.73m2, p<0.05). Among 33 exam- ined pts with baseline tubular involvement (3 pts died,2 relapsed,1 was lost to FU) who achieved SVR, a significant reduction of both α1MCR and FeNa was observed at FU-6 (table), while evidence of tubular involvement was still present only in 11 pts(33.3%;p<0.001). Out of 19 pts with baseline glomerular involvement, a significant FU-6 reduc- tion of ACR occurred in the 13 patients without diabetes (p=0.001), 11 of whom (84.6%) showed normal ACR values. Interestingly, no change occurred in the 6 patients with diabetes (table). Conclusions Our study is the first to demonstrate that HCV-related tubular damage may reverse after successful antiviral therapy. Instead, glomer- ular damage may improve after HCV clearance only in the absence of a competing diabetes-induced damage.