Metabolic disorders induced by PNPLA3 and TM6SF2 gene variants affect chronic kidney disease in patients infected with non-genotype 3 hepatitis C virus

BACKGROUND

Patients with chronic hepatitis C virus (HCV) infections differ in their risk for metabolic disorders and chronic kidney disease (CKD). The aim of this study was to investigate the effect of metabolic disorders induced by genetic factors on CKD in HCV-infected patients.

METHODS

Patients with chronic non-genotype 3 HCV infection with or without CKD were examined. PNPLA3 and TM6SF2 variants were determined using high-throughput sequencing. The relationships of variants and different combinations with metabolic disorders were analyzed in CKD patients. Univariate and multivariate analyses were used to identify factors associated with CKD.

RESULTS

There were 1022 patients with chronic HCV infection, 226 with CKD and 796 without CKD. The CKD group had more severe metabolic disorders, and also had higher prevalences of liver steatosis, the PNPLA3 rs738409 non-CC genotype, and the TM6SF2 rs58542926 CC genotype (all P < 0.05). Relative to patients with the PNPLA3 rs738409 CC genotype, patients with the non-CC genotype had a significantly decreased eGFR and a greater prevalence of advanced CKD (CKD G4-5). Patients with the TM6SF2 rs58542926 CC genotype had a lower eGFR and a higher prevalence of CKD G4-5 than those with the non-CC genotype. Multivariable analysis indicated that multiple metabolic abnormalities, including liver steatosis and the PNPLA3 rs738409 C > G variant, increased the risk of CKD, but the TM6SF2 rs58542926 C > T variant decreased the risk of CKD.

CONCLUSION

Specific PNPLA3 rs738409 and TM6SF2 rs58542926 variants are independent risk factors for CKD in patients with chronic HCV infections and are associated with the severity of renal injury.

High rate of acute kidney injury in patients with chronic kidney disease and hepatitis C virus genotype 4 treated with direct-acting antiviral agents

BACKGROUND

Direct-acting antivirals (DAAs) have significantly improved the efficacy and safety of treating chronic hepatitis C (CHC), but their effectiveness and safety among patients with chronic kidney disease (CKD) remains poorly understood. Sofosbuvir/daclatasvir regimen is supposed to be used for patients with creatinine clearance more than 30 mL/min, while ombitasvir/paritaprevir/ritonavir regimen is used for patients with creatinine clearance less than 30 mL/min.

AIM

The aim of the study was to assess the safety and efficacy of DAAs among patients with CKD.

METHODS

Eighteen CKD stage 2-3b patients received sofosbuvir for 3 months. In addition, 42 CKD stage-4 patients received ritonavir-boosted paritaprevir plus ombitasvir for 3 months. Finally, ribavirin was added for 30 of them.

RESULTS

The patients'age was 49.2 ± 12 years. Baseline serum creatinine was 3.76 ± 1.67 mg/dL. Fifty patients were HCV genotype 4. A 3-month sustained viral response was achieved in 56 patients and 49 patients achieved a 6-month viral response. There were 11 relapsers. Acute kidney injury (AKI) upon CKD (AKI/CKD) occurred in 28 patients, of which 20 needed hemodialysis. Fifteen/28 recovered from AKI, whereas 13 were maintained on hemodialysis. In multivariate analysis, there were only two independent risk factors for developing AKI/CKD, i.e., being cirrhotic as defined by baseline abdominal ultrasound findings [odds ratio 4.15 (1.33-12.97); p = 0.013] and having had as DAA therapy OMV/PTV/RTV [odds ratio 7.35 (1.84-29.35); p = 0.001].

CONCLUSION

Treatment of HCV among stage 2, 3a, and 3b patients was achieved safely with a sofosbuvir-based regimen. We recommend that stage-4 patients wait until starting hemodialysis or transplantation.

APASL clinical practice recommendation: how to treat HCV-infected patients with renal impairment?

Chronic hepatitis C virus (HCV) infection is common among patients with chronic kidney disease (CKD) and those on hemodialysis due to nosocomial infections and past blood transfusions. While a majority of HCV-infected patients with end-stage renal disease are asymptomatic, some may ultimately experience decompensated liver diseases and hepatocellular carcinoma. Administration of a combination of elbasvir/grazoprevir for 12 weeks leads to high sustained virologic response (SVR) rates in patients with HCV genotypes (GTs) 1a, 1b or 4 and stage 4 or 5 CKD. Furthermore, a combination of glecaprevir/pibrentasvir for 8-16 weeks also results in high SVR rates in patients with all HCV GTs and stage 4 or 5 CKD. However, these regimens are contraindicated in the presence of advanced decompensated cirrhosis. Although sofosbuvir and/or ribavirin are not generally recommended for HCV-infected patients with severe renal impairment, sofosbuvir-based regimens may be appropriate for those with mild renal impairment. To eliminate HCV worldwide, HCV-infected patients with renal impairment should be treated with interferon-free therapies.

Metabolic Dysregulation in Hepacivirus Infection of Common Marmosets (Callithrix jacchus)

Chronic hepatitis C has been associated with metabolic syndrome that includes insulin resistance, hepatic steatosis and obesity. These metabolic aberrations are risk factors for disease severity and treatment outcome in infected patients. Experimental infection of marmosets with GBV-B serves as a tangible, small animal model for human HCV infection, and while virology and pathology are well described, a full investigation of clinical disease and the metabolic milieu is lacking. In this study six marmosets were infected intravenously with GBV-B and changes in hematologic, serum biochemical and plasma metabolic measures were investigated over the duration of infection. Infected animals exhibited signs of lymphocytopenia, but platelet and RBC counts were generally stable or even increased. Although most animals showed a transient decline in blood glucose, infection resulted in several fold increases in plasma insulin, glucagon and glucagon-like peptide 1 (GLP-1). All infected animals experienced transient weight loss within the first 28 days of infection, but also became hypertriglyceridemic and had up to 10-fold increases in adipocytokines such as resistin and plasminogen activator inhibitor 1 (PAI-1). In liver, moderate to severe cytoplasmic changes associated with steatotic changes was observed microscopically at 168 days post infection. Collectively, these results suggest that GBV-B infection is accompanied by hematologic, biochemical and metabolic abnormalities that could lead to obesity, diabetes, thrombosis and atherosclerosis, even after virus has been cleared. Our findings mirror those found in HCV patients, suggesting that metabolic syndrome could be conserved among hepaciviruses, and both mechanistic and interventional studies for treating HCV-induced metabolic complications could be evaluated in this animal model.

Long-term response to peginterferon in hepatitis C virus-associated nephrotic syndrome from focal segmental glomerulosclerosis

Hepatitis C virus (HCV) infection is a global public health problem. Chronic HCV infection is an important cause of chronic liver disease. Since the first reported association between HCV and membranoproliferative glomerulonephritis (MPGN) in 1993, HCV has been described with other types of glomerular diseases, although less frequently. Focal segmental glomerulosclerosis (FSGS) is one such glomerular disease that has been rarely reported in association with HCV. Antiviral therapy with interferon and ribavirin has been shown to be beneficial in HCV-associated MPGN. The optimal therapy of HCV-associated FSGS is not currently known. To our knowledge, long-term response to pegylated interferon monotherapy in treatment of HCV-associated FSGS has not been reported. We report an adult patient with HCV-associated FSGS who presented with nephrotic syndrome and renal failure. Treatment with pegylated interferon alfa-2a monotherapy resulted in sustained virological response with a clinical remission of nephrotic syndrome and stabilization of renal function. Patient continued to remain in clinical remission of nephrotic syndrome with stable renal function, 5 years after treatment. We also briefly review the literature on HCV-associated glomerular diseases, particularly HCV-associated FSGS.