Fabrizio Fabrizi

Chronic hepatitis C virus (HCV) infection is associated with numerous extra-hepatic complications, including neurological and renal manifestations. We describe the case of a 67-year-old Caucasian man with HCV-associated cryoglobulinemic glomerulonephritis, cirrhosis, and hepatocellular carcinoma. The early posttransplant course was complicated by fibrosing cholestatic hepatitis due to recurrent HCV in the graft (HCV RNA up to 44,944,438 IU/mL). Proliferative glomerulonephritis (nephritic and nephrotic syndrome) with mixed cryoglobulinemia (purpura) was also recorded. Seventy-two days after surgery, the patient presented with seizures and arterial hypertension; brain magnetic resonance imaging indicated the diagnosis of posterior reversible encephalopathy syndrome (PRES). PRES responded well to medical treatment with complete resolution of neurological changes. Antiviral therapy (sofosbuvir and ribavirin, six months) gave a sustained viral response with the improvement of cryoglobulinemic symptoms (including glomerular disease). Repeat liver biopsy revealed the regression of cholestatic damage and perisinusoidal fibrosis. The current follow-up shows stable chronic renal failure (serum creatinine: 1.4 mg/dL) and mild nephritic syndrome. The impact of extrahepatic manifestations of HCV on patient outcomes is highlighted from novel observational studies reporting a relationship between HCV cure (as expressed by the sustained viral response) and a decrease in both liver-related and renal complications. Clinical trials evaluating the efficacy and tolerance of novel direct-acting antiviral agents for the management of HCV-associated glomerular diseases are underway.

Introduction Hepatitis C virus (HCV) infection leads to important morbidity and mortality through liver disease and extra-hepatic manifestations. Recent evidence suggests the role of HCV in developing chronic kidney disease (CKD); also, HCV adversely impacts on cardiovascular (CV) disease both in the general population and in patients with CKD. Areas covered All-oral, interferon-free direct-acting antiviral agents are currently available; anti-HCV regimens based on direct-acting antiviral agents (DAAs) are provided with high efficacy and safety and short treatment duration. However, some difficult-to-treat populations still exist including patients with CKD and those who failed previous DAA regimen. Expert commentary Two DAAs regimens (elbasvir/grazoprevir and glecaprevir/pibrentasvir) are now recommended for the treatment of HCV in patients with advanced CKD, these combinations have shown great efficacy, according to two multicenter phase 3 trials (C-SURFER and EXPEDITION-4). These trials reported a minimal impact of baseline resistance-associated substitutions (RASs) on treatment outcomes. The sofosbuvir/velpatasvir/voxaliprevir combination has been recommended as the first-line option for DAAs failures, on the basis of the results given by two randomized clinical trials involving patients who had been previously received DAA-containing regimens (POLARIS 1-4 studies). It has been suggested that clinicians should consider RASs upon the introduction of DAA-based antiviral therapy.

Hepatitis C virus (HCV) infection is now considered a systemic disease due to the occurrence of extra-hepatic manifestations. Among these, the renal involvement is frequent. HCV infection, in fact, is strongly associated with proteinuria and chronic kidney disease (CKD) and negatively affects the prognosis of renal patients. In the last few years, availability of more specific and effective drugs against HCV has dramatically changed the clinical course of this disease. These drugs may provide further advantages in the CKD population as a whole by reducing progression of renal disease, mortality rate and by increasing the survival of graft in renal transplant recipients. The strict pathogenetic and prognostic link between HCV infection and CKD requires an ongoing relationship among the healthcare professionals involved in the treatment of both HCV infection and CKD. Therefore, Scientific Societies involved in the care of this high-risk population in Italy have organized a joint expert panel. The aim of the panel is to produce a position statement that can be used in daily clinical practice for the management of HCV infected patients across the whole spectrum of renal disease, from the conservative phase to renal replacement treatments (dialysis and transplantation). Sharing specific evidence-based expertise of different professional healthcare is the first step to obtain a common ground of knowledge on which to instate a model for multidisciplinary management of this high-risk population. Statements cover seven areas including epidemiology of CKD, HCV-induced glomerular damage, HCV-related renal risk, staging of liver disease in patients with CKD, prevention of transmission of HCV in hemodialysis units, treatment of HCV infection and management of HCV in kidney transplantation.

The advent of direct-acting antiviral agents promises to change the management of hepatitis C in patients with end-stage renal disease, a patient group where the treatment of hepatitis C was historically challenging. We investigated the safety and efficacy of all-oral, interferon-free direct-acting antiviral agents for the treatment of hepatitis C in a ‘real-world’ group of patients with end-stage renal disease. We performed a single-arm, multi-centre study in a cohort (n=30) of patients with advanced chronic kidney disease (mostly on dialysis) who underwent antiviral therapy with direct-acting antiviral agents. The primary end-point was sustained virologic response (serum hepatitis C virus RNA < 15 mIU/mL, 12 weeks after treatment ended). We collected data on on-treatment adverse events, serious adverse events and laboratory abnormalities. In total, 23 (77%) and 7 (23%) patients underwent regular dialysis and had chronic kidney disease at pre-dialysis stage, respectively. Six regimens were adopted: elbasvir/grazoprevir (n = 6), ledipasvir/sofosbuvir ± ribavirin (n = 4), PrOD regimens ± ribavirin (n = 10), simeprevir + daclatasvir (n = 3), sofosbuvir + daclatasvir ± ribavirin (n = 3), sofosbuvir + ribavirin (n = 4). The SVR12 rate was 90% (95% confidence interval, 74%; 96%). A total of 27 (90%) patients achieved SVR12; there were three virologic failures – two were non-responders and one had a viral breakthrough while on therapy. Adverse events occurred in 53% (16/30) (95% confidence interval, 0.39; 0.73) of patients and were managed clinically without discontinuation of therapy or hospitalization. The most common adverse event was anaemia (n = 12) that required blood transfusions in seven individuals; deterioration of kidney function occurred in one (14%). All-oral, interferon-free therapy with direct-acting antiviral agents for chronic hepatitis C virus in advanced chronic kidney disease was effective and well tolerated in a ‘real-life’ clinical setting. Careful monitoring of haemoglobin and serum creatinine during therapy with direct-acting antiviral agents is suggested. Studies are under way to address whether sustained viral response translates into better survival in this population.

The frequency of hepatitis C virus (HCV) infection remains high in patients with chronic kidney disease (CKD) and plays a detrimental role in mortality in this population. According to the latest survey, the adjusted hazard ratio for HCV-positive versus HCV-negative patients on long-term dialysis was 1.12 (95% CI, 1.05 to 1.20) and 1.10 (95% CI, 0.98 to 1.22) for all-cause and cardiovascular mortality, respectively. An impairment on quality of life has also been documented in HCV-infected patients undergoing regular dialysis. Most clinicians have been so far reluctant to treat hepatitis C in patients with advanced CKD, due to concerns regarding low efficacy and safety of interferon-based regimens. The advent of all-oral, direct-acting antivirals (DAAs) has revolutionized treatment paradigms for HCV, including patients with other comorbidities such as CKD. Two combinations of DAAs have been recently approved for the treatment of HCV in advanced CKD: elbasvir/grazoprevir (evaluated in 1 randomized controlled trial) and ombitasvir/paritaprevir/ritonavir/dasabuvir with or without ribavirin (examined in some observational, single-arm studies). These antiviral combinations have provided high safety and efficacy (SVR12 rates >90%) in HCV-infected patients with stage 4–5 CKD. Sofosbuvir, a nucleotide analogue inhibitor of the HCV NS5B polymerase, is the cornerstone of most anti-HCV current regimens but is not currently recommended for patients with severe renal insufficiency (eGFR ; overall, the viral response was satisfactory (SVR12 rates ranging between 58% and 100%) with a few drug-related drop-outs. Studies are in progress to assess whether ribavirin-free antiviral combinations with novel DAAs are a viable option for patients with severe renal impairment and chronic HCV infection.

The frequency of hepatitis C virus infection remains high in renal transplant recipients and plays a detrimental role on survival in this population. According to the latest evidence, the adjusted relative risk of mortality and graft loss for anti-HCV seropositive versus anti-HCV negative renal transplant recipients was 1.85 with a 95% confidence interval (CI) of 1.49 ; 2.31 (P < 0.0001) and 1.76 (95% CI, 1.46 ; 2.11) (P < 0.0001), respectively. Interferon-based regimens have been recommended for the treatment of hepatitis C after renal transplantation only in selected circumstances because of an increased risk of acute rejection due to the immuno-stimulatory properties of interferon. Limited data exist on the treatment of HCV with direct-acting antiviral agents among kidney transplant recipients. To date, the most important evidence comes from the European multicenter study where a large cohort (n=114) of patients with glomerular filtration rate of 40 mL/min/1.73m² received an interferon-free, ribavirin-free combination of direct-acting antivirals (Ledipasvir/Sofosbuvir) for 12 or 24 weeks. A high efficacy [SVR12 rate, 100% (114/114) ] was found even if three serious adverse were observed ; all were determined to be treatment related, one patient interrupted permanently treatment. Also, single-center single-arm observational studies have reported high efficacy and safety of sofosbuvir-based combinations for the treatment of HCV after renal transplant. A decline in through levels of calcineurin inhibitors after completion of antiviral therapy has been found in many patients; an enhanced metabolism of calcineurin inhibitors associated with resolution of liver injury has been suggested. An effective and safe therapy for HCV in kidney transplant recipients might improve the current suboptimal utilization of HCV-positive kidney donors and provide many patients with end-stage renal disease access to HCV-infected donor kidneys.