Introduction
Hepatitis C virus (HCV) was discovered 25 years ago [1] and is now about to get a cure. In the meantime, the C virus has induced tremendous morbidity and mortality mainly due to liver complications (cirrhosis, hepatocellular carcinoma). However, many extrahepatic manifestations [2] have been reported for chronic HCV infection with increased related morbidity and mortality, including cardiovascular diseases, type 2 diabetes and insulin resistance, neurocognitive dysfunction, systemic vasculitis, B cell non-Hodgkin lymphoma and chronic kidney disease [3]. Today, some new challenges remain, particularly with regard to specific populations suffering from HCV infection, such as renal patients. Our article focuses on the specificities of screening, monitoring, assessing, treating and following up, in the context of HCV infection, persons living with chronic kidney disease, end-stage renal failure or a kidney graft.
This article is based on previously conducted studies and does not involve any new studies of human or animal subjects performed by any of the authors.
Epidemiology of Hepatitis C Virus Infection in Renal
Patients
Approximately 170 million people are infected with HCV worldwide and 2.35% of the total world population [4]. In dialysis patients, the prevalence of HCV infection has evolved dramatically over the last 10 years. In 2004, the Dialysis Outcomes and Practice Patterns Study (DOPPS) published the largest study analyzing the HCV serological status in 8615 randomly selected hemodialysis patients treated in 308 dialysis facilities (in 8 countries in Europe, HCV USA and Japan) [5]. It showed the HCV antibody prevalence to be 14.7% when unadjusted and 10.4% when adjusted for age, gender, race, time with end-stage renal disease, and alcohol or drug abuse in the past 12 months. The updated DOPPS study [6] found a very low prevalence of HCV treatment in dialysis patients as only 1% of the 4589 patients with available prescription data were receiving HCV medications. Among a subset of 617 HCV patients known to be on the waiting list for renal transplantation, only 3.7% were receiving HCV treatment. In the DOPPS study, the seropositivity for HCV was associated with black race [odds ratio (OR) = 1.93, P < 0.0001], male gender (OR = 1.18, P = 0.01), diabetes mellitus (OR = 1.18, P = 0.03), a history of gastrointestinal bleeding (OR = 1.22, P = 0.06), HBV infection (OR = 2.56, P < 0.0001) and prior renal transplant (OR = 1.34, P = 0.01). Drug and alcohol abuse, as reported during the 12 months prior to data collection, was also associated with HCV seropositivity (OR = 2.44, P < 0.0001 and 1.75, P = 0.0001, respectively). At that time, the risk of seroconversion was variable despite infection control measures, and HCV outcomes varied by patient characteristics, country and hemodialysis facility practice patterns. No consensus was available with regard to the need for hemodialysis patient isolation and dedicated dialysis machines to prevent HCV transmission, in addition to blood-borne precautions [5]. Adjusted HCV seroconversions/100 patient-years ranged from 1.2 (0.7–2.0) in the UK to 3.9 (2.9–5.2) in Italy. In 55.6% of facilities, the mean seroconversion rate was 0 per 100 patient-years.