Respuesta al comentario sobre el Manejo de la infección por el virus de la hepatitis C en la enfermedad renal crónica Translated title: Response to the comment made on Treatment of HCV infection in chronic kidney disease

Hepatitis C virus (HCV) remains a problem within hemodialysis units. This study measures HCV prevalence and seroconversion rates across seven countries and investigates associations with facility-level practice patterns. The study sample was from the Dialysis Outcomes and Practice Patterns Study (DOPPS), a prospective, observational study of adult hemodialysis patients randomly selected from 308 representative dialysis facilities in France, Germany, Italy, Japan, Spain, the United Kingdom, and the United States. Logistic regression was used to model odds of HCV prevalence, and Cox regression was used to model time from study entry to HCV seroconversion. Mean HCV facility prevalence was 13.5% and varied among countries from 2.6% to 22.9%. Increased HCV prevalence was associated with longer time on dialysis, male gender, black race, diabetes, hepatitis B (HBV) infection, prior renal transplant, and alcohol or substance abuse in the previous 12 months. Approximately half of the facilities (55.6%) had no seroconversions during the study period. HCV seroconversion was associated with longer time on dialysis, human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS), HBV infection, and recurrent cellulitis or gangrene. An increase in highly trained staff was associated with lower HCV prevalence (OR = 0.93 per 10% increase, P= 0.003) and risk of seroconversion (RR = 0.92, P= 0.07). Seroconversion was associated with an increase in facility HCV prevalence (RR = 1.36, P < 0.0001), but not with isolation of HCV-infected patients (RR = 1.01, P= 0.99). There are differences in HCV prevalence and rate of seroconversion at the country and the hemodialysis facility level. The observed variation suggests opportunities for improved HCV outcomes.

Hepatitis C virus (HCV) infection is a significant problem in the management of haemodialysis patients. A high prevalence of HCV infection in haemodialysis patients has been reported. Risk factors such as the number of blood transfusions or duration on haemodialysis have been identified. To determine the prevalence of HCV by antibody testing and HCV-RNA determination by polymerase chain reaction (PCR) in haemodialysis patients. Furthermore, liver function tests were performed and epidemiological data were obtained to determine risk factors for HCV in this cohort of patients. A total of 2796 patients from 43 dialysis centres were enrolled. The overall prevalence of HCV (HCV antibody and/or HCV-RNA positivity) was 7.0% (195 patients). Antibody positivity occurred in 171 patients (6.1%). Viraemia was detectable in 111 patients (4.0%). Twenty four of 111 HCV RNA positive patients (21.6%) were negative for HCV antibodies. Thus 0.8% of the entire study population was HCV positive but could not be diagnosed by routine HCV antibody testing. Major risk factors identified by a standard questionnaire in 1717 of 2796 patients were the number of blood transfusions individuals had received and duration of dialysis, the latter including patients who received no blood transfusions. Sequencing of the 5'untranslated region of the genome showed a dominant genotype 1 (77.6%) within the cohort. Further reverse transcription-PCR of the NS5b and core region were performed to document phylogenetic analysis. Comparing nucleic acid sequences detected by PCR, no homogeneity was found and thus nosocomial transmission was excluded. HCV is common in German haemodialysis patients but screening for HCV antibodies alone does not exclude infection with HCV.

Hepatitis C virus (HCV) infection is common in kidney transplantation and is known to affect long-term patient and graft survival, as is time in renal-replacement therapy (RRT). The aim of this study was to investigate HCV in relation to time in RRT and its impact on outcome after transplantation. A follow-up cohort study using Kaplan-Meier analysis and Cox proportional hazards model was performed in 545 kidney and 26 kidney-pancreas transplant recipients receiving transplants between 1989 and 1997, with last follow-up on December 31, 2002. HCV status at transplantation and time in RRT were analyzed. Time in RRT was significantly longer (P<0.0001), and previous transplantations were more common (P=0.04) in the HCV-positive group. HCV significantly reduced patient (P=0.0012) and graft survival (P=0.0003) after transplantation. Adjustment for age, sex, diabetes, previous transplantations, type of transplant, and time in RRT resulted in a relative risk (RR) for death of 2.23, 1.92, and 1.07 for HCV, diabetes, and age, respectively. The RR for graft loss was 1.96 and 1.03 for HCV and age. Sex, previous transplants, and time in RRT did not affect HCV as an independent risk factor for patient or graft survival. The leading cause of death was cardiovascular disease in both groups. HCV was, in our series, more important than time in RRT for patient death and graft loss posttransplant. Successful pretransplant antiviral therapy could be more beneficial for HCV-infected patients rather than early transplantation for long-term outcome, but this needs to be studied prospectively.