[Epidemiologic study of infection by hepatitis C virus in a hemodialysis unit]

To analyze the prevalence of infection, the frequency of HCV genotypes and the epidemiology characteristics among the patients in hemodialysis treatment in one 25 years old hospital hemodialysis center and one 15 years old secondary unit by a transversal cross-section study in 1998.

171 hemodialyzed-patients were studied. Patients sera were analyzed by the presence of HCV antibodies anti-VHC by a enzymoimmunoassay (Abbott Cientifica) and the presence of antibodies was confirmed by a line immunoassay (Inno-LIA HCV AbIII) and by the presence of VHC-RNA by reverse transcriptase PCR (Cobas Amplicor HCV). Genotypes were determinate by reverse hybridization (Inno-LIA HCV III).

Fifty (29.2%) of the patients were HCV antibody positive. Forty-five (26.3%) were HCV-RNA positive, all of them with antibodies positive. The distribution of genotypes was: 1b, 34 (75.5%); 4f, 4 (8.9%); 1a, 3 (6.7%); 1, 3 (6.7%) and 1 case could not be typed (2.2%). In 14 patients (28.0%), seroconversions were documented Twenty-one patients (42.0%) were diagnosed when the routine tests were available and 15 patients (30.0%) were diagnosed pre-dialysis. The multivariate analysis showed that the risk of HCV infection was greater for patients who had been more 8 years on dialysis (OR: 6.22; 95% CI: 1.24-31.07).

Data presented indicate that the prevalence of HCV infections in our hemodialysis units and the number of seroconversions were high and the HCV subtype 1b was more frequent; because of this, the screening by both serological and molecular methods is necessary, at least twice a year, to identify all the infected patients. Besides, we think that is necessary to increase the control of the completion of the Universal Precautions.