Seroprevalence and the intensity of the humoral response among HCV chronic infected individuals attending in a public hospital

Abstract

Chronic infection with hepatitis C virus (HCV) is a severe infection that may progress to cirrhosis and hepatic decompensation.
Objectives: To determine the prevalence of HCV infection amongst screened individuals, between September 2007 and September 2009 to determine the relationships between serum antibody levels and the presence of viral RNA.
Methods: Serological results of the research to anti HCV antibodies by enzyme-linked immunosorbent assay-ELISA (BioMérieux ®) of 4536 subjects were analyzed retrospectively. The results of molecular research (Cobas AMPLICOR HCV Roche Diagnostics ®) of 79 patients were extracted from medical records, and genotypes 1 and 3 were the most frequent. The probability of serologic results to be related to molecular analysis was verified by ROC curve constructed for different values of Index (OD sample / OD cutoff ELISA).
Results: Of samples for which the molecular test was performed, 82.3% confirmed the presence of HCV RNA. Positive predictive values (PPV) and negative predictive values (NPV) for the presence of viremia, considering Index values of 4.0 3.0 and 2.0 were: for the Index 4.0 sensitivity (S) of 62%, specificity (Sp) 64%, PPV 89%, NPV of 27%. In the Index 3.0 S = 93.0%; E = 36.0%, PPV 87%, NPV 55%. In the Index 2.0% S=100, E=21%, PPV 85%; VPN 100%.
Conclusion: It can be inferred that there is high probability of patients with serological reaction for screening anti-HCV reagent, presenting Index lower than 2.0 have suppressed HCV infection, and index above 4.0 have present viremia.