Background:  Discordant results of anti-hepatitis C virus (HCV) antibody (Ab) and hepatitis C RNA (HCV Ab -, HCV RNA +) have been reported in individuals co-infected with HIV and HCV, mainly in cohorts of patients infected via the parenteral route. Our objective was to determine if these findings could be duplicated in a patient population more representative of the HIV epidemic in the United States.

Methods:   HIV-infected patients in our clinic were prospectively evaluated for their demographics, risk factors, anti-HCV Ab (Abbott), COBAS AMPLICOR HCV Qualitative RNA  (Roche), Amplicor HIV-1 Monitor (Roche), and CD4 counts. Genotyping was performed on all confirmed HCV RNA positive samples. 

Results:   A total of 221 patients (82% male, mean age 43 years) were enrolled.   HIV/HCV risk factors included: men who have sex with men (MSM) 62%, heterosexual sex 22%, IVDU 9%, and history of transfusion 3%. The mean and median CD4 count were 544 and 500 cells/mm³ respectively. The median nadir CD4 count was 233 cells/mm³, with a nadir to baseline of 48 months.  The mean and median viral load were 187 and 15,910 copies/mL, respectively.  HCV Ab was confirmed positive in 35/221 (16%) patients.  27/35 (77%) of HCV Ab+  patients. had HCV viremia. HCV genotypes were:  1A (56%), 1B (24%), 2A (4%), 2B (4%), 4 (4%), and 2A/2B (8%). There were no discordant results of HCV Ab vs HCV RNA testing.

Conclusions:  In a cohort of HIV-infected patients representative of the epidemic in the United States, the HCV Ab is a reliable screening test for the presence of HCV infection.