HCV genotypes in intravenous drug addicts in a cohort of Argentine patients.

Intravenous drug addiction (IVD) is an unfrequent risk factor in Argentina, representing less than 10% of patients (pts) with chronic HCV infection se en in our Unit. In order to study the genotypes (Gt) in IVD and compare the m with a non drug addicted control population, 68 pts with a history of IVD were enrolled in this study and compared with 68 non drug addict (NDA) pts with chronic HCV, with similar age and gender distribution. In ail pts a l iver biopsy was performed. Genotyping was done by INNO UPA (Innogenetics, B elgium). Mean age in both groups was 35 +/- 7.8 years and 50 were males. No difference was observed between both groups in the prevalence of Gt1a, Gt2 a/c and in those with mixed infections. The prevalence of G11b in IVD was 1 9.1% and in NDA 38.2% (p = 0.0228). A highly significant difference was als o observed in the prevalence of Gt3a, of 42.6% in IVD and only 11.8% in NDA (p = 0.0001). Gt1a was the second most frequent genotype in IVD pts (26.5% ). Simultaneous HN infection was present in 8 IVD pts (11.8%) and in none o f NDA group. Liver biopsies showed a higher prevalence of mild chronic hepa titis in NDA (57.3%) than in IVD (32.4%) (p = 0.0058). Severe chronic hepat itis with advanced fibrosis or cirrhosis was more frequent in the Gt3 of th e group with IVD when compared with Gt3 of the NDA group. It can be conclud ed that in accordance with other geographical areas, Gt3a is far more preva lent in intravenous drugs addicts than in the general population in Argenti na where Gt1b is more frequent. Mild forms of chronic hepatitis are less fr equent in IVD. In spite of the relatively small group with HCV co-infection with HIV, it seems important to note that 2/8 (25%) showed severe hepatiti s C or cirrhosis.