Outbreak of hepatitis C virus infection during sclerotherapy of varicose veins: Long-term follow-up of 196 patients (4535 patient-years)

Background/Aims The aim of this study was to describe the natural history of a HCV infection outbreak in 196 patients who had sclerotherapy by a same physician and to confirm patient-to-patient transmission using phylogenetic analysis in a large series of patients. Methods Demographic information included clinical and biological parameters. Fibrosis evaluation was performed using liver biopsy or transient elastography. Follow-up was maintained until death, or the end of the observation period. In order to determine if the virus had been transmitted between the HCV genotype 2 patients, sequence analysis was undertaken of a part of the NS5b region of the genomes in samples of patients. Results The mean duration of follow-up was 23.1 ± 6.7 years (4535 patient-years). In patients with fibrosis evaluation, 55.7% had no or mild fibrosis and 44.3% had significant fibrosis. No patient died from HCV-related disease. Nucleotide sequence analysis of a part of the NS5b region revealed that patients were all infected with the same HCV subtype (genotype 2d). The most evident feature of the tree is the clustering of all patients involved in the outbreak without any unrelated isolates. Conclusion This study emphasizes the risk for nosocomial spread of HCV during intravenous therapy.