Abstract
Previous reports from the United States indicate that as many as 40% of patients with chronic hepatitis C virus (HCV) have no identifiable risk factor for HCV infection. To determine whether the same is true of Canadian patients with chronic HCV the records of 89 anti-HCV positive patients referred to the authors' tertiary care centre for evaluation of liver disease were reviewed. Each patient had been specifically asked about the following risk factors: previous blood transfusions; intravenous drug abuse; homosexual activity; sexual promiscuity (multiple sexual partners or a history of sexually transmitted diseases); tattoos made with nonsterile techniques; and ear piercing using nonsterile techniques. The results of the study revealed that 76 of 89 patients (85%) had at least one risk factor for HCV exposure, 38 (43%) had only one risk factor, 19 (21%) had two, 12 (14%) had three and the remaining three patients (3%) had four. The most common risk factor was a history of intravenous drug abuse (30 of 89 patients, 34%) followed by sexual promiscuity (28, 32%), previous blood transfusions (21, 24%), tattoos (17, 19%), homosexual contacts (seven, 8%) and ear piercing (five, 6%). Contrary to a recent report identifying sexual contact as an independent risk factor for HCV infection, only four cases (5%) were found where sexual promiscuity was identified as the only risk factor. In conclusion, these findings indicate that a possible source of HCV infection can be identified in a large majority of Canadians referred to an urban centre with chronic HCV infection.