EVALUATION OF SEXUAL TRANSMISSION IN PATIENTS WITH CHRONIC HEPATITIS-C INFECTION

Background: The transmission of hepatitis C virus (HCV) by parenteral exposure is well documented. However, a proportion of patients with ac ute or chronic HCV infection have an unknown source of infection. Obje ctives: The purpose of this study is to evaluate the role of sexual tr ansmission in HCV infection. Study design: 68 patients (median age, 50 years) with chronic hepatitis C and their spouses were tested for the presence of antibody to HCV (anti-HCV) by multi-antigen and chimeric C25 antigen enzyme immunoassays and for HCV RNA by the polymerase chai n reaction. Information on sexual activity and risk factors for HCV in fection were obtained from all couples via a questionnaire. Results: A ll index patients were positive for both anti-HCV and HCV RNA. Antibod y to HCV was detected in four (5.9%) of their spouses. One anti-HCV-po sitive spouse had a history of blood transfusion while the other three (4.4%, 95% CI = 1.5-12.2%) had no known risk factors for HCV infectio n and thus may have been exposed to HCV via sexual transmission. Two o f these 3 spouses had positive serum HCV RNA and had identical HCV gen otype to the index patients. The length of sexual exposure was signifi cantly longer in the couples who both were anti-HCV-positive than in p atients whose spouses were anti-HCV negative (median: 25 vs. 10 years, P = 0.02, Mann-Whitney test). In our 68 index patients, 96% had antib odies to the recombinant proteins from the C22 (core) and C33C (NS3) r egions, and 82% and 76% had antibodies to the proteins from the NS5 an d C100-3 (NS4) regions. Identical anti-HCV profiles were noted in two of the four anti-HCV-positive couples. Conclusions: Our results indica te that sexual transmission, although uncommon, should be considered a s a risk factor for HCV infection, especially in spouses who have had long-term intimate relationships with a chronic hepatitis C patient.