[Relative risk of hepatitis C virus transmission in polytransfused patients].

Hepatitis C virus (HCV) has been shown to be responsible for a significant proportion of hepatitis cases among patients undergoing frequent blood transfusions. The prevalence in blood serum of anti-HCV antibodies was studied in 48 patients who had undergone dialysis and multiple blood transfusions. In 42 of these patients the average number of transfusions during their treatment was 11.2. The patients were stratified into four groups according to the number of transfusions received (I: < 5, II:6-9, III:10-15 and IV > 15). Odds ratios were used in order to estimate the probability of finding anti-HCV antibodies in groups II, III and IV in relation to the least exposed group I. Anti-HCV antibodies were found in 59% of patients receiving transfusions. As grouped by increasing number of transfusions, each set showed 16, 66, 62.5 and 100% presence of anti-HCV antibodies, respectively. This shows a direct correspondence between the number of transfusions and the serum-born incidence of anti-HCV antibodies. These results closely coincide with those of a similar study, done in the city of Cordoba, Argentina, in 1992. The two studies confirm the necessity to check blood units in order to discard those with anti-HCV antibodies.