Clinical significance of TT virus infection in maintenance hemodialysis patients of an endemic area for hepatitis C infection

Clinical significance of TTV infection was analyzed in Egyptian hemodialysis (HD) patients. Forty-seven Egyptian patients on maintenance HD and 50 age-matched volunteer blood donors were investigated. TT virus (TTV) DNA detection and genotyping were performed using a semi-nested polymerase chain reaction with specific primers. The prevalence of TTV DNA in patients on HD (66%) was significantly (P < 0.001) higher than in blood donors (24%) with genotype 1b predominance (89%) in both. Clinical background including mean age, sex, history of blood transfusion, and positive markers for either hepatitis B virus (HBV) or hepatitis C virus (HCV) did not differ between TTV DNA positive and negative HD patients. However, the mean duration of HD was significantly (P = 0.032) shorter in the TTV positive patients (28 ± 19 months) than in the negative ones (45 ± 34 months). Mean alanine aminotransferase level in patients with HCV infection alone (41 ± 24 IU/l) did not differ from that in patients with both co-infection (33 ± 28 IU/l), but was significantly higher than that in patients with TTV infection alone (26 ± 10 IU/l). Occurrence of chronic hepatic changes in patients with TTV infection alone (7%) was significantly less common than those with HCV infection alone (100%, P < 0.001) or those with both co-infection (100%, P < 0.001). Serum level of HCV core protein was similar between patients with HCV infection alone and those with co-infection with TTV. In conclusion, the prevalence of TTV infection is high in Egyptian patients on regular HD, especially with shorter duration on HD. No clinical significance of TTV virus could be elicited in HD Egyptian patients; neither it showed any clinical impact as a co-infection with HCV. © 2002 Elsevier Science Ireland Ltd. All rights reserved.