Prevalence of TT virus infection in Italian dialysis patients

A novel DNA virus, transfusion-transmitted virus (TTV) is identified from the serum of a patient from acute hepatitis non-A-E. Few reports have been published on patients with renal disease. Patients on dialysis were at high risk of blood-borne viral infections and little is known about the prevalence of this virus in dialysis patients. In order to verify the prevalence of infection from TTV in these patients, we have examined the incidence of TTV in Italian patients with dialysis.

Serum samples of 85 patients and 65 healthy individuals were examined. In order to evidence the presence of the TTV virus, a method of the seminested polymerase chain reaction (PCR) with TTV-specific primers derives from the N22 region deIl'ORF-1 of the virus has been used and products were analyzed by agarose-gel electrophoresis. All serum samples were also analyzed to markers HBV and HCV.

The prevalence of TTV DNA in dialysis patients [35/85 (41.7%)] was significantly higher than in healthy population [7/65 (10.7%)]. Among TTV positive dialysis patients, HCV coinfection was present in six cases. The positivity rate for TTV-DNA tends to increase with age.

Transfusion-transmitted virus had a high prevalence in Italian-dialysis patients. In our study the virus did not have an important clinical effect on patients; but remains the possibility that it may aggravate liver disease caused by HCV. However, the question of whether TTV infection might have a possible effect on dialysis patients requires further investigation in larger groups.