Similar frequency of TT virus infection in patients with liver enzyme elevations and healthy subjects

TT virus (TTV) is a novel DNA virus that has been identified in patients wi th posttransfusional hepatitis of unknown aetiology. However, its pathogeni c role in liver injury remains unclear. To determine its frequency and clin ical impact in cryptogenic liver diseases, we investigated the TTV prevalen ce in patients with liver enzyme elevations of unknown aetiology and in hea lthy subjects. Fifty-four patients (33 male, 21 female) who have been follo wed up for elevated ALT/AST levels of unknown aetiology and 118 healthy sub jects (99 male and 19 female) were included in the study. TTV DNA was inves tigated by the polymerase chain reaction. Other possible causes of transami nase elevation were excluded in detailed biochemical and serological tests. A liver biopsy was performed in 45 patients. TTV DNA was detected in 46 pa tients with liver enzyme elevations (85.1 %) and in 94 healthy subjects (79 .6%). There was no statistical difference between the groups (p=0.51). Hist ological examination of the liver revealed no specific change in TTV DNA po sitive patients that could be attributed to this virus infection. These res ults showed that TTV is a common virus in patients with liver enzyme elevat ion of unknown aetiology and even among healthy subjects in our geographica l area. TTV infection is therefore widespread in the general population and does not seem to be associated with liver damage.