title: TT virus infection in patients with fulminant hepatic failure.
abstract: OBJECTIVE
  A new DNA virus, which has been designated the TT virus, was discovered in 1997. It is not clear whether TT virus is a cause of any of the types of hepatitis. We conducted a case-control study to test the hypothesis that the presence of TT virus is a necessary condition for the development of fulminant hepatic failure in people who have non-A, -B, or -C hepatitis.
  
  
  METHODS
  We studied 55 patients with fulminant hepatic failure [28 men, 27 women, mean (+/- SD) age, 47 +/- 15 yr], 32 patients with acute hepatitis (18 men, 14 women, mean age, 38 +/- 15 yr), and 200 healthy subjects (106 men, 94 women, mean age, 42 +/- 14 yr). TT virus DNA was detected in sera by a nested polymerase chain reaction using a primer set for genotype 1.
  
  
  RESULTS
  TT virus was more frequently detected in patients with fulminant hepatic failure [in 33 of 55 (60%); 95% confidence interval (CI), 47-73%] than in those with acute hepatitis [in 8 of 32 (25%); 95% CI, 10-40%; p = 0.0016] or in healthy subjects [in 50 of 200 (25%); 95% CI, 19-31%; p < 0.0001]. TT virus was detected at a significantly higher rate in non-A, -B, or -C fulminant hepatic failure [in 18 of 22 (82%); 95% CI, 66-98%] than in fulminant hepatic failure of A, B, or C type [45%, 28-62%, 15/33; p = 0.007] or in non-A, -B, or -C acute hepatitis [24%, 3-44%, 4/17; p = 0.0003]. The logistic regression analysis selected TT virus (p = 0.0009), age (p = 0.0116), and etiology (p = 0.0309) as independent variables associated with fulminant hepatic failure (coefficient of determination, 0.2335).
  
  
  CONCLUSIONS
  TT virus comparatively plays a role in the pathogenesis of non-A, -B, or -C fulminant hepatic failure.
authors.affiliation: Second Department of Internal Medicine, Showa University, School of Medicine, Tokyo, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Shibata
authors.forename: T
authors.initials: T
authors.lastname: Morizane
authors.forename: T
authors.initials: T
authors.lastname: Baba
authors.forename: K
authors.initials: K
authors.lastname: Inoue
authors.forename: K
authors.initials: K
authors.lastname: Sekiyama
authors.forename: M
authors.initials: M
authors.lastname: Yoshiba
authors.forename: K
authors.initials: K
authors.lastname: Mitamura
mesh_terms: D000208:Acute Disease; D000328:Adult; D016022:Case-Control Studies; D004266:DNA Virus Infections / Q000150:complications*; D005260:Female; D006505:Hepatitis / Q000821:virology; D006801:Humans; D017093:Liver Failure / Q000209:etiology / Q000821:virology*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D022783:Torque teno virus / Q000302:isolation & purification*