Blood, Vol. 95 No. 1 (January 1), 2000:
pp. 347-351
Natural history of the TT virus infection through follow-up of
TTV DNA-positive multiple-transfused patients
Jean-Jacques Lefrère,
Françoise Roudot-Thoraval,
François Lefrère,
Alain Kanfer,
Martine Mariotti,
Joelle Lerable,
Micheline Thauvin,
Guillaume Lefèvre,
Philippe Rouger, and
Robert Girot
From the Institut National de la Transfusion Sanguine, and
Faculté Saint-Antoine, Université Pierre et Marie Curie
75012 Paris, France; Service de Santé publique, Hôpital
Henri-Mondor, Créteil, France; Service d'Hématologie
Adultes, Hôpital Necker, Paris, France; and the Hôpital de
jour de médecine, Laboratoire de Biochimie, and Laboratoire
d'hématologie, Hôpital Tenon, 75020 Paris, France.
Little is known about the natural history and the pathogenicity of
the TT virus (TTV). We present our findings of a cross-sectional study
based on the TTV DNA screening of 173 multiple-transfused patients and
a longitudinal study based on the follow-up of TTV DNA-positive
patients. Overall, 48 patients (27.7%) tested positive for TTV DNA.
The influence of the number of blood donor exposures on the prevalence
of blood-borne viral infection indicates that TTV, hepatitis C virus
(HCV), and an RNA virus known as GB virus C/hepatitis G virus
(GBV-C/HGV) share a parenteral transmission, but that TTV, in contrast
to the 2 other viruses, is also transmitted by at least another
efficient means. The patients having a well-defined date of TTV
infection were positive for TTV DNA during a mean period of 3.1 years.
A chronic infection was observed in 31 cases (86%). TTV carriage
appeared clinically benign in all patients. No clinical evidence of a
disease potentially linked to the TTV infection was observed in
patients with TTV DNA carriage over several years. The majority of TTV
carriers had no biochemical evidence of liver disease. The prevalence
of elevated serum alanine aminotransferase (ALT) level was higher in
the TTV DNA-positive group, even in the absence of HCV infection, but
the observed peaks of ALT level were most often transient and very
mild. The prevalence of TTV DNA observed in blood recipients is
consistent with that of TTV infection observed in blood donors. TTV
infection frequently tends to persist. (Blood.
2000;95:347-351)
