Clinical significance of TT virus infection in patients with chronic liver disease and volunteer blood donors in Egypt

Abstract

Clinical significance of TT virus (TTV) infection was investigated in Egyptian patients with chronic liver disease and volunteer blood donors by a cross sectional analysis. TTV DNA in serum was assessed by a semi-nested polymerase chain reaction. The prevalence of TTV DNA did not differ among patients with chronic hepatitis B (11/24, 46%), chronic hepatitis C (22/72, 31%), or schistosomal liver disease (14/39, 36%). No difference in prevalence was found between blood donors (32/109, 29%) and each of the patient groups. Clinical background including mean age, sex distribution, history of blood transfusion, and mean level of alanine aminotransferase did not differ between TTV DNA-positive and -negative individuals in any of the study groups. Ultrasonographic evidence of liver cirrhosis was similar between TTV-positive and -negative patients in each of the chronic liver disease groups. TTV infection was not associated with hepatitis B or C virus infection in blood donors. The only significant difference observed was the lower concentration of serum HCV RNA in TTV DNA positive compared with negative patients with chronic hepatitis C (3.0 +/- 1.4 vs. 4.0 +/- 0.9 log copies/ml, P <. 001). In conclusion, TTV infection was not associated with either past history of blood exposure or infection with bloodborne hepatitis viruses in Egypt. No clinical significance of TTV was found in the present study. However, a reciprocal interaction was suggested between TTV and HCV replication.

Factors predisposing to the occurrence of cryoglobulinemia in two cohorts of Egyptian and Japanese patients with chronic hepatitis C infection: Ethnic and genotypic influence

“…This study included 50 of 72 Egyptian patients with chronic hepatitis C, who had participated previously in a study of TTV infection in Egyptians [Gad et al, 2000]. All were infected with HCV genotype 4, and all met the selection criteria of being noncirrhotic, with no associated autoimmune, schistosomal, alcoholic, or malignant liver disease, and having no other autoimmune or serious systemic disease according to our working definition.…”

High prevalence of TT virus‐related DNA (90%) and diverse viral genotypes in norwegian blood donors

“…The virus appears to replicate in liver and was assumed initially to be associated with liver dysfunction [Okamoto et al, 1998a]. While some investigators ®nd evidence for liver damage associated with TTV infection [Okamoto et al, 1998b;Tanaka et al, 1998;1999 Q1 ;Cleavinger et al, 2000], others do not [Yuki et al, 1999;Gad et al, 2000;Kao et al, 2000;Sugiyama et al, 2000].…”

Molecular Epidemiology and Clinical Implications of TT Virus (TTV) Infection in Indian Subjects

“…26 Among the Asian countries, Japan (28%-62%), 20,32 Myanmar (96%), 16 and Singapore (98%) 5 have relatively higher prevalences as compared with Taiwan (23.4%), 33 Thailand (36%), 34 and Pakistan (16%). 7 Similarly, the prevalences in Africa (29%-86%) 7,35 *These were subjects who had undergone some invasive, investigative procedure or were transfused with more than 5 units of blood or blood products.…”