title: Study of the Associations Between TT Virus Single and Mixed Infections With Leukemia.
abstract: BACKGROUND
  The pathogenic association of Transfusion Transmitted Virus or Torque teno Virus (TT Virus) single and mixed infections with leukemia was under evaluation in these years but confront with controversies. This hypothesis is based on the higher prevalence of TT Virus infection in patients with leukemia compared with controls.
  
  
  OBJECTIVE
  The aim of this study was to determine the frequency of TT Virus, Cytomegalovirus (CMV), Hepatitis B Virus (HBV), and Hepatitis C Virus (HCV) infections in patients with leukemia and healthy controls.
  
  
  METHODS
  In this cross sectional study, 95 patients with leukemia and 100 healthy controls who were admitted to the Namazi Hospital affiliated to the Shiraz University of Medical Sciences, Shiraz, Iran, were enrolled between years 2012 and 2013. Blood samples treated with EDTA were collected from each patient with leukemia and controls. The existence of TT Virus infection was analyzed using the semi-nested PCR method. The immunological prevalence of HBV and HCV infections were evaluated using HBs-Ag and HCV-Ab ELISA based protocols, respectively. Active CMV infection was also evaluated using an immunofluorescence method. Also risk factors of leukemia and viral infections were statistically analyzed in patients with leukemia.
  
  
  RESULTS
  The TT Virus infection was significantly found in 40 of 95 (42.1%) and 12 of 100 (12%) patients with leukemia and controls, respectively. The HBs-Ag and HCV-Ab were detected in 27 of 95 (28.4%) and 18 of 69 (26.1%) patients with leukemia but were not found in the controls. Active CMV infection was also found in 11 of 69 (16%) patients and none of the controls. Significant co-infection of TT Virus was found with HBV (15 of 40; 37.5%), HCV (14 of 40; 35%) and CMV (7 of 40; 17.5%) in patients with leukemia.
  
  
  CONCLUSIONS
  Confirmation of the significantly higher frequency of TT Virus, HBV, HCV and CMV single infection and their co-infection in patients with leukemia compared with healthy controls, emphasizes the determinative role of TT Virus pathogenesis in clinical outcomes observed in patients with leukemia, which requires extensive evaluation by further studies.
authors.affiliation: Department of Biology, Arsanjan Branch, Islamic Azad University, Arsanjan, IR Iran.
authors.forename: Marjan
authors.initials: M
authors.lastname: Shaheli
authors.affiliation: Shiraz Transplant Research Center, Shiraz University of Medical Sciences, Shiraz, IR Iran.
authors.forename: Ramin
authors.initials: R
authors.lastname: Yaghobi
authors.affiliation: Department of Microbiology, Jahrom Branch, Islamic Azad University, Jahrom, IR Iran.
authors.forename: Abbasali
authors.initials: A
authors.lastname: Rezaeian
authors.affiliation: Department of Biology, Arsanjan Branch, Islamic Azad University, Arsanjan, IR Iran.
authors.forename: Mahdiyar
authors.initials: M
authors.lastname: Iravani Saadi
authors.affiliation: Hematology Research Center and Bone Marrow Transplant Unit, Shiraz University of Medical Sciences, Shiraz, IR Iran.
authors.forename: Mani
authors.initials: M
authors.lastname: Ramzi
keywords: Cytomegalovirus; Hepatitis B Virus; Hepatitis C Virus; Torque teno Virus