Prevalence of Human T-lymphotropic virus type 1 (HTLV-1) Infection in Patients with Hematologic Disorders and Non-Hematologic Malignancies in a Tertiary Referral Hospital.

BACKGROUND Human T-lymphotropic virus type 1 (HTLV-1) was the first retrovirus identified in human. The current evidence is quite scarce regarding the potential role of HTLV-1 in pathogenesis of hematologic disorders and non-hematologic malignancies. OBJECTIVES The aim of this study is to evaluate the prevalence of HTLV-1 infection in patients with hematologic disorders and non-hematologic malignancies. METHODS This cross-sectional study was conducted on 505 cases of definite diagnosis of hematologic disorders including malignancies as well as non-malignant disorders such as polycythemia and myelofibrosis and non-hematologic malignancies referred to the hematology and medical oncology ward at Army Hospital 501 from January 2015 to January 2016. A 3-mL blood specimen was collected from each patient and tested for the presence of anti-HTLV-1 antibodies using enzyme-linked immunosorbent assay (ELISA). Data were analyzed using SPSS software package version 19 (IBM, New York, USA). Data are presented as mean ± SD if normally distributed and otherwise as median (range). RESULTS Totally, 242 (48%) males and 263 (52%) females with a mean ± SD age of 52.09 ± 16.24 were enrolled in this study. In total, there were 9 (1.78%) cases positive for HTLV-1 infection including 4 males and 5 females. Seven out of 287 (2.4%) patients with hematologic disorders were infected by HTLV-1. In non-hematologic malignancies, 2 out of 211 cases were positive (0.9%). There was no HTLV-1 positive case in 7 patients with both hematologic and non-hematologic disorders. The difference in HTLV-1 infection prevalence between patients with hematologic disorders and non-hematologic malignancies was not statistically significant different (P = 0.31). There was no association between sex and transfusion history with HTLV-1 infection in this population (P = 0.9 and 0.7, respectively). CONCLUSIONS Our study revealed that the prevalence of HTLV-1 in hematologic disorders is higher than the general population. Further larger prospective studies are recommended to corroborate the current evidence.