Human T-lymphotropic virus type I (HTLV-I) is known to be associated with neoplastic and neurodegenerative changes, and it is believed to be associated with various systemic inflammatory diseases, including Sjögren's syndrome (SS). Although HTLV-I infection is endemic in Brazil, there is no information regarding the association between HTLV-I infection and SS in the Brazilian population. The objective of this study was to determine the prevalence of SS in HTLV-I-infected individuals and the prevalence of HTLV-I infection in individuals diagnosed with SS.
Serology for HTLV-I was performed in 50 patients presenting with complaints consistent with SS (the SS group). The HTLV-I group comprised 129 HTLV-I-infected patients who were screened for SS.
None of the patients in the SS group tested positive for HTLV-I. Of the 129 patients in the HTLV-I group, 46 (35.7%) had xerostomia, 18 (13.95%) had xerophthalmia, eight (6.2%) had hyposalivation, two (1.55%) showed impaired tear secretion, and one (0.77%) was positive for autoantibodies (anti-SSB). In addition, six underwent minor salivary gland biopsy, and the histopathological findings were consistent with SS. Only two (1.55%) met the diagnostic criteria for SS.
The prevalence of SS was found to be three times as high in HTLV-I-infected individuals as it was in those without HTLV-I infection. However, given the small number of HTLV-seropositive patients with SS, it is impossible to state that HTLV acts as an immune-activating pathogen for SS.