High seroprevalence of anti-HTLV-I antibody in rheumatoid arthritis.
OBJECTIVE
To investigate the association between human T lymphotropic virus type I (HTLV-I) infection and rheumatoid arthritis (RA) in Nagasaki, an area highly endemic for HTLV-I infection.


METHODS
Sera from 113 female patients with RA and 19,796 female blood donors were screened for anti-HTLV-I antibodies with a gelatin particle agglutination kit and confirmed using an immunoblotting kits.


RESULTS
The age-adjusted summary odds ratio of HTLV-I infection among RA patients, as compared with blood donors, was 2.8 (95% confidence interval [95% CI] 1.8-4.6). The etiologic fraction, i.e., the proportion of RA in the study population that is attributable to HTLV-I infection, was estimated to be 13.2% (95% CI 5.1-21.2). There was no significant difference in the clinical and laboratory findings between HTLV-I- infected and HTLV-I-uninfected RA patients.


CONCLUSIONS
These epidemiologic findings support the idea that HTLV-I infection is a risk factor for RA, and suggest that approximately 13 % of the cases of RA in females living in Nagasaki are associated with HTLV-I infection.
Eguchi
K
K
Nagasaki University School of Medicine, Japan.
Origuchi
T
T
Takashima
H
H
Iwata
K
K
Katamine
S
S
Nagataki
S
S
D000328:Adult; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000000981:diagnostic imaging / Q000276:immunology*; D005260:Female; D015528:HIV Seroprevalence; D015481:HTLV-I Antibodies / Q000097:blood*; D006801:Humans; D007564:Japan / Q000453:epidemiology; D007592:Joint Diseases / Q000000981:diagnostic imaging / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011859:Radiography; D017678:Sex Distribution
D015481:HTLV-I Antibodies