title: Suppression of tuberculin skin reaction in healthy HTLV-I carriers from Japan.
abstract: Although it is thought that infection with human T-lymphotropic virus type I (HTLV-I) is immunosuppressive, this has not been clearly demonstrated among healthy carriers, and there are no data concerning delayed-type hypersensitivity (DTH). To evaluate this hypothesis, DTH to purified protein derivative (PPD) of tuberculin was measured in 126 healthy adults from an endemic area for HTLV-I infection in southern Japan. Among the 39 HTLV-I carriers, only 15% had detectable induration following PPD exposure, compared to 46% of the 87 non-carriers. In addition, the size of erythema among those carriers with a positive reaction was about 70% of that among non-carriers. Overall, there was a significantly inverse association between the degree of DTH response and prevalence of antibody. In relation to subjects with strong to moderate reaction, those with negative or indefinite reaction were 6 times more likely to be a carrier. This association was much stronger among subjects aged 60 years or older than among younger persons. These findings indicate that there is subclinical immunosuppression among HTLV-I carriers, which increases with age.
authors.affiliation: Second Department of Medicine, Miyazaki Medical School, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Tachibana
authors.forename: A
authors.initials: A
authors.lastname: Okayama
authors.forename: J
authors.initials: J
authors.lastname: Ishizaki
authors.forename: T
authors.initials: T
authors.lastname: Yokota
authors.forename: E
authors.initials: E
authors.lastname: Shishime
authors.forename: K
authors.initials: K
authors.lastname: Murai
authors.forename: S
authors.initials: S
authors.lastname: Shioiri
authors.forename: K
authors.initials: K
authors.lastname: Tsuda
authors.forename: M
authors.initials: M
authors.lastname: Essex
authors.forename: N
authors.initials: N
authors.lastname: Mueller
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D002353:Carrier State / Q000276:immunology*; D005260:Female; D015490:HTLV-I Infections / Q000276:immunology*; D006801:Humans; D006968:Hypersensitivity, Delayed; D007108:Immune Tolerance; D008297:Male; D008875:Middle Aged; D014374:Tuberculin Test