Delayed hypersensitivity skin testing to mumps and Candida albicans antigens is normal in middle-aged HTLV-I- and-II-infected U.S. cohorts.

It has been reported that human T cell lymphotropic virus (HTLV)-I-infected persons in Japan have decreased delayed hypersensitivity skin test reactivity to tuberculin purified protein derivative (PPD), but HTLV-I- or -II-infected persons do not generally develop opportunistic infections. We administered standardized intradermal testing with PPD, mumps, and Candida albicans antigens to 31 HTLV-I, 48 HTLV-II, and 143 seronegative subjects in the United States. Reactivity at 48 hr was compared among the three groups. Response rates to PPD were very low in all subjects. Fifty-five percent of seronegative subjects did not react to mumps antigen, compared with 55% of HTLV-I [adjusted odds ratio (OR) = 0.79, 95% confidence interval (CI) 0.27-2.33] and 38% of HTLV-II (OR = 0.73, 95% CI 0.33-1.64). Fifty-one percent of seronegatives did not react to Candida albicans antigen, compared with 34% of HTLV-I (OR = 0.37, 95% CI 0.15-0.93) and 46% of HTLV-II (OR = 0.71, 95% CI 0.34-1.52). Anergy was present in 33% of seronegatives, 28% of HTLV-I (OR = 0.60, 95% CI 0.20-1.78), and 19% of HTLV-II (OR = 0.56, 95% CI 0.22-1.44). HTLV-I- and -II-infected persons appear to have intact delayed hypersensitivity skin test responses to mumps and Candida albicans antigens.