Our study examines the relationship between in vivo delayed type hypersensitivity (DTH) and clinical and laboratory variables associated with rheumatoid arthritis (RA). Eleven patients with RA were examined. They were receiving no disease modifying drugs, immunosuppressive agents or corticosteroids. Skin tests were performed with the Multitest CMI system employing 7 antigens simultaneously. No patients were truly anergic, however, 3 of the 11 patients were hyporesponsive. No difference was noted between the total in vivo DTH responses of the patient and control populations. A significant correlation was observed between total DTH and the overall activity of the RA as measured by the erythrocyte sedimentation rate (ESR). However, there was no relationship between the total DTH scores and the degree of synovitis. There was no correlation between DTH and a variety of laboratory variables including the autologous mixed lymphocyte response, and the percentage of activated CD4+ or CD8+ T lymphocytes. These observations indicate that while anergy was uncommon in our population of patients with RA, decreased DTH responses were associated with greater disease activity as determined by the ESR.