Purified protein derivative reaction in systemic lupus erythematosus patients. Indirect study of cellular immunity.

Cutaneous anergy in SLE patients results from disease activity and/or immunosuppressive treatment (IT). The aim of this study was to evaluate purified protein derivative (PPD) reaction in SLE patients. A total of 145 patients and 20 controls were studied. Five units of PPD were applied on day 0, and skin reaction was measured after 3 (PPD1) and 6 (PPD2) days. A booster was applied (day 14), and the reaction was measured after 3 (PPD3) and 6 (PPD4) days.Non-parametricANOVA test and unpaired Student's t-test were performed. Forty patients (group I) were inactive (MexSLEDAI 3), receiving no IT (at least 3 months previous to the PPD test); 39 (group II) were inactive receiving IT; 24 (group III) were active without IT, and 42 (group IV) were active with IT. Active patients had lower PPD1 (group III, 1.4 ± 0.9; group IV, 0.6 ± 0.5) than inactive patients (group I, 8.4 ± 2.3; group II, 5.1 ± 1.9) and than controls (9.4 ± 3; P ≤ 0.001). Group IV had lower delayed response (PPD2 = 0.3 ± 0.3) than inactive groups ...