Sulfonamide-reactive lymphocytes detected at very low frequency in the peripheral blood of patients with drug-induced eruptions.
BACKGROUND
The role of T lymphocytes in mediating drug eruptions is uncertain.


METHODS
Twenty-four patients with eruptions induced by sulfonamide-related drugs were studied to detect lymphocyte reactivity to drugs. Both the lymphocyte transformation test and limiting dilution analysis were used as assays for drug-reactive lymphocytes. Peripheral blood lymphocytes were expanded in interleukin-2 and tested for reactivity to sulfamethoxazole and furosemide.


RESULTS
The lymphocyte transformation test results to sulfamethoxazole, sulfisoxazole, and furosemide were found to be generally unreliable with a high rate of false-negative and false-positive results. However, as determined by limiting dilution analysis, sulfamethoxazole-reactive lymphocytes were detected in the peripheral blood of one patient at a frequency of 1/172,000. This is within the lower range of frequencies of urushiol-reactive T cells in the peripheral blood of patients with allergic contact dermatitis to urushiol (poison ivy). Two sulfonamide-reactive lymphocyte lines were cultured from two patients. Both lines proliferated in response to sulfamethoxazole but not in response to furosemide, suggesting that furosemide does not cross-react with the sulfonamides.


CONCLUSIONS
Lymphocytes reactive to sulfamethoxazole were detected at low frequencies in the peripheral blood of three patients with drug eruptions secondary to administration of sulfamethoxazole.
Kalish
R S
RS
Department of Dermatology, State University of New York at Stony Brook, 11794-8165.
LaPorte
A
A
Wood
J A
JA
Johnson
K L
KL
D000328:Adult; D000368:Aged; D002478:Cells, Cultured; D003875:Drug Eruptions / Q000097:blood* / Q000209:etiology; D005260:Female; D005665:Furosemide / Q000009:adverse effects*; D006801:Humans; D008213:Lymphocyte Activation / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D013444:Sulfisoxazole / Q000009:adverse effects*; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D015662:Trimethoprim, Sulfamethoxazole Drug Combination / Q000009:adverse effects*
D013444:Sulfisoxazole; D005665:Furosemide; D015662:Trimethoprim, Sulfamethoxazole Drug Combination