A CASE OF THE DAPSONE SYNDROME

The 'dapsone syndrome' developed in a 44-year-old woman who was treate d for pyoderma gangrenosum with 100 mg/day dapsone for about 5 weeks. Symptoms included fever, malaise, jaundice with hepatic dysfunction, l ymphadenopathy, mononucleosis and dermatitis. These symptoms disappear ed with 30 mg/day of oral prednisolone. A lymphocyte stimulation test with dapsone was positive, as was the delayed-type intradermal skin te st with 0.5 and 0-05% dapsone in saline. Immunohistochemical studies o f the rash and skin test reaction revealed that the dominant infiltrat ing T cells in the upper dermis were of the Leu 2a+ cytotoxic/suppress or-type rather than the Leu 3a+ helper/delayed hypersensitivity-type.