Dapsone hypersensitivity syndrome: a clinico-epidemiological review

Diaminodiphenyl sulphone (dapsone) is a drug of choice in the treatment of leprosy. It is also useful for the treatment of many neutrophilic and other dermatoses. Dapsone hypersensitivity syndrome is a rare but well recognized serious adverse effect characterized by fever, skin rashes, generalized lymphadenopathy, hepatitis, and hepato-splenomegaly. Twenty-six patients with dapsone hypersensitivity syndrome were studied for clinical profile, outcome, and prognosis. The male:female ratio was 2.2:1, and the mean age was 33.19 years (range 13 to 64 years). The interval between start of dapsone therapy and appearance of symptoms varied from 2-7 weeks (mean 29.82 days). Twenty-four patients received dapsone as a part of multi-drug therapy for leprosy; the other two patients received dapsone for lichen planus and acne vulgaris. Exfoliative dermatitis was the most common cutaneous manifestation followed by erythematous maculo-papular eruption and Stevens-Johnson syndrome-like lesion. The other common systemic manifestations were: fever (26 cases), itching (22 cases), lymphadenopathy (21 cases), jaundice (21 cases), pallor (20 cases), hepatomegaly (19 cases), and pedal edema (14 cases). Investigation profile revealed elevated levels of serum liver enzymes in 100% of patients, elevated erythrocyte sedimentation rate in 92.3%, raised bilirubin in 84.6%, leucocytosis in 69.23%, low hemoglobin (<9 gm/dl) in 46.15% and hypoproteinemia in 42.3%. Eosinophilia, hemolytic anemia, and reticulocytosis count were found in 4 patients each. All the patients had favorable outcomes except three who died due to hepatic failure. Medical personnel must be aware of this potentially fatal syndrome, because it can cause considerable morbidity and mortality.