Abstract: A 28-year-old man was admitted to our hospital due to fever for four weeks and erythema and scales on all his skin for three weeks in August, 2004. The patient developed psoriasis vulgaris nine weeks ago and was treated with tripterygium wilfordii, dapsone, roxithromycin and compound ammonium glycyrrhizinate. He began fever four weeks ago and had erythema on trunk and extremities, elevated transaminase and lymphadenopathy three weeks ago. He was given glucocorticoid and antibiotic therapy by other hospitals. But his lesions gradually became severe. Physical examination revealed his temperature was 37.7℃ and several lymph nodes in his neck, axillary and groin were found with skin erythema and scales all around his body. Laboratory tests showed increased alanine aminotransferase (ALT,384 U/L), aspartate aminotransferase (AST,152 U/L), total bilirubin (TBIL, 140.2 μmol/L), direct bilirubin (DBIL, 107.7 μmol/L) and decreased albumin albumin (ALB,31.2 g/L). The patient was diagnosed with erythrodermic drug eruption and drug induced hepatitis. Then dapsone and other agents were ceased. After 47 days of treatment with glucocorticoid and extra-nutrition, the patient was cured and discharged. His was found carrying HLA-B*13:01 allele 13 years later during follow up. The IL-5 enzyme-linked immunospot assay on his peripheral blood mononuclear cells stimulated by dapsone in vitro was positive. Finally, the diagnosis of dapsone hypersensitivity syndrome was made.

Key words: dapsone, HLA-B*13:01 allele, drug hypersensitivity syndrome