Dapsone Syndrome

Abstract

Introduction: Dapsone syndrome is a distinct hypersensitivity reaction characterized by skin rash, fever, generalized lymphadenopathy, hepatosplenomegaly and hepatitis which subside with cessation of dapsone therapy. Case Report: A 37 year old male on dapsone lOO mg twice daily for erythema elevatum diutinum (a cutaneous vasculitis) presented with fever, icterus, skin rash and hepatosplenomegaly at five weeks. Investigations revealed the following: Hb 9.8 g%, serum bilirubin 9.0 mg%, SGOT 600 IZJ/l and SGPT 650 IU/l. Peripheral blood smear showed haemolytic anemia; bone marrow biopsy revealed erythroid hyperplasia. ICT for falciparum malaria, DGI for leptospira, Weil-Felix test, HBsAg and HIV were negative. A diagnosis of Dapsone Syndrome was made. Dapsone was stopped and prednisolone started in a low dose. The patient recovered completely and was discharged after 03 weeks. Discussion: Dapsone syndrome is also called “five week dermatitis” because it commonly occurs during the fifth week dapsone intake. Although the exact cause of dapsone syndrome is unknown, preferential metabolism by the N-hydroxylation pathway is considered key to its pathogenesis. Using Naranjo’s ADR probability scale we inferred that dapsone intake was the probable cause in this case (score of 6). In view of its increasing incidence, practitioners prescribing dapsone need to be familiar with the syndrome.

Keywords

• Dapsone
• Cutaneous Vasculitis