Dapsone Hypersensitivity Syndrome-related Lung Injury without Eosinophilia in the Bronchoalveolar Lavage Fluid

A 73-year-old man was admitted in respiratory failure that had subacutely progressed after five weeks of dapsone treatment for a skin rash. He also presented with fever, systemic erythroderma and liver dysfunction. Chest computed tomography showed diffuse reticular shadows with ground-glass opacity and bilateral mediastinal lymphadenopathy. Lymphocytes, but not eosinophils, were increased in the bronchoalveolar lavage fluid. Moreover, reactivation of human herpes virus-6 was confirmed on a paired serum test. Finally, we diagnosed the patient with dapsone hypersensitivity syndrome (DHS), a rare adverse event of this drug. Lung injury unaccompanied by eosinophilia in the bronchoalveolar lavage fluid is even more rare as a DHS-related lung manifestation.