Supplementary Material for: Dapsone-induced granulomatous cholestatic hepatitis unmasked by steroid taper: a case report

Introduction: Dapsone is known to cause drug induced liver injury (DILI) but can rarely induce the formation of hepatic granulomas. In this case, we describe a patient with jaundice who demonstrated granulomas on liver biopsy in response to dapsone. Her symptoms were only evident once steroids, used to also treat her pyoderma gangrenosum, had been tapered. Case: A 67-year-old female was hospitalized due to one day of jaundice. She had started dapsone and prednisone concurrently seven weeks ago to treat her pyoderma gangrenosum. Steroids were discontinued four days prior to symptoms. Her labs were notable for newly elevated alkaline phosphatase (756 U/L), aspartate transaminase (199 U/L), alanine transaminase (273 U/L), and total bilirubin (12.6 mg/dL). Dapsone was held due to suspicion for DILI. A liver biopsy was performed and disclosed non-necrotizing hepatic granulomas. After infectious and autoimmune causes were excluded, dapsone was determined to be the cause of her hepatic granulomas. Her bilirubin and liver enzymes steadily normalized over the next four weeks following discontinuation of dapsone. Conclusion: Dapsone-related liver injury may present following a steroid taper if dapsone and steroids had been initially started together. Hepatic granulomas, though rare, can be seen when dapsone causes DILI.