S-2 : A case of drug reaction with eosinophilia and systemic symptoms syndrome presenting as hepatitis

Introduction: Drug reaction with eosinophilia and systemic symptoms (DRESS) is a rare but severe drug-induced hypersensitivity syndrome, characterized by a maculo-papular rash, fever, eosinophilia, and internal organ involvement. We describe a patient who presented with rash and hepatitis. Case report: A 33-year-old man was referred to our hospital with abnormal results of liver function tests and a rash. He had been taking allopurinol over the previous 3 weeks for treating gout. There was no history of asthma, rash, or any known allergies. On admission, physical examination showed a maculo-papular rash all over the body. Laboratory findings were as follows: white blood cell (WBC) count 104,000/mm3, platelet count 202,000/mm3, eosinophil count 3,914/mm3, alanine transaminase (ALT) level 443 IU/L, aspartate aminotransferase (AST) level 200 IU/L, alkaline phosphatase (ALP) level 137 IU/L, total bilirubin level 0.9 mg/dl, creatinine level 0.9 mg/L, uric acid level 5.3 mg/L, prothrombin time (International Normalized Ratio, INR) 1.5, HBsAg/Ab (-/-), HBc IgM (-), HCV Ab (-), and HAV IgM (-). On day 3 after admission, he had a fever (temperature 39.1℃) and a persistent maculo-papular rash. Laboratory findings were as follows: WBC count 21,270/mm3, platelet count 210,000/mm3, eosinophil count 28,714/mm3, ALT level 341 IU/L, AST level 135 IU/L, total bilirubin level 1.0 mg/dl, and prothrombin time INR, 1.4. Blood cultures were sterile. Abdominal computed tomography showed a normal-sized liver. He was diagnosed with DRESS syndrome. Allopurinol was stopped on the day of admission and high-dose steroid therapy was initiated on day 3 after admission. On day 7 after admission, he was discharged. After 3 weeks, his symptoms were completely resolved and his laboratory findings were within normal limits. Conclusion: Allopurinol is efficacious and safe in most patients, but it is also one of the drugs commonly known to cause DRESS syndrome. Prompt withdrawal of the causative drug and corticosteroid therapy is needed for treating this syndrome. Drug use must be investigated in patients with complaints of rash and abnormal liver function tests to rule out DRESS syndrome.