DRESS syndrome: case reportA 69-year-old woman developed DRESS syndrome during treatment with allopurinol for gout. The woman was referred to a hospital by the internal medicine department due to lesions of the oral mucosa. She had history of type 2 diabetes mellitus (for 17 years), hypertension (for 10 years), gout disease and dyslipidaemia. She had surgical history of cholecystectomy and coronary artery bypass surgery. Her medications included metformin, captopril, glibenclamide, isosorbide dinitrate, fluvastatin, propranolol, colchicine and aspirin. Six week prior to the hospitalization, she started receiving allopurinol [dosage and route not stated] for gout flare-up. A week prior to the hospitalization, she developed fever associated with night sweats, chills and malaise. The next day, she noticed labial oedema and bluish spots on her lower limbs.The woman consulted the emergency department, where she received unspecified symptomatic treatment, but with no improvement. Thereafter, she consulted dermatologist, who treated her with prednisolone. Thereafter, she was referred to the internal medicine department, where she was admitted. On day 1 of admission, she was well-oriented and conscious. Tests revealed body temperature of 38.7°C, pulse rate of 67 beats/minute, BP of 120/70mm Hg and body weight of 72kg. Physical examination revealed confluent erythematous maculopapular rash, which was diffused all over the body (stomach, feet, legs, back and chest), sparing the face, palms, scalp and soles. Auscultation revealed that her chest was clear, and heart had regular rhythm and rate. Remainder of the examination showed no abnormalities. At the department of dental medicine, oral examination demonstrated painful erosive cheilitis, confluent ulcerations on the labial mucosa and crusty lesions on the lips. These findings were similar to those observed in some bullous drug eruption, but her Nikolsky sign was negative. She started receiving amoxicillin to prevent infection of the lesions. Prednisolone, chlorhexidine-based mouthwash and unspecified analgesic were prescribed. Oral biopsy was scheduled. Complete blood count demonstrate WBC of 10.28 × 10 3 /mm 3 with lymphocytes of 9.4%, monocytes of 11.3% and eosinophils of 16.1% (1.65 × 10 3 /mm 3 ), indicating moderate eosinophilia. C-reactive protein was elevated (13 mg/L). Findings for tests for serum electrolytes, sedimentation rate, haematocrit and haemoglobin were normal. Serology for hepatitis C and B and blood and urine cultures were negative. Uric acid and serum triglyceride and glucose were high. Skin biopsy showed a subepidermal inflammatory infiltrate comprising of eosinophils and lymphocytes. Histology was consistent with a toxic drug reaction. Based on her history, biological tests and clinical presentation, she was diagnosed with cutaneous adverse drug reaction. She started receiving treatment with prednisolone. The most likely cause of reaction was thought to be the allergic response to allopurinol. On day 7of admission, alteration in renal function was o...