Allopurinol-induced drug reaction with eosinophilia and systemic symptoms syndrome in a patient with previous nephrectomy: a case report.

backgroundDrug reaction with eosinophilia and systemic symptoms is a rare but serious hypersensitivity reaction, typically occurring 2-8 weeks after drug initiation. It presents with rash, fever, hematological abnormalities, and multi-organ involvement, most commonly affecting the liver, kidneys, and lungs. Allopurinol is a well-recognized trigger, particularly in patients with renal impairment. This case is notable owing to the patients' previous donor nephrectomy, rather than intrinsic renal disease. CASE PRESENTATION: A 76-year-old white British male with a history of donor nephrectomy and stable renal function (baseline estimated glomerular filtration rate 50 mL/minute/1.73 m

conclusionThis case highlights the importance of a clear medication history when assessing a patient with cutaneous and systemic symptoms. It highlights that drug reaction with eosinophilia and systemic symptoms is a rare, but an important differential to consider, particularly in patients with underlying kidney dysfunction, even in those without intrinsic kidney disease.