Acute interstitial nephritis due to deferasirox: a case report.

Deferasirox is a new oral iron chelator used to treat transfusional iron overload. Pre-marketing clinical trials revealed little organ-specific toxicity. Increases in serum creatinine were noted in one-third of patients but were mild and non-progressive. We describe a 62-year-old man with myelodysplastic syndrome who developed a progressive decline in renal function after starting deferasirox. A kidney biopsy showed acute interstitial nephritis with increased eosinophils, suggesting drug hypersensitivity. Deferasirox was discontinued and renal function returned to baseline. This is the first pathological description of deferasirox-related acute kidney injury in humans, which differs from tubular vacuolization observed in animals.