Summary

• Caused by acute inflammation of the renal interstitium, most likely mediated by a hypersensitivity reaction.
• Usually triggered by an offending medication, of which >100 are known. Also occurs in chronic inflammatory disease.
• Presents with acute renal failure and the "hypersensitivity triad" of rash, fever, and eosinophilia. Nephrotic syndrome may also be present in cases triggered by non-steroidal anti-inflammatory drugs.
• Usually resolves once the offending medication is discontinued.
• Treatment is largely supportive, with management of fluid electrolyte balance and fluid retention. Corticosteroid therapy may be given to increase the rate and extent of renal functional recovery.
• Prognosis is good, although most patients have some residual renal impairment.