Antibiotic-induced recurring interstitial nephritis.

Acute interstitial nephritis (AIN) is often induced by drug therapy and accounts for 1%-3% of adult cases of renal failure. A 13-year-old white female with cystic fibrosis developed two episodes of biopsy proven AIN following antibiotic use over a 5-year period. The first episode resolved with pulse steroid therapy and the second resolved without intervention. Steroid therapy may play a role in aborting subsequent AIN attacks.