Evaluation of clinical and histological prognostic markers in drug-induced acute interstitial nephritis.

We analyzed the case records of 19 patients diagnosed to have drug-induced acute interstitial nephritis to assess the clinical profile and role of steroids in renal recovery, and to correlate histological features to outcome. Patients with underlying glomerular diseases, malignancy, obstructive nephropathy, or systemic infections were excluded. Nonsteroidal anti-inflammatory drugs alone accounted for 6 cases (group A), whereas antibiotics were the major offender in the remaining patients (group B). In 13/19 (69%) cases, renal failure was severe enough to require dialytic support. Overall 14/19 (74%) of the patients recovered normal renal function within 6 weeks of withdrawal of the offending drugs. Neither the extent of renal recovery nor the time required for it was altered by oral steroids. Tubular atrophy and interstitial fibrosis adversely affected renal recovery. Oliguria, tubular necrosis, interstitial edema, and the density/distribution of interstitial infiltrate did not have any effect on the rate/extent of renal recovery.