Drug-induced interstitial nephritis. Coexistence with glomerular disease

Drug-induced interstitial nephritis is being recognized with increasing frequency. Pharmacologic agents responsible for inducing this entity include antibiotics, diuretics, and nonsteroidal anti-inflammatory drugs. We recently examined five patients with glomerular disease and drug-induced interstitial nephritis. In three patients prior biopsy specimens documented their glomerular disease (membranous nephropathy, crescentic glomerulonephritis, and presumptive lipoid nephrosis). A second biopsy specimen showed acute interstitial nephritis and the glomerular lesion. Two additional patients had single biopsy specimens demonstrating acute interstitial nephritis and either membranous nephropathy or crescentic glomerulonephritis. Our cases emphasize the need for recognizing this complex pattern of renal disease and the difficulties encountered in rendering a proper diagnosis.