[Acute hematogenic interstitial nephritis of urinary origin: an unrecognized factor in the exacerbation of chronic...

Hypertension, phosphate retention, hyperfiltration hyalinosis and the natural course of the underlying are well known factors leading to progression of chronic renal failure. Acute bacterial interstitial nephritis occurring in a previously diseased kidney, although well documented in experimental animals, has not been shown to aggravate chronic renal failure in man. We report on 3 cases of acute suppurative interstitial nephritis, due to E. coli urinary infection complicated by septicemia. All had rapid aggravation of previously mild renal failure secondary to chronic interstitial nephritis. Sepsis originated from the urinary tract which in 2 instances had been temporarily obstructed. Renal biopsy disclosed a diffuse interstitial infiltrate containing numerous polymorphonuclear leukocytes. This was superimposed on chronic tubular and interstitial lesions. In 1 case there were glomerular lesions with crescents and mesangial C3 deposits. A 2nd biopsy performed in 2 cases was of prognostic interest. In one case it showed active lesions and the necessity of continuing the treatment and in the other a satisfactory healing allowing cessation of therapy. Treatment was guided by antibiograms, the clinical and urinary signs of activity, renal biopsy findings and antibiotics known to be concentrated in renal tissue. The duration of treatment seemed important for the regression of acute renal lesions. Hematogenous bacterial interstitial nephritis should be considered as a possible cause of aggravation in chronic renal failure.