Immunopathology, extent and course of glomerulonephritis with crescent formation.

Ten out of 66 cases of glomerulonephritis (GN) with variable crescent formation appeared to be of post-streptococcal origin. Immunofluorescent studies of biopsies from 42 of the patients showed findings suggestive of immune complex glomerular injury in 86% whilst there was no evidence of immunologic or nonimmunologic injury in the remainder. Anti-GBM GN was not demonstrable, although it can not be certain that there were no cases amongst the patients whose biopsies were not examined by immunofluorescence. Conservative measures were adequate for the treatment of cases with less than 50% crescents. In the others, with greater than or equal to 50% crescents, appreciable improvement was observed with anticoagulation, immunosuppression and dialysis. The mortality was 30% in cases with 50-80% and 65% in cases with greater than 80% crescents. No appreciable difference in survival was observed between post-streptococcal and idiopathic cases. The single most important factor in prognosis, regardless of etiology, appeared to be the extent of crescent formation. Tubulo-interstitial damage was contributory. Necrotizing angiitis, present in 4 cases, affected the course adversely.