Effective therapy for severe Henoch-Schonlein purpura nephritis with prednisone and azathioprine: A clinical and histopathologic study

Objectives: To validate a scoring system Co assess the severity of renal le sions and to correlate histology with clinical findings. We also examined t he efficacy of treatment with prednisone (1 to 2 mg/kg/d) and azathioprine (1 to 2 mg/kg/d) for severe Henoch-Schonlein purpura (HSP) nephritis. Methods: Twenty patients were evaluated retrospectively. All underwent biop sy before treatment, and 13 underwent biopsy after therapy. We developed a scale based on glomerular, tubulointerstitial (Tl), and vascular changes an d assigned all specimens acuity chronicity, and TI scores. The outcomes of 17 patients were compared with those of a historical control group. Results: Chronicity score at initial biopsy increased with increasing delay between onset of renal involvement and first biopsy (rho = 0.55, P = .016) but did not progress after treatment was initiated. Both acuity (rho = 0.5 7, P = .016) and TI (rho = 0.69, P = .003) scores correlated with clinical severity at first biopsy. The TI score correlated negatively with serum alb umin (rho = -.60, P < .01). Significantly more patients in the study group than in the control group had a favorable outcome (15 [88%] of 17 vs 32 [54 %] of 59, P = .011). Conclusions: Our scale reflects disease activity and highlights the importa nce of TI changes in severe HSP nephritis, Outcome comparisons indicate tha t early treatment with prednisone and azathioprine prevents progression of chronic changes and improves outcome.