Prognostic Value of Berden Histopathological Classification in Anca-Associated Vasculitis with Renal Involvement: A Single-Center Retrospective Cohort Study

The kidneys are frequently affected by anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides, and this renal involvement is a significant determinant of the disease's prognosis. Certain demographic, laboratory, and histopathological findings are effective in predicting kidney and patient survival. The objective of this research was to evaluate both the prognostic utility of the Berden histopathological classification and the determinants of survival among patients with ANCA-associated vasculitis (AAV) and concurrent renal involvement, who were diagnosed at Bursa Uludağ University Hospital. This retrospective analysis comprised 47 cases of AAV identified from a cohort of 1954 patients who underwent renal biopsy at our institution between 1987 and 2017. The demographic, histopathological, and laboratory findings of the patients were examined. Glomerular findings in renal biopsies were evaluated to classify the histopathology and calculate the percentage of normal glomeruli. The prognostic value of these parameters for predicting first-year treatment responses (remission, end-stage renal disease, and death) was evaluated. Histopathological classification, the percentage of normal glomeruli, baseline creatinine, eGFR, proteinuria, and C-reactive protein (CRP) levels were all identified as significant predictors of first-year treatment response (p = 0.046, p = 0.004, p = 0.026, p = 0.021, p = 0.039, and p = 0.016, respectively). While the focal group showed the best prognosis, the sclerotic group had the worst. Factors associated with a poor prognosis included a low normal glomerular percentage in the kidney biopsy, low baseline eGFR, and high levels of baseline serum creatinine, CRP, and proteinuria. Histopathological biopsy findings, histopathological classification model, and certain laboratory markers are effective predictors of treatment response and prognosis in ANCA-associated glomerulonephritis.