Validation of a newly proposed histopathological classification in Japanese patients with anti-neutrophil cytoplasmic antibody-associated glomerulonephritis

摘要

Background A new histopathological classification of anti-neutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis was recently proposed. We evaluated the predictive value of this classification for renal outcome in Japanese patients. Methods We enrolled 122 patients with ANCA-associated glomerulonephritis diagnosed at several institutions in Japan between January 2000 and March 2010. Twenty patients were excluded because of observation durations of Results The study population included 54 men and 48 women. Age, estimated glomerular filtration rate (eGFR), and proteinuria were 66.3?±?11.3?years, 21.6?ml/min. and 1.10?g/24?h, respectively. Eighty-six patients were positive for myeloperoxidase-ANCA, five were positive for proteinase 3-ANCA, and 11 were negative for both antibodies. Median follow-up time was 41.0?months. Twenty-three patients (22.5%) developed ESRD during the follow-up period. Twelve patients died during follow up; 7/12 patients developed ESRD before death, and 5/12 patients died without ESRD. The incidence of ESRD increased with sequential categories: focal, 2/46 (4.3%); crescentic, 9/32 (28%); mixed, 8/18 (44%); and sclerotic, 4/6 (67%). The focal class had the best renal survival and the sclerotic class had the worst renal survival (p?p?=?0.1074). Conclusion The new histopathological classification was associated with eGFR at 1?year and tended to be associated with ESRD in our Japanese cohort with ANCA-associated glomerulonephritis. α-SMA positivity might be an additional prognostic factor for ESRD.