Histopathologic Characteristic of Pediatric Anti-Neutrophil Cytoplasmic Antibody-Associated Glomerulonephritis (ANCA-GN).
Xu Zeng. Wayne State University, Detroit, MI
Background: ANCA-GN is the most common cause of rapidly progressive glomerulonephritis (GN) and the diagnosis is made by renal biopsy. Most ANCA-GN patients are adults. The recently published “histopathologic classification of ANCA-GN” by Annelies et al (J Am Soc Nephrol 21, 2010 e-publish) divides ANCA-GN into four categories (focal, crescentic, mixed and sclerotic ANCA-GN) corresponding to the severity of renal function impairment and outcome. Based on this classification, the majority of adult ANCA-GN belongs to the crescentic group, which has highly active renal disease and severely reduced renal function. There is paucity of reports regarding pediatric ANCA-GN, especialy those corrlating histopathologic changes and outcome. The objective of this study is to charaterize histopathologic changes and outcome in pediatric ANCA-GN.
Design: Renal biopsy cases with a diagnosis of ANCA-GN from pathologic database of Children's Hospital of Michigan between 2004-2009 were reviewed. Based on the predominance of normal glomeruli, cellular crescents and globally sclerotic glomeruli, ANCA-GN case was classified into one of the four categories listed above. In addition, the activity index and chronicity index for each ANCA-GN, including percentage of cellular crescent, segmental necrosis, global sclerotic glomeruli and tubular atrophy and interstitial fibrosis (TA/IF) were recorded.
Results: During the study time frame we identified 7 ANCA-GNs (F:M=4:3). The children ranges from 8-17 year-old (mean age 13.4). Five of 7 cases were focal ANCA-GN (71%) and two were crescentic (29%). None was mixed or sclerotic. Four of 7 ANCA-GN patients carried the diagnosis of Wegener's granulomatosis. The average percentage of crescent, necrosis, global sclerotic and TA/IF was 3.5%, 1.7%, 1.3% and 20, respectively.
Conclusions: The majority of pediatric ANCA-GN have focal disease, and therefore has a favorable renal outcome compared to adult ANCA-GN. The pediatric ANCA-GN has mild activity index including small percentage of cellular crescents and segmental necrosis. The chronicity index is also low in pediatric ANCA-GN with lower number of global sclerotic glomeruli and lower TA/IF.
Category: Kidney (does not include tumors)
Wednesday, March 2, 2011 1:00 PM
Poster Session VI # 251, Wednesday Afternoon