Henoch-Schölein purpura Nephritis (HSPN) and IgA Nephropathy (IgAN) in Children: A Comparison of Pathological Features Using Oxford Classification of IgA Nephropathy.
Xu Zeng. Wayne State University, Detroit, MI
Background: HSPN and IgAN are common in the pediatric population with overlapping clinical, genetic and immunological features causing HSPN to be considered as a systemic form of IgAN. Both entities are characterized by immunofluorescent IgA staining with variable degrees of mesangial proliferation and by IgA deposits on electron microscopy (EM). HSPN has been reported to show more severe glomerular lesions than IgAN however, systemic approach to quantitatively compare both diseases is lacking. The objective of this study was to assess the benefit of applying the newly described semi-quantitative, Oxford classification of IgA nephropathy (OXC-IGA), to distinguishing these two entities.
Design: All consecutive renal biopsy performed at the Children's Hospital of Michigan between 2004-2010 with a diagnosis of IgAN and HSPN were reviewed. The scoring system of OXC-IGA was applied to all biopsies to measure mesangial cellularity (MC, M score), segmental glomerulosclerosis (SG, S score), endocapillary hypercellularity (EC, E score) and tubular atrophy and interstitial fibrosis (TA/IF, T score). In addition, the highest number of MC, percentage of glomeruli with EC, cellular crescent (CC) and segmental necrosis (SN) were also recorded and compared between HSPN and IgAN using student t-test and basing statistical significance of P<0.05.
Results: A total of 23 HSPN (F:M=12:11) and 26 IgAN (F:M=11:15) were diagnosis during the study period. The HSPN patients were significantly younger than IgAN (7.8+/-3.3 vs 12.4+/-3.2, years, p<0.05). Patients with HSPN had significantly higher MC (11 3.2 vs 8.3 2.4), percentage of EC (14.9 2.2 vs 4.9 8.2), CC (10.4 1.2 vs 4.3 2.8) and SN (6.6 1.3 vs 0.7 1.1, all with a P<0.05). There was no significant difference between IgAN and HSPN in M, S, E and T score (p>0.05).
Conclusions: While our data showing IgAN and HSPN to share histopathological features of mesangial/endocapillary proliferation, we demonstrated that HSPN has more extensive mesangial/endcapillary proliferation, high percentage of glomeruli with cellular crescent and segmental necrosis, thus more severe glomerular damage. These findings further characterize pediatric HSPN, therefore benefit to the clinical management.
Category: Kidney (does not include tumors)
Wednesday, March 2, 2011 1:00 PM
Poster Session VI # 248, Wednesday Afternoon