Correlates of hematuria on glomerular histology and electron microscopy in IgA nephropathy.

BACKGROUND: Hematuria is the most important clinical manifestation of IgA nephropathy. This study was undertaken with the objective to describe the spectrum of histological changes with reference to the Oxford classification and the ultrastructural changes in the glomerular basement membrane and to correlate them with hematuria.

METHODS: 66 patients who underwent renal biopsy for IgA nephropathy were evaluated histologically by the Oxford system and also subject to electron microscopic examination for glomerular immune deposits, as well as alterations in the glomerular basement membrane.

RESULTS: On comparing the histological scores generated by the Oxford classification with degree of hematuria, it was found that the status of 'endocapillary proliferation' and the status of 'tubular atrophy and interstitial fibrosis showed a significant correlation. Correlation of hematuria with location of the deposits, i.e. mesangial only, and mesangial with capillary wall deposits (subendothelial and subepithelial) did not show any association. Other alterations of the GBM were seen in 12 cases. The changes included thinning alone in 4 cases, thinning and lamellar splitting in 5 cases, and lamellar splitting alone in 2 cases.

CONCLUSION: At presentation, endocapillary proliferation is one histological parameter which shows close association with hematuria.