Electron-microscopic and immunohistochemical study in Henoch-Schoenlein nephritis.

Henoch-Schoenlein nephritis (HSN) is the most common secondary childhood nephropathy, leading to end-stage renal disease in up to 20% of pediatric patients after long-term follow-up. Forty-four cases of HSN were reviewed (32 children, 12 adults). Electron microscopy (EM) was performed in 7 cases and immunohistochemistry for Ki-67, PCNA, and p27 in all. Light microscopy: grade II (18), III (15), IV (3), and VI (8). Glomerulosclerosis and interstitial fibrosis were important prognostic markers and coexisted with poor outcome. EM was performed mainly in grade VI and was useful in recognition of early glomerulosclerosis. No correlations were found between the Ki67 and PCNA mesangial expression and outcome. Progressive decrease in p27 podocyte expression was noted with more severe HSN grades.