Clinical usefulness of CD68 staining in children with various glomerular diseases

PURPOSE: Glomerular macrophage accumulation is a common feature of proliferative forms of human glomerulonephritis and kidney injury. Our present study was designed to investigate the role of macrophages in pediatric kidney diseases by using CD68 staining. MATERIAL AND METHODS: Seventy-four patients (39 boys and 35 girls) with pediatric kidney disease yielding 81 specimens were investigated. A monoclonal anti-human CD68 mouse antibody (KP1) was used as a macrophage marker in this study. Paraffin-embedded renal biopsy specimens were stained for immunohistochemical analysis. The average number of macrophages per glomerulus in each patient was calculated as the total number of CD68 (+) cells within all glomeruli divided by the total number of glomeruli in a single section and the average number of observed interstitial macrophages was calculated in 3-5 high power fields. RESULTS: Glomerular macrophage accumulations were increased with crescentic proliferative glomerulonephritis, mesangial proliferative glomerulonephritis, and focal segmental glomerulosclerosis. Glomerular and interstitial macrophage accumulations were correlated with hematuria, proteinuria and renal function (eGFR). In particular, activity and chronicity index, as well as the severity of glomerular IgA, C3, and fibrinogen deposition were correlated with glomerular macrophage accumulation. CONCLUSIONS: Macrophage accumulation observed by CD68 staining was a useful marker in providing a deeper understanding of the clinicopathologic state of children with chronic kidney diseases, and was effective in the selection of treatment.