[Phagocytic activity of monocytes in human primary glomerulonephritis].

Circulating immune complexes (CIC) account for a majority of GN. Their pathogenicity depends on size, molecular composition, glomerular hemodynamics and activity of phagocytes. The phagocytic function of peripheral monocytes was studied in 23 patients with nonsystemic GN. Phagocytic activity of peripheral blood monocytes was assessed in vitro, by calculating phagocytic index (IP: number of zymozan particles in each monocyte) and phagocytosis percentage (PP: number of phagocyting monocytes); the tests were carried out on autologous and heterologous serum samples. In 13 controls, PP was 79 +/- 5.8%. In 7 membranous GN, 6 membranoproliferative GN and 10 lipoid nephrosis, PP was severely decreased, 63.4 +/- 9.6%, 52.1 +/- 19% and 52.2 +/- 14%. In each group of GN, these results were significantly different from controls (p less than 0.01). In all groups these results were similar in autologous and heterologous serum samples (55 +/- 13% and 57.5 +/- 16%; NS). Therefore, this defect was not linked to the presence of serum inhibitors. In conclusion, alterations of phagocytic activity is present in some primary GN and may explain an insufficient rate of CIC removal.