Immunofluorescent study of urine sediments was performed to detect glomerular epithelial cell injuries using specific monoclonal antibody against podocalyxin, a glycoprotein that is prominently expressed on glomerular epithelial cells. Three kinds of structures (casts, granules and cells) were stained in urine sediments from various glomerular diseases. The presence of podocalyxin in urines was confirmed by absorption test, immunoelectron microscopy and Western blotting. Podocalyxin was detected in the urinary sediments of patients with various forms of glomerulonephritis, particularly those with acute onset. The amount of their urinary excretion apparently indicates the degree of the glomerular epithelial cell injuries in glomerular diseases.