Differential count of urinary leucocytes and renal epithelial cells by phase contrast microscopy

A total of 291 urine sediments from 255 patients with various renal or urinary tract diseases have been studied by phase contrast microscopy. Based upon morphological criteria, leucocytes were distinguished from renal epithelial cells and the white blood cells were classified either as mononuclear or polynuclear in 179 patients. The percentage of the different cell types varied considerably between and within the different diseases. The median values for polynuclear granulocytes were higher than 90% in bacterial renal or urinary tract disease and in polycystic kidney disease. In interstitial nephritis, nephrosclerosis and in renal transplanted patients the percentage of polynuclear granulocytes was somewhat lower, 76-85%. In diabetes, amyloidosis, tubular nephrosis (necrosis) glomerulonephritis, lupus nephritis and endemic benign nephropathy there were 14-66% polynuclear granulocytes. 29-33% mononuclear leucocytes were found in lupus nephritis and endemic benign nephropathy. The greatest proportion of renal epithelial cells was found in endemic benign nephropathy, namely 49%. 36% renal epithelial cells were found in tubular nephrosis (necrosis) and in glomerulonephritis. The technique is rapid and inexpensive. It facilitates differential diagnostics of urinary tract disease with pyuria.