Experimental Observations on Survival Rates of Erythrocyte and Leukocyte in Urine

Chung, Chung Man; Wang, Chong Soon

Abstract

Quantitative estimation of number of erythrocytes or leukocytes in urine is often used as a clinical guide or a supportive evidence to urogenital tract infections and other urologic diseases (Schreiner, 1957). Occasionally, however, patients with acute urinary tract infection are found to have only small number of white cells in the urine, particularly when the infecting organism is a Proteus strain and small numbers of red cells appeared in hypotonic, alkaline urine specimens due to hemolysis.(9,11,12,14,30,31,32,33) (Rinsler and Gray, 1957; Free et al., 1956; Brumfitt, 1965; Little, 1965; Gnarpe and Edebo, 1965; Cook, 1956; Leonards, 1962; Pryles and Eliot, 1965; Ambrose and Hlil, 1965). It is well known that blood cells in urine may be disintegrated or hemolyzed and these may occur despite refrigeration, particularly in alkaline specimens. In order to investigate these, the survival of blood cells obtained from human blood was examined in vitro under different conditions of specific gravity, pH, temperature of incubation. The erythrocyte and leukocyte suspensions were made by albumin gradient methods (Spriggs and Alexander, 1960). The results obtained are summarized as follows; 1. The rate at which blood cells in urine disappear was found to be accelerated by raising the pH, decreasing the urine S.G., and by increasing the temperature at which suspension were kept.(p<0.01) 2. The most rapid disappearance of blood cells occurred in hypotonic, alkaline medium at 37 C and there was little change in cell suspensions kept in acid (pH; 4.5~5.5) or in hypertonic conditions (S.G.; above 1.024) over a period of 12 hours.(p<0.O1) 3. Under the same conditions of suspending medium, the urinary erythrocytes disappeared more rapidly than urinary leukocytes.(p<0.01)