Studies on Urine Specimens Adjudged Non-Significant for Bacteriuria

Abstract

The concept of significant bacteriuria continues to form the basis for the diagnosis of urinary tract infections in many laboratories, despite evidence that lower counts of bacteria may be associated with urinary tract infection (UTI). This study investigated the presence of pyuria, leucocyte esterase, nitrite and protein in urine specimens adjudged non-significant for bacteriuria. Methods used included urine centrifugation and microscopy for pyuria, and dip-stick reagent strip testing for leucocyte esterase, nitrites and protein. The presence of significant bacteriuria in the urine specimens was determined on Cysteine lactose electrolyte deficiency (CLED) agar and blood agar using the filter paper method. The cytological and chemical parameters diagnostic of UTI were found in the non-significant bacteriuric specimens as well as in the significant specimens; howbeit at a lower percentage. Similar bacteria were also isolated from both specimen types. Consequently, laboratory diagnosis of UTI on the basis of quantitative criteria should be reviewed since evidence abounds that lower bacterial counts may be observed in symptomatic women.

Keywords: Urinary tract infection, non-significant bacteriuria, pyuria

Journal of Medical Laboratory Sciences Vol. 14 (1) 2005: pp. 48-56