Background: The purpose of this study was to discover ways to screen urine culture specimens through Gram stains, urine stick analyses and microscopic examinations for the laboratory cost saving.

Methods: One hundred and fifty-eight urine specimens for culture were included. Fifty uL of urine were inoculated onto one well each of 10-well slide, dried on the hot plate, and Gram-stained. The results combined with routine urinalyses including urine nitrite and leukocyte esterase, and pyuria, were compared with the routine culture results.

Results: The screening of bacteriuria by Gram stains, urinalyses and microscopic examinations revealed the high sensitivity (91.9%) and negative predictive value (95.5%) with cost saving of 41.8% of inoculating media. Not considering the Gram stains, the screening revealed 83.8% sensitivity and 92.5% negative predictive value, even if the cost saving of inoculating media were as high as 50.1%.

Conclusion: It was demonstrated that it was sensitive and economic and produced rapid preliminary results to screen bacteriuria by the Gram stains combined with urinalyses and microscopic examinations. (Korean J Clin Microbiol 2000;3(1):53-56)