Diagnostic value of dipstick urinalysis as a screening test for urinary tract infection

Choi, Sun Deog; Cho, Han Jun; Kim, Kee Hyuck; Cho, Dong Young; Yu, Byung Yeon

Abstract

BACKGROUND
Urinary tract infection is one of the most common diseases in primary practice. Although quantitative urine culture is the standard for diagnosis, a rapid screening test is needed for effective management. But numerous studies in the past were controversial. We evaluated the utility of dipstick urine analysis as a screening test for urinary tract infection.
METHODS
A retrospective analysis of 311 patients who were admitted between May 1997, and April 1998 were chosen as subjects. Patients had a complete urine analysis, such as microscopic analysis, chemical analysis by dipstick and urine culture was performed as part of an evaluation for urinary tract infection or suspicious febrile illness. We compared dipstick analysis with microscopic examination and urine culture. The results of the dipstick urinalysis were compared with the results of the urine culture, sensitivity, specificity, positive predictive value and negative predictive value.
RESULTS
A total of 311 cases were included in the study among which 122 cases were true positive in urine culture. For dipstick urine analysis 92 of 122 cases were leukocyte esterase positive and 39 of 122 were nitrite positive. On microscopic examination 44 of 122 cases were leukocyte positive and 40 of 122 were microorganism positive.
CONCLUSION
The sensitivity of the dipstick urinalysis seems higher than the microscopic examination in urinary tract infection. We conclude that the dipstick urinalysis is a useful screening test for urinary tract infection for those above 2 years old.