How Sensitive Is Urine Dipstick Analysis in Predicting Urinary Tract Infections in Symptomatic Adults in a Primary Care Setting ?

Abstract

Background: Urinary tract infection (UTI) is a common clinical problem in the primary care setting. Urine dipstick analysis is a quick, cheap and widely used test to predict UTI in clinically suspected patients. Objective: To evaluate the sensitivity of urine dipstick analysis as a screening test in predicting UTI in symptomatic adults in the primary care setting. Methods: A total of 420 culture-positive urine samples from patients with symptomatic UTI, who had dipstick urinalysis in a primary care center were the materials of this study from March to October 2015. The sensitivity of urine dipstick nitrites (NT), leukocyte esterase (LE) and blood was calculated and compared with positive culture samples either individually or in combination. Results: The sensitivity of dipstick NT alone was the lowest of all tests (20.7%), while LE alone was marginally higher than NT (31.42%), whereas dipstick blood test when considered alone was the highest sensitive (61.9%). In combination, NT and/ or LE were marginally higher than either test alone (41.2%), while NT and/or blood were (64.5%). The highest sensitivity of dipstick is obtained when all the three parameters were considered together (NT and/or LE and/or Blood, sensitivity 81.4%). Conclusion: Dipstick NT, LE, and blood are poor screening tests when used individually. Dipstick sensitivity significantly increases, and it could be considered a good screening test to predict UTI in symptomatic adults in the primary care setting when its three components are considered together. However, negative dipstick analysis should not rule out UTI in symptomatic adults, and urine culture is necessary for accurate diagnosis.