Objective:
To compare the abilities of two methods for rapid detection of pyuria and three methods of urinalysis to predict significant
bacteriuria in symptomatic ambulatory women.
Design:Prospective simultaneous comparison of the results of dipstick urinalysis, standard microscopic urinalysis, and hemocytometric
cell counting and Gram staining with the results of a standard urine culture.
Setting:Two outpatient ambulatory care facilities serving predominantly minority and uninsured individuals.
Selection criteria:Nonpregnant women presenting with symptoms of urinary tract infection without symptoms of vaginal infection.
Measurements and main results:105 women with symptoms were evaluated. The sensitivities of the dipstick urinalysis and the microscopic urinalysis in predicting
pyuria as defined by hemocytometry were 0.76 and 0.77, respectively, and their specificities were 0.94 and 0.97, respectively.
The sensitivities and specificities of the three methods of urinalysis in predicting ≥10
4
colony-forming units (CFU)/mm
3
in a urine culture were 0.88 and 0.70 for the leukocyte esterase-nitrite dipstick urinalysis, 0.98 and 0.68 for the standard
microscopic urinalysis, and 1.00 and 0.49 for the Gram staining and hemocytometric cell counting.
Conclusions:The standard urinalysis was the most accurate single method to predict significant bacteriuria in symptomatic ambulatory women.
Sequencing the dipstick urinalysis with the standard urinalysis may be a cost-effective approach to evaluating these patients
in clinical practice.
Key words dipstick urinalysis - prediction - urinary tract infection - pyuria - bacteriuria - ambulatory care - women
Received from the Division of Infectious Diseases and the Department of Medicine, University of Colorado Health Sciences Center,
and the Division of Public and Community Health Services, Denver Department of Health and Hospitals, Denver, Colorado.