Urine Flow Cytometry in the Diagnosis of Urinary Tract Infection
To determine the cut-off value of bacteria with urine flow cytometer in diagnosing urinary tract infection.
From a total of 546 patients admitted to the hospital with urinary tract infection (UTI), two urine samples were obtained for each patient. Urine samples in sterile containers were divided into two; first for urine culture and second for simultaneous measurement with UF-1000i flow cytometry device. The presence of a single type of bacteria over 103 CFU/mL in urine culture was accepted as UTI.
Of 546 patients, 210 (38.5%) were boys and 336 (61.5%) were girls. There was no growth in 489 (89.5%) of the urine specimens and 57 (10.4%) samples showed growth (>103 CFU/ml). A threshold of 10 bacteria/μL in flow cytometry (sensitivity = 100%) showed the best compatibility with culture. Diagnostic values in terms of sensitivity (100%), specificity (43.5%), negative predictive value (100%) and positive predictive value (17.7%) were satisfactory.
The UF-1000i flow cytometer can give results quickly and exclude UTI using the determined number of cut-off bacteria at low cost. Thus, if Sysmex UF-1000i is used, quick and accurate results can be obtained and unnecessary laboratory tests can be prevented. Also, patient convenience can be increased.
KeywordsChild Flow cytometry Urinary tract infections
SM: Conception and design, acquisition of data, analysis and interpretation of data; SC: Writing of the manuscript. SM will act as guarantor for this paper.
Compliance with Ethical Standards
Conflict of Interest
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