Evaluation of Sysmex UF1000i, a novel high-performance and high-throughput third-generation flow-cytometry screening method for the exclusion of urinary tract infection

Abstract number: P874

De Rosa R., Avolio M., Grosso S., Bruschetta G., Camporese A.

Objectives: Urinary tract infections (UTI) are the infectious diseases with the highest incidence in the hospital and community population. Although the incidence of UTI is high, a large proportion of the samples tested by a routine microbiology laboratory will show no evidence of infection with up of the 80% of the specimens with negative results for urine culture. Therefore a rapid and reliable screening method is useful to screen out negative samples, reducing unnecessary testing.

Methods: The Sysmex UF-1000i is a fully automated third-generation flow cytometry analyzer now able to better determine bacterial values with the development of a reagent system which exclusively stains bacteria. Our study investigated 1,298 urine samples collected from inpatients and outpatients and compared Sysmex UF1000i with standard urine culture tested on Cled and CNA agar plated by means of 10microliter loop.

Results: The results obtained are very interesting, especially if UF1000i is used as a screening method for negative urine samples, and comparable to data obtained from culture examination. Considering together bacteria/yeasts and/or leukocyte count (>200 bacteria, >30 yeasts and/or >100 leukocytes/microliter) in comparison with the standard culture method, diagnostic performances for Sysmex UF-1000i were: sensitivity 98.7, specificity 76.9, negative predictive value 99.5, positive predictive value 59.7.

Conclusion: The results of the present study allowed us to improve the efficiency and effectiveness of the whole diagnostic process on urine samples submitted for microbiological investigation. The high negative predictive value (99.5) and the low percentage of false negatives (less than 0.3% of the total samples analyzed), both absolutely fundamental to guarantee the diagnostic efficacy of the screening process, allow us to claim that the Sysmex UF-1000i is able to reach the diagnostic excellence that we set out to obtain. From the management point of view, one of the most interesting features that we have experienced with Sysmex UF1000i is its major contribution to improving the global turn around time, as 57.5% of samples can be reported as negatives within a few minutes of the sample admission, and can be sent to the Laboratory Information System for validation and subsequent immediate reporting in case of negative results. For physicians this should mean prompt reporting of normal samples and improvement in the quality of patient care.

Session Details

Date: 16/05/2009
Time: 00:00-00:00
Session name: 19th European Congress of Clinical Microbiology and Infectious Diseases
Location: Helsinki, Finland, 16 - 19 May 2009
Presentation type:
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