A-287 Evaluation of Urinalysis Reflex to Culture in Long-Term Care Facilities: Is It Worth it?

Abstract

Abstract Background Urinary Tract Infection (UTI) is one of the second common infections among the geriatric population. It is more common in women than men and the incidence increases with age. UTI can cause serious complications and it is a significant cause of morbidity and death. The high mortality rate is largely due to delayed presentation and the development of bacteremia/sepsis. Physicians rely heavily on urinalysis to diagnose UTI, and it is one of the most frequently requested tests; however, the need to reflect to urine culture became more in demand to cut the cost of test not needed without the sacrificing of patient care. Methodology 4307 urine samples were collected for urinalysis and culture from residents in Long-Term Care Facilities (LTCF) over a period of 5 weeks. Urinalysis and microscopy were done using IQ WORKCELL automated system. All the specimens were cultured; the culture was done using MicroScan Walkaway96 conventional panels. We used urine culture as the reference standard, no growth or <10 000 colony-forming unit/mL were considered negative, cultures with >50 000 colonies colony-forming unit/mL were considered positive. UA is considered positive if it was positive leukocyte esterase, WBC > 5, nitrate, or had >moderate bacteria. We compared positive UA to the culture outcome. Statistical analyses were done using Analyse-it. Results Women represented 64.7% of the samples tested; the positivity rate was 49.2% (52.3% for women and 43.4% for men) and 7.0% of the all the cultures had mixed flora. Urinalysis identified 3038 as positive UA, only 1941 (63.9%) had positive culture and 846 (43.6%) had negative culture. Urinalysis identified 1269 samples as negative, 176 samples (13.9%) of them had positive culture. Conclusion The use of negative urinalyses to reflex to culture would help eliminating the majority of the cultures that are not necessary. However, avoiding the culture will risk missing infection in 13.9% of the negative urinalysis samples. In addition, more than one third of the positive urinalysis will require unnecessary cultures. Although the use of reflex will help eliminating the unnecessary culture, we have to remember that urinalysis and microscopy still lack the sensitivity and specificity to be used alone to diagnose urinary tract infection; urinalysis should not be the only marker for UTI, it should be used in conjunction with patients clinical diagnosis. The high positivity rate for UTI in LTCF adds to the complication of the reflex testing. More work needed to establish better parameters and algorithm to be used when screening patients for UTI using urinalysis.