Abstract:

Objective To investigate the role of urinary sediment analysis by UF-1000i urinalysis analyzer combined with serum procalcitonin（PCT） determination in the diagnosis of urinary tract infection. Methods A total of 1 372 urine specimens were collected in sterile process and determined for urinary bacterial culturing and the cut-off values of bacterium and white blood cell counts by UF-1000i. The result of urinary bacterial culturing was used as golden standard. The sensitivities and specificities were evaluated. The consistency of bacterium scatter diagram information of UF-1000i and urinary bacterial culturing was analyzed. Serum PCT levels of urinary bacterial culturing positive group,urinary bacterial culturing negative group,UF-1000i positive group and UF-1000i negative group were compared. Results The cut-off value of white blood cell count was 27.5/μL,and the cut-off value of bacterium count was 143.5 /μL. Using positive bacterium and white blood cell counts as screening parameters,the specificity was 92.7%,and the false negative rate was 30.8%. Using positive bacterium or white blood cell count as screening parameter,the specificity was 55.3%,and the false positive rate was 44.7%. The consistency of bacterium scatter diagram information of UF-1000i and urinary bacterial culturing was 57%. The level of serum PCT in UF-1000i positive group was higher than those in UF-1000i negative group and normal control group（P<0.05）,but there was no statistical significance for UF-1000i positive group compared with urinary bacterial culturing positive group（P>0.05）. UF-1000i positive group combined with serum PCT determination can improve specificity for urinary tract infection. Conclusions UF-1000i white blood cell and bacterium counts and serum PCT level could be used for screening urinary tract infection.

Key words: Urinary bacterial culturing, Urinary sediment, Procalcitonin, Urinary tract infection