title: Rapid differentiation of cocci/mixed bacteria from rods in voided urine culture of women with uncomplicated urinary tract infections.
abstract: OBJECTIVE
  To evaluate the ability of laser flow cytometry to predict cocci/mixed growth in the pre-analytical phase of urine specimens.
  
  
  METHODS
  We retrospectively reviewed urine samples from women with uncomplicated urinary tract infections from urologic clinics for study. Urine analyses were performed with laser flow cytometry (UF1000i, Sysmex, Kobe, Japan) and then diagrams were generated (forward scatter vs. fluorescent light scatter). Each specimen (bacteria count >357 BACT/μL) was classified as either cocci bacteria or rods/mixed growth according to the diagrams. Standard urine cultures were performed, and the agreement between cultures and the UF1000i interpretations was analyzed with kappa statistics.
  
  
  RESULTS
  Finally, 491 specimens met the criteria for analysis. Among the 376 specimens with single bacteria growth, there were 26 gram-positive cocci (13 Streptococci spp., 7 Staphylococci spp., 6 Enterococci spp.), 1 gram-positive rods (Corynebacterium spp.), and 349 gram-negative rods (273 Escherichia coli, 33 Klebsiella spp., 29 Proteus spp., 6 Citrobacter spp., 4 Enterobacter spp., 3 Pseudomonas spp., and 1 Providencia spp.). There were 115 specimens with two bacteria species or more that were regarded as mixed growth. Agreement of rods or cocci/mixed growth between the laser flow cytometry and urine cultures yielded a kappa value of 0.58. The positive and negative predictive rate of the UF1000i for cocci/mixed growth in voided urine culture was 81.8% and 84.7%, respectively.
  
  
  CONCLUSIONS
  Through laser flow cytometry, we can predict growth of cocci/mixed growth in the pre-analytical phase of urine culture, thus avoiding unnecessary urine culture and waiting time.
authors.affiliation: Division of General Laboratory, Taipei Tzu Chi General Hospital, Buddhist Tzu Chi Medical Foundation, Taipei, Taiwan.
authors.forename: Chun-Chun
authors.initials: CC
authors.lastname: Yang
authors.affiliation: Division of Urology, Taipei Tzu Chi General Hospital, Buddhist Tzu Chi Medical Foundation, Taipei, Taiwan.|Medical College of Buddhist, Tzu Chi University, Hualien, Taiwan.
authors.forename: Stephen Shei-Dei
authors.initials: SS
authors.lastname: Yang
authors.affiliation: Division of General Laboratory, Taipei Tzu Chi General Hospital, Buddhist Tzu Chi Medical Foundation, Taipei, Taiwan.
authors.forename: Hui-Ching
authors.initials: HC
authors.lastname: Hung
authors.affiliation: Department of Urology, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: I-Ni
authors.initials: IN
authors.lastname: Chiang
authors.affiliation: Division of Urology, Taipei Tzu Chi General Hospital, Buddhist Tzu Chi Medical Foundation, Taipei, Taiwan.|Medical College of Buddhist, Tzu Chi University, Hualien, Taiwan.
authors.forename: Chiung-Hui
authors.initials: CH
authors.lastname: Peng
authors.affiliation: Division of Urology, Taipei Tzu Chi General Hospital, Buddhist Tzu Chi Medical Foundation, Taipei, Taiwan.|Medical College of Buddhist, Tzu Chi University, Hualien, Taiwan.
authors.forename: Shang-Jen
authors.initials: SJ
authors.lastname: Chang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015373:Bacterial Typing Techniques / Q000379:methods*; D060085:Coinfection / Q000175:diagnosis / Q000382:microbiology*; D005260:Female; D005434:Flow Cytometry / Q000379:methods*; D006095:Gram-Positive Cocci / Q000166:cytology* / Q000302:isolation & purification; D016987:Gram-Positive Rods / Q000166:cytology* / Q000302:isolation & purification; D006801:Humans; D008875:Middle Aged; D012189:Retrospective Studies; D014552:Urinary Tract Infections / Q000175:diagnosis / Q000382:microbiology*
keywords: bacterial morphology; diagnosis; laser flow cytometry; urinary tract infections; urine culture