Gianluca Gessoni1, Graziella Saccani2, Sara Valverde3, Fabio Manoni4, Marco Caputo5. 1. Clinical Pathology Dept., Madonna della Navicella Hospital, Chioggia, VE, Italy. Electronic address: ggessoni@asl14chioggia.veneto.it. 2. Clinical Chemistry and Microbiology Laboratory, Orlandi Hospital, Bussolengo, VR, Italy. 3. Clinical Pathology Dept., Madonna della Navicella Hospital, Chioggia, VE, Italy. 4. Clinical Pathology Dept., Civil Hospital, Monselice, PD, Italy. 5. Clinical Chemistry and Microbiology Laboratory, Fracastoro Hospital, S. Bonifacio, VR, Italy.
Abstract
BACKGROUND: Urine culture is the most frequently requested test for a Microbiology Lab. A reliable screening tool would be of paramount importance both to clinicians and laboratorians, provided that it could get fast and accurate negative results in order to rule-out urinary tract infection (UTI). MATERIALS AND METHODS: We evaluated 1907 consecutive urine samples from outpatients. Culture was performed on chromogenic agar with 1μL loop, using 10(5)CFU/mL as a limit of positive growth. Using Sysmex Uf-1000i analyzer we evaluated bacteria forward scatter (B_FSC) and fluorescent light scatter (B_FLH) in a preliminary discrimination step for UTI caused by Gram+ or Gram- bacteria. RESULTS: We got 512 positive samples. A mono-microbial infection was observed in 490 samples; two bacterial strains were isolated in 22 samples, so 534 bacterial strains were found: 392 Gram-, 133 Gram+ and 9 yeasts. Comparing Gram+ and Gram- bacteria we observed a statistically significant difference for B_FSC but not for B_FLH. In this application experimental cut-off value for B_FSC was 25ch. Using this cut-off to perform a presumptive identification of UTI sustained by Gram-+ bacteria, we observed a SE 0.68, SP 0.84. CONCLUSION: Our data although preliminary suggest that B_FSC could be useful in presumptive exclusion of UTI caused by Gram-positive bacteria.
BACKGROUND: Urine culture is the most frequently requested test for a Microbiology Lab. A reliable screening tool would be of paramount importance both to clinicians and laboratorians, provided that it could get fast and accurate negative results in order to rule-out urinary tract infection (UTI). MATERIALS AND METHODS: We evaluated 1907 consecutive urine samples from outpatients. Culture was performed on chromogenic agar with 1μL loop, using 10(5)CFU/mL as a limit of positive growth. Using Sysmex Uf-1000i analyzer we evaluated bacteria forward scatter (B_FSC) and fluorescent light scatter (B_FLH) in a preliminary discrimination step for UTI caused by Gram+ or Gram- bacteria. RESULTS: We got 512 positive samples. A mono-microbial infection was observed in 490 samples; two bacterial strains were isolated in 22 samples, so 534 bacterial strains were found: 392 Gram-, 133 Gram+ and 9 yeasts. Comparing Gram+ and Gram- bacteria we observed a statistically significant difference for B_FSC but not for B_FLH. In this application experimental cut-off value for B_FSC was 25ch. Using this cut-off to perform a presumptive identification of UTI sustained by Gram-+ bacteria, we observed a SE 0.68, SP 0.84. CONCLUSION: Our data although preliminary suggest that B_FSC could be useful in presumptive exclusion of UTI caused by Gram-positive bacteria.
Authors: Michael Davenport; Kathleen E Mach; Linda M Dairiki Shortliffe; Niaz Banaei; Tza-Huei Wang; Joseph C Liao Journal: Nat Rev Urol Date: 2017-03-01 Impact factor: 14.432
Authors: M M Jarabo; M A Asencio; R Carranza; O Herráez; M Huertas; A Arias-Arias; O Redondo; M A Galán; M S Illescas; P Zamarrón; S Solís; S Jiménez-Alvarez Journal: Rev Esp Quimioter Date: 2018-01-29 Impact factor: 1.553