Review Article

Automated Flow Cytometry: An Alternative to Urine Culture in a Routine Clinical Microbiology Laboratory?

Table 1

Summary of eligible studies.

Reference
(country)
Patients and samplesReference
Counts
Cutoff
Values
SE/SP/NPV/ER%

Monsen and Rydén 2015 
(Turkey) [21]
4458 urine samples from adults>104 CFU/mL50 BAC/µL
30 WBC/µL
1/49.7/1/44.8

García-Coca et al., 2017
(Spain) [22]
17483 urine samples from 85% women and 14.7% (median age 47 years). 97.4% outpatients and 2.6 hospitalized subjects>105 CFU/mL>200 BAC/µL
>40 WBC/µL
AUC (BAC) count:
0.79
AUC (WBC) count:
0.60
ER: 48

Kulkarni and Nigrin 2013 
(Netherlands) [23]
7322 urinary samples from
60% inpatients and 40% outpatients (average age 66 years)
>105 CFU/mL>200 BAC/µL0.93/0.63/0.96/49

Íñigo et al.
(2016) [24]
(Spain)
1934 urine samples: MSU (89.14%), catheterized urine (9.98%), pediatric urine bags (0.72%), suprapubic aspiration (0.16%), belonging to 56%  ♀ and 44%  ♂ (51.19% hospitalized patients and 48.81% outpatients)>102 CFU/mL460 BAC/µL
40 WBC/µL
0.98/0.76/0.99/57

Gessoni et al., 2015
(Italy) [25]
2335 MSU from adult patients (41% inpatients and 59% outpatients), between 15 to 91 years old (♀: 34%, ♂: 66%)≥105 CFU/mL175 BAC/µL0.95/0.80/—/50

Martín-Gutiérrez et al., 2015 
(Spain) [26]
346 MSU collected from elderly outpatients with a median age of 76 years (♀: 43%, ♂: 56%)≥105 CFU/mL for women
≥104 CFU/mL for men
200 BAC/µL0.99/0.91/0.99/60

Manoni et al., 2009 
(Italy) [27]
372 MSU specimens from 167 ♂ and 205 ♀ (57.37% outpatients and 42.63% inpatients)>105 CFU/mL14.2 BAC/µL
6.7 WBC/µL
14.2 BAC/µL
0.8/0.58/0.86/—/—
0.95/0.44/0.95/30.6

Marschal et al., 2012
(Germany) [28]
572 urine samples (31.8% catheterized, 65.5% MSU and 2.7% not specified), from 513 patients (27.9% outpatients, 72.1% inpatients) ♀: 48.9% and ♂: 51.1% (mean age of 54.2 years)>102 CFU/mL>30 BAC/µL
>20 WBC/µL
0.80/0.78/—/—

Gutiérrez-Fernández et al., 2012  
(Spain) [29]
1225 urine samples (urine catheter, MSU or pediatric bags) from 158 inpatients (27 catheterized adults, 33 children, 98 inmunocompromised adults) and 1067 outpatients (464 adults and 603 pregnant women).>105 CFU/mL690 BAC/µL
38 WBC/µL
0.92/0.65/0.97/—

Broeren et al.
(2011) (Netherlands)
[14]
1577 urine samples collected from 681 outpatients (196  ♂) and 896 (403  ♂) from hospitalized patients<105 CFU/mL
<104 CFU/mL
230 BAC/µL
39 BAC/µL
0.96/0.78/0.99/52
0.82/0.83/0.95/28

Kadkhoda et al. 2011
(Canada) [30]
2496 (75%) MSU and 25% catheterized urine (patients origin not informed)≥104 CFU/mL
of up two uropathogens
≥105 CFU/mL
Non uropathogens
20 BAC/µL0.93/0.69/—/35

Pieretti et al. 2010
(Italy) [31]
703 MSU from 18.2% hospitalized patients and 81.8% outpatients (70.6% females and 29.4% males)>104 CFU/mL65 BAC/µL
100 WCB/µL
0.98/0.62/0.98/43

van der Zwet et al. 2010
(Dutch) [32]
358 urine samples (patients origin not informed)>104 CFU/mL50 BAC/µL
20 WBC/µL
1/0.8/0.59/42

De Rosa et al. 2010
(Italy) [33]
1349 urine samples (patients origin not informed)>104 CFU/mL for adult
>106 CFU/mL for children.
170 BAC/µL
150 WBC/µL
0.98/0.76/0.99/57

Shang et al. 2013 
(China) [34]
313 urine samples, belonging inpatients and outpatients>105 CFU/mL for gram (−)
>104 CFU/mL for gram (+)
100 BAC/µL
56 WBC/µL
0.86/0.95/0.94/50

Hu et al. 2010 [35]
(China)
308 urine samples from outpatients>105 CFU/mL for gram (−)
>104 CFU/mL for gram (+)
160 BAC/µL0.81/0.83/0.89/55

Kouri 2000 
(Italy) [36]
1463 MSU samples from adults>105 CFU/mL>125 BAC/µL
>40 WBC/µL
0.99/0.77/0.98/—

MSU: midstream urine sample; WBC: white blood cells; BAC: bacteria, NPV: negative predictive value; CFU: colony forming units; ER: elimination rate; AUC: area under the ROC curve.