Comparison of microbial growth on chromogenic media vs_ reference method_
| Bacterial strains | Number of isolates (n) | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| The reference method | Chromogenic media | ||||||||
| Family or genus (n) | Species (by VITEK 2 Compact) and isolates number | Columbia Agar + 5% sheep blood (COL) | MacConkey Agar (MAC) | ChromID® CPS® Elite (CPSE, bioMérieux) | BD CHROMagar Orientation Medium (ORI, Becton Dickinson) | Brillance UTI Clarity Agar (UTI C, Oxoid) | CHROMagar™ Orientation (BioMaxima) | CHROMagar™ Orientation (ORIE, Graso) | |
| Gram-negative rods (n = 62) | |||||||||
| Enterobacteriaceae (n = 61) | Citrobacter freundii | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| Enterobacter cloacae | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | |
| Escherichia coli | 33 | 32 | 31 | 32 | 30 | 33 | 31 | 33 | |
| Klebsiella pneumoniae | 16 | 16 | 15 | 16 | 16 | 16 | 16 | 16 | |
| Klebsiella oxytoca | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | |
| Morganella morganii | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | |
| Proteus mirabilis | 6 | 6 | 6 | 6 | 6 | 6 | 6 | 6 | |
| Proteus vulgaris | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | |
| Non-fermenting rods (n = 1) | Acinetobacter lwofii | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 1 |
| Gram-positive cocci (n = 47) | |||||||||
| Enterococci (n = 22) | Enterococcus avium | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 |
| Enterococcus faecalis | 20 | 20 | 0 | 18 | 20 | 18 | 19 | 20 | |
| Enterococcus hirae | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | |
| Staphylococci (n = 21) | Staphylococcus epidermidis | 9 | 9 | 0 | 8 | 6 | 8 | 8 | 9 |
| Staphylococcus haemolyticus | 4 | 4 | 0 | 4 | 3 | 3 | 3 | 3 | |
| Staphylococcus hominis | 7 | 7 | 0 | 6 | 6 | 6 | 6 | 6 | |
| Staphylococcus warnerii | 1 | 1 | 0 | 1 | 0 | 1 | 1 | 0 | |
| Streptococci (n = 4) | Streptococcus agalactiae | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 |
| Streptococcus viridans group | 3 | 3 | 0 | 3 | 3 | 3 | 3 | 3 | |
Sensitivity, specificity, positive (PPV) and negative predictive values (NPV) of chromogenic media for UTI diagnosis_
| Parameters | Chromogenic media | |||||
|---|---|---|---|---|---|---|
| ChromID® CPS® Elite (CPSE, bioMérieux) | BD CHROMagar Orientation Medium (ORI, Becton Dickinson) | Brillance UTI Clarity Agar (UTI C, Oxoid) | CHROMagarTM Orientation (BioMaxima) | CHROMagarTM Orientation (ORIE, Graso) | Mean value | |
| Qualitative cultures for all detected pathogens (p > 0.99) | ||||||
| Sensitivity (%) | 94.7 | 91.7 | 89.6 | 94.4 | 97.2 | 93.5 |
| Specificity (%) | 97.7 | 95.5 | 97.7 | 97.7 | 97.7 | 97.3 |
| Positive predictive value (PPV) (%) | 98.9 | 98.0 | 98.4 | 99.0 | 99.1 | 98.7 |
| Negative predictive value (NPV) (%) | 89.4 | 82.4 | 85.7 | 87.8 | 93.3 | 87.7 |
| Qualitative cultures of E. coli | ||||||
| Sensitivity (%) | 96.8 | 90.1 | 100 | 93.3 | 100 | 96.0 |
| Semi-quantitative cultures for all detected pathogens (p = 0.9) | ||||||
| Sensitivity (%) | 85.2 | 80.2 | 75.0 | 81.0 | 85.1 | 81.3 |
| Specificity (%) | 85.7 | 82.4 | 91.3 | 82.7 | 82.4 | 84.9 |
| Positive predictive value (PPV) (%) | 91.5 | 90.0 | 92.3 | 90.0 | 90.5 | 90.9 |
| Negative predictive value (NPV) (%) | 76.4 | 67.7 | 72.4 | 69.4 | 73.7 | 71.9 |
| Semi-quantitative cultures of E. coli | ||||||
| Sensitivity (%) | 93.1 | 84.0 | 95.2 | 87.1 | 93.6 | 90.6 |
Detection of bacteria in mono- and mixed urine culture on chromogenic media for UTI diagnosis_
| Number of isolates in a clinical specimen | Number of clinical specimens (urine) | Number of all isolates in all clinical specimens | Total number of isolates (% of the number cultured on reference media) | ||||
|---|---|---|---|---|---|---|---|
| Chromogenic media | |||||||
| ChromID CPS Elite (CPSE, bioMérieux) | BD CHROMagar Orientation Medium (ORI, Becton Dickinson) | Brillance UTI Clarity Agar (UTI C, Oxoid) | CHROMagarTM Orientation (BioMaxima) | CHROMagarTM Orientation (ORIE, Graso) | |||
| 1 | 31 | 31 | 30 (96.8%)† | 29 (93.6%)† | 31 (100%) | 30 (96.6%)† | 31 (100%) |
| 2 | 12 | 24 | 23 (95.8%)† | 22 (91.7%)†, ¶ | 22 (91.7%)§ | 23 (95.8%)¶ | 24 (100%) |
| 3 | 7 | 21 | 21 (100%) | 18 (85.7%)†, ‡, †† | 17 (81.0%)†, ‡, § | 19 (90.5%)† | 20 (95.3%)† |
| 4 | 7 | 28 | 25 (89.3%)†, ¶ | 25 (89.3%)†, ‡, ¶ | 27 (96.4%)† | 25 (89.3%)†, §, ¶ | 26 (92.6%)†, ‡ |
| 5 | 1 | 5 | 5 (100%) | 5 (100%) | 5 (100%) | 5 (100%) | 5 (100%) |