Published on 9 de enero de 2026 | http://doi.org/10.5867/medwave.2026.01.3049
Identification and susceptibility profile of microorganisms isolated directly from urine in a cross-sectional study using matrix-assisted laser desorption/ionization time-of-flight and Phoenix M50
Results of direct identification of Gram-positive microorganisms compared with culture identification results.
Direct ID Using MALDI-TOF (Number of samples)
Media score ID
Score (Minimum - Maximum)
Culture results
Concordance (%)
E. faecalis (13)
1.93
1.35 - 2.20
E. faecalis (13)
100
St. agalactiae (4)
1.86
1.77 - 1.95
St. agalactiae (4)
100
E. faecium (2)
2.21
2.21
E. faecium [1], negative culture (1)
50
S. saprophyticus (1)
1.83
1.83
S. saprophyticus (1)
100
E. coli (2)
2.02
1.93 - 2.20
E. faecalis (1), negative culture (1)
0
K. pneumoniae (2)
1.9
1.79 - 1.97
Negative culture (2)
0
Not identified (39)
-
-
Negative culture (23), E. faecalis (3), E. faecium (2), S. saprophyticus (2),
Not applicable
ID, identification.
Only E. coli and K. pneumoniae were selected for antimicrobial suceptibility testing analysis because of their high prevalence. The results of the evaluation for E. coli (see Table 5) indicate that most antibiotics meet the required standards. However, five antibiotics do not meet all criteria. Ampicillin and ceftriaxone fail to meet the ME criteria with a rate of 3.4%. Ertapenem does not meet the CA (87.7%), EA (87.7%), and ME (9.6%) criteria, all below the required 90%, indicating issues with categorical and essential agreement. Meropenem meets CA (94.9%) and EA (91.5%) but exceeds the ME limit with 5.2%, which is above the acceptable 3%, and finally, piperacillin/tazobactam exceeds the minor error limit (13%).
