Table 1.
Results of the screening test for the identification of ESBL-producing Enterobacteriaceae. Number of isolates that were positive to the confirmatory test, DDST. Isolates that presented the ESBL-encoding genes, blaSHV and blaTEM
| ID | No. of isolates | CTXa (≤ 21 mm) | CAZa (≤ 22 mm) | CROa (≤ 23 mm) | Positive ESBL screening test | ESBL* | blaSHV gene | blaTEM gene | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| AR | RF (%) | AR | RF (%) | AR | RF (%) | AR | RF (%) | AR | RF (%) | AR | RF (%) | AR | RF (%) | ||
| Escherichia coli | 14 | 2 | 14.29% | 6 | 42.86% | 4 | 28.57 | 6 | 42.86% | 0 | 0% | 8 | 57.14% | 8 | 57.14% |
| Klebsiella spp. | 7 | 5 | 71.42% | 6 | 85.71% | 5 | 71.43 | 6 | 85.71% | 2 | 28.47 | 3 | 42.86% | 0 | 0% |
| Proteus mirabilis | 4 | 4 | 100% | 4 | 100% | 3 | 75 | 4 | 100% | 0 | 0% | 0 | 0% | 0 | 0% |
| Citrobacter spp. | 1 | 0 | 0% | 0 | 0% | 0 | 0% | 0 | 0% | 0 | 0% | 0 | 0% | 1 | 100% |
| Total: 26 | 11 | 42.31%c | 16 | 61.54%c | 12 | 42.31%c | 16 | 61.54%c | 2 | 12.5%b | 11 | 79%d | 9 | 43%d | |
| Positive ESBL screening test: 16 (38.46%) | Positive PCR: 14 (53.85%) | ||||||||||||||
CTX cefotaxima, CAZ ceftazidima, CRO ceftriaxone, ESBL extended-spectrum β-lactamase, AR absolute frequency, RF relative frequency
*Confirmatory test—DDST (double-disc synergy test)
aPhenotypic test
bPercentage associated with the number of positive isolates in the screening test
cPercentage associated with the total number of isolates
dPercentage associated with the number of isolates positive for one or both genes