Table 1.
Characteristics of the 19 AmpC-positive isolates in this study.a
| No. of isolates | AmpC group | Cephalosporin phenotype |
AmpC disk test | Cephamycin Hodge test | AmpC Etest | Cefoxitin/cefoxitin+ boronic acid | ||||
|---|---|---|---|---|---|---|---|---|---|---|
| CAZ | CTX | FOX | CT | FEP | ||||||
| 5 | CIT | S | S | S | S | S | − | − | − | + |
| 7 | CIT | S | S | S | S | S | − | − | − | + |
| 9 | MOX | R | R | R | R | R | − | − | IR | + |
| 11 | MOX | R | R | R | R | R | + | − | IR | + |
| 12 | MOX | R | R | R | R | R | − | − | IR | + |
| 17 | MOX | R | R | R | R | R | − | − | + | + |
| 1 | MOX | R | R | S | S | R | − | − | − | + |
| 21 | MOX | S | S | S | S | S | − | − | − | + |
| 22 | MOX | R | R | R | S | S | + | + | − | + |
| 3 | DHA | R | R | R | R | S | + | − | IR | + |
| 6 | EBC | S | S | S | S | S | − | − | − | + |
| 51 | EBC | R | R | S | S | R | − | − | − | + |
| 49 | CIT | R | R | S | S | R | − | − | − | + |
| 55 | CIT | R | R | R | R | R | + | + | IR | + |
| 60 | CIT | R | R | R | S | R | + | + | − | + |
| 68 | CIT | R | R | R | R | R | − | − | IR | + |
| 75 | CIT | R | R | R | R | S | + | + | IR | + |
| 89 | CIT | R | R | R | R | R | − | − | IR | + |
| 27 | EBC | R | R | R | R | S | + | + | + | + |
CAZ = ceftazidime; CT = cefotetan; CTX = cefotaxime; FEP = cefepime; FOX = cefoxitin; IMI = imipenem; IR = inconclusive result.
a
Results were rated inconclusive if the minimum inhibitory concentrations exceeded the scale of the Etest for cefotetan alone and/or cefotetan in combination with cloxacillin (Etest AmpC).