Volume 29, Number 7—July 2023
Research Letter
Extensively Drug-Resistant Shigella flexneri 2a, California, USA, 2022
Table
Drug | MIC, mcg/mL | Interpretation | Detected AMR gene |
---|---|---|---|
Amoxicillin + clavulanate | 32 | Resistant† | blaOXA-1, blaCTX-M-15 |
Ampicillin | >32 | Resistant† | blaOXA-1, blaCTX-M-15 |
Azithromycin | 32 | Resistant | mph(A) |
Cefazolin | >32 | Resistant† | blaOXA-1, blaCTX-M-15 |
Cefepime | 4 | Susceptible, dose dependent† | blaCTX-M-15 |
Ceftazidime | 4 | Susceptible† | blaCTX-M-15 |
Ceftazidime/avibactam | <2 | Susceptible† | None |
Ceftriaxone | 64 | Resistant† | blaCTX-M-15 |
Ciprofloxacin | >4 | Resistant | qnrS1, gyrA D87N+S83L |
Doxycycline | >16 | Resistant† | tet(B) |
Ertapenem | <0.25 | Susceptible† | None |
Imipenem | <1 | Susceptible† | None |
Levofloxacin | >8 | Resistant† | qnrS1, gyrA D87N+S83L |
Meropenem | <0.25 | Susceptible† | None |
Minocycline | 4 | Susceptible† | tet(B) |
Piperacillin + tazobactam | <8 | Susceptible† | blaOXA-1, blaCTX-M-15 |
Trimethoprim/sulfamethoxazole | >4/80 | Resistant | dfrA17, sul1 |
Fosfomycin | Not performed‡ | Not performed‡ | Not applicable |
*AMR, antimicrobial resistance; AST, antimicrobial susceptibility testing. †AST not initially included in primary report and performed and reported at physician request. ‡AST not performed because of lack of interpretive guidelines by the Clinical and Laboratory Standards Institute.
Page created: May 19, 2023
Page updated: June 21, 2023
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