Extended-spectrum β-lactamases: Difference between revisions

From IDWiki
No edit summary
()
 
Line 66: Line 66:
== Management ==
== Management ==


* Carbapenem, with [[meropenem]] or [[imipenem]] preferentially, though [[ertapenem]] can be considered if no septic shock[[Pichia kudriavzevii]]
* In some patients, can consider [[piperacillin-tazobactam]], [[amoxicillin-clavulanic acid]], or [[fluoroquinolones]]
* For non-severe [[UTI]] without septic shock, can consider [[co-trimoxazole]], [[aminoglycosides]], or [[fosfomycin]] (IV)
* See also [[Carbapenem-resistant organisms]]
* See also [[Carbapenem-resistant organisms]]

Latest revision as of 02:22, 14 November 2024

Background

Identification

Screening for ESBL production
Bacterium Antibiotic Disc Diffusion Broth Microdilution
Klebsiella pneumoniae, Klebsiella oxytoca, and Escherichia coli cefpodoxime ≤17 mm ≥8 μg/mL
ceftazidime ≤22 mm ≥2 μg/mL
aztreonam ≤27 mm ≥2 μg/mL
cefotaxime ≤27 mm ≥2 μg/mL
ceftriaxone ≤25 mm ≥2 μg/mL
Proteus mirabilis cefpodoxime ≤22 mm ≥2 μg/mL
ceftazidime ≤22 mm ≥2 μg/mL
cefotaxime ≤27 mm ≥2 μg/mL
  • Organisms that screen positive have further testing to determine the presence of an ESBL
  • Class A, for all organisms that screen positive,
  • Class B, for organisms that are also resistant to carbapenems
  • Class C, for organisms that are non-susceptible to cefoxitin
    • A double-disc diffusion method is used to test if the results for cefoxitin are attenuated by cloxacillin (that is, if the isolate becomes even more susceptible)
    • An increase in the zone of ≥4 mm is positive for AmpC (Class C ESBL) phenotype
  • Class D, difficult to identify with phenotypic testing

Management