Extended Spectrum Beta-Lactamase (ESBL) Producing Organisms

Considered resistant to all beta-lactams and beta-lactam combinations, except for carbapenems, which are the preferred therapy.

These organisms may be reported as susceptible to Pip-Tazo or other beta-lactamase inhibitor combinations, however treatment failures have been described.

Often resistant to fluoroquinolones, TMP-SMX, and aminoglycosides via other mechanisms.

For UTI only - may be susceptible to nitrofurantoin and fosftomycin.

Susceptibility Testing
Possible ESBL on automated systems require referral to the Public Health Microbiology Laboratory (St. John's) for ESBL confirmation by Kirby Bauer testing.

Confirmed ESBL are referred to the National Microbiology Laboratory for typing.