Intrinsic resistance to Ampicillin and lower generation cephalosporins. With exposure to beta-lactams, induction or de-repression can occur and confer resistance to third generation cephalosporins.
Susceptible to carbapenems
Usually susceptible to fluoroquinolones, TMP-SMX, and aminoglycosides which are appropriate targeted therapy options.
Using non-carbapenem beta-lactams (i.e. Pip-Tazo, Ceftriaxone) when reported as susceptible likely reasonable for SIMPLE infections requiring SHORT duration.
Usually sensitive to aztreonam.