Let’s say you get a septic patient who has a history of “ESBL.” What does this mean, and what can you empirically treat with?
ESBL, or extended spectrum beta lactamases, refers to a group of bacteria that have developed resistance against beta-lactam antibiotics: penicillins, cephalosporins, and aztreonam. Common suspects include fecal and urinary organisms like E. coli and Klebsiella
If you can’t use penicillins (piperacillin-tazobactam or Zosyn) or cephalosporins (which include heavy hitters like cefepime and ceftazidime), what are you left with? Carbapenems: meropenem is used more frequently, although imipenem and ertapenem are also options. It is sometimes possible to “power through” with high-dose cefepime (2 g q8h) but it’s best to have bacterial sensitivities before plowing down this path.
You also have the option of adding on fosfomycin and/or tigecycline sensitivities if you are stuck treating a difficult UTI.