Why Do Carbapenem Antibiotics Cause Higher Rates of Clostridium difficile & Superinfections?

Khalid Eljaaly, PharmD, MS, CAPPS, BCPS, Contagion Editorial Advisory Board member, postdoctoral research fellow on infectious diseases and antimicrobial stewardship, the University of Arizona, College of Pharmacy, explains why carbapenem antibiotics cause higher rates of C. diff and superinfections.

Interview Transcript (slightly modified for readability)

“We believe [that] it is because carbapenem has [more] broad-spectrum of activity than other antibiotics. This leads to inhibition of microflora and [the] overgrowth of opportunistic organisms.

We found that when we compared imipenem or meropenem versus other antibiotics, that it was associated with more superinfections and Clostridium difficile. We had around 8 randomized clinical trials that looked at superinfections, [and so] we were able to do a subgroup analysis comparing a carbapenem versus the typical comparator, which is an antipseudomonal beta-lactam, such as piperacillin/tazobactam or cefepime, and we found a higher [incidence] of superinfection with carbapenem, compared with an antipseudomonal beta-lactam.”