Who doesn’t love to pick up random bits of information while they’re in line for their coffee or their morning signout? Here are 5 helpful pieces of information on antimicrobials to start off your day!
1.Cefepime vs. Piperacillin-tazobactam
Cefepime – cephalosporin
– DOES NOT cover gut anaerobes
– DOES NOT cover Enterococcus spp.
Piperacillin-tazobactam – penicillin derivative
– DOES cover gut anaerobes
– DOES cover penicillin-sensitive Enterococcus spp.
| Antibiotic | Cefepime | Piperacillin/tazobactam |
| Class | Cephalosporin | Penicillin derivative |
| Gut anaerobic coverage? | No | Yes |
| Enterococcus coverage? | No | Yes (if susceptible) |
2. Cephalosporins in general DO NOT cover Enterococcus spp.
3. Ertapenem vs. meropenem vs. imipenem vs. doripenem
Ertapenem – DOES NOT cover Pseudomonas spp.
Meropenem/Imipenem/Doripenem – DO cover Pseudomonas spp.
*None of the carbapenems cover MRSA
4. Ineffective antimicrobials
Daptomycin – inactivated by the surfactant in the lungs
– DO NOT use daptomycin to treat lung infections
*Remember: Linezolid, Lung (you can use Linezolid for lung infections)
Echinocandins (ex. micafungin, caspofungin, anidulafungin) – do not reach therapeutic levels in the urinary tract
– DO NOT use echinocandins to treat pyelonephritis or urinary tract infections
Tigecycline – accumulates in the tissues and has low concentration levels in the bloodstream
– DO NOT use tigecycline to treat bloodstream infections
5. Bone marrow toxicity due to linezolid increases after 2 weeks of exposure
– Avoid using linezolid for more than two weeks at a time when possible
Do you have any random facts of ID knowledge? Let me know in the comments section below!
References:
1. Mandell, Douglas, and Bennett. Principles and practice of infectious diseases. Philadelphia, PA: Churchill Livingstone/Elsevier, c2010. 7th edition.
2. Zhanel, G.G. et al. 2007. Comparative review of the carbapenems. Drugs. 67(7):1027-1052.
3. Gerson, S.L. et al. 2002. Hematologic effects of linezolid: summary of clinical experience. Antimicrobial Agents and Chemotherapy. 46(8): 2723-2726.
4. Malani, A.N. et al. 2014. Candida urinary tract infections: treatment options. 5(2): 277-284.
5. Jeu, L. et al. 2004. Daptomycin: a cyclic lipopeptide antimicrobial agent. Clinical Therapeutics. 26(11): 1728-1757.
Peer-reviewed by Jeff Pearson, PGY-2 pharmacy resident
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