carbapenems

Carbapenems are a class of beta-lactam antibiotics known for their broad spectrum and stability to many beta-lactamases. They act by inhibiting bacterial cell wall synthesis through binding to penicillin-binding proteins, producing time-dependent bactericidal activity.

Common members of the class include imipenem, meropenem, ertapenem, and doripenem. Imipenem is co-formulated with cilastatin to prevent renal degradation, while the other agents do not require this combination. Carbapenems generally have activity against a wide range of Gram-positive cocci, Gram-negative rods, and anaerobes, but activity can vary by agent. Ertapenem lacks reliable activity against Pseudomonas aeruginosa and Acinetobacter species. MRSA and Enterococcus faecium are typically resistant, and Pseudomonas coverage is strongest with meropenem and doripenem in many settings.

Clinical use and administration: Carbapenems are reserved for severe, complicated, or high-risk infections where resistant organisms are suspected or confirmed. They are administered by the parenteral route and are primarily renally cleared. Indications include complicated intra-abdominal infections, hospital-acquired pneumonia, community-acquired pneumonia in some contexts, complicated urinary tract infections, gynecologic infections, bacteremia, and febrile neutropenia. Adverse effects are generally infrequent but can include nausea, diarrhea, rash, and hypersensitivity reactions; high doses or renal impairment may increase the risk of seizures, particularly with imipenem.

Resistance and stewardship: The spread of carbapenemase-producing organisms (such as KPC, NDM, VIM, IMP, and OXA-48 types) and other mechanisms can confer resistance, leading to carbapenem-resistant Enterobacteriaceae. Use is balanced with antimicrobial stewardship, reserving carbapenems for appropriate indications to preserve their effectiveness.