Treatment of Carbapenem-Resistant Gram-Negative Bacterial Infections with Polymyxins: A Review.

Antimicrobial resistance poses a serious threat to human health. Polymyxins, as cyclic polypeptide antibiotics, include polymyxin B (PMB) and polymyxin E. Although they have different metabolic pathways, their antibacterial activities are similar. Polymyxins exert their effects through mechanisms such as disrupting bacterial cell membranes, neutralizing endotoxins, and impairing the respiratory chain. In clinical practice, polymyxins are often used in combination with other drugs to treat infections caused by carbapenem-resistant gram-negative bacteria (CRGNB). No difference in efficacy has been demonstrated between PMB and polymyxin E. An increasing amount of evidence suggests that combination therapy is not superior to monotherapy. The combination of intravenous administration and nebulization can help improve microbial clearance. Compared with other antibiotics, polymyxins have not shown obvious survival benefit. Polymyxins are associated with nephrotoxicity and neurotoxicity, and it is essential to closely monitor for related adverse events during the course of treatment.