Colistinassociated

Colistin-associated refers to adverse effects and complications linked to the antibiotic colistin, also known as polymyxin E. Colistin is a polymyxin antibiotic used as a last-resort option against certain multidrug-resistant Gram-negative bacteria, including Pseudomonas aeruginosa, Acinetobacter baumannii, and some Enterobacterales. Its use has expanded with rising antimicrobial resistance, but toxicity remains a major concern.

The most well-described adverse effects are nephrotoxicity and neurotoxicity. Nephrotoxicity can manifest as acute kidney injury with elevated creatinine and reduced urine output, while neurotoxicity may present as paresthesias, dizziness, lethargy, ataxia, or, in severe cases, encephalopathy. Both toxicities are thought to be dose- and duration-dependent and may be influenced by critical illness and concomitant nephrotoxic or neurotoxic drugs.

Incidence of toxicity varies across studies, with nephrotoxicity reported in a significant portion of patients receiving colistin and neurotoxicity occurring less frequently but being clinically important. Risk factors include higher or prolonged dosing, older age, preexisting kidney disease, sepsis or shock, multi-organ failure, and concomitant nephrotoxic or neurotoxic medications such as aminoglycosides or vancomycin.

Management emphasizes avoidance or minimization of toxicity through careful dosing considerations, monitoring of renal function and electrolytes, and prompt modification or discontinuation of therapy if toxicity develops. Colistin is administered as colistin methanesulfonate, a prodrug, which complicates dosing and exposure. In settings where alternatives are limited, therapeutic drug monitoring and renal function surveillance help balance efficacy with safety.

In summary, colistin-associated toxicities require vigilant risk assessment and close clinical monitoring, reflecting the antibiotic’s role as a critical but high-risk option for treating resistant infections.