Molecular mechanisms and genetic epidemiology of colistin resistance in Pseudomonas aeruginosa: a systematic review and meta-analysis

Abstract

Colistin is a last-resort antibiotic for multidrug-resistant (MDR) and extensively drug-resistant (XDR) P. aeruginosa infections; however, colistin-resistance is rising globally. This study synthesizes global data on colistin-resistance mechanisms, high-risk clones (HRCs), and One Health dynamics. This study screened 1318 records and analyzed 40 studies using PRISMA guidelines. The literature search was conducted from March 01 and April 30, 2025. Data extraction covered colistin-resistance genes, sequence types (STs), and co-resistance patterns. The results reveal that colistin resistance is primarily driven by chromosomal mutations (in pmrAB and phoPQ) and plasmid-borne mcr genes with high detection of mcr-1. HRCs were dominant globally, and most colistin-resistant isolates exhibited co-resistance to β-lactams/carbapenems, amplifying MDR/XDR threats. Resistance rates showed regional heterogeneity in Asia, Europe, and America compared to Africa and the Middle East. The study suggests that regulated colistin use, enhanced genomic surveillance, regular antibiotic stewardship programs, development of rapid diagnostics and novel therapies are necessary to combat the spread of MDR/XDR P. aeruginosa strains.