Biofilm formation and antibiofilm strategies in the Achromobacter genus: a scoping review

Biofilm formation plays a major role in bacterial persistence across clinical and environmental settings, with particular significance in chronic infections. Achromobacter spp. are environment-borne emerging opportunistic pathogens increasingly recognized in biofilm-associated diseases. This scoping review summarizes evidence on the prevalence and determinants of biofilm formation in Achromobacter and examines the antibiofilm effects of various strategies. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews guidelines, a comprehensive search of the PubMed-MEDLINE database was conducted from inception to June 2026 using the terms “ Achromobacter ” AND “biofilm”. Of 124 records identified, 79 studies were included. Data interpretation was challenged by methodological heterogeneity and variable confidence in species identification. In vitro , ex vivo , and in vivo models have been used, yielding complementary but sometimes conflicting results, underscoring the need for standardized protocols. However, biofilm formation appears to be widespread in Achromobacter . Statistical analyses of results from comparable studies showed that biofilm-forming capacity is independent of the clinical (cystic fibrosis or not) origin of the isolates while Achromobacter xylosoxidans , the most commonly isolated species in human infections, displays a higher prevalence of biofilm-producing isolates than other species. Biofilm formation may vary over time during chronic colonization or environmental persistence, probably reflecting distinct selective pressures. Among them, polymicrobial environments are hotspots of biotic interactions, where Achromobacter sp. can affect the biofilm formation of other pathogens like Pseudomonas aeruginosa . Combating Achromobacter biofilm can rely on antibiotics, particularly carbapenems, trimethoprim-sulfamethoxazole, and cefiderocol while some non-antibiotic approaches also show promising experimental antibiofilm activity.