Investigating the relationship between carbapenemase production and biofilm formation in Klebsiella pneumoniae clinical isolates

Objective Carbapenemase production and biofilm formation in K. pneumoniae are crucial factors influencing the pathogenicity and antibiotic resistance of this bacterium. This study investigated the interplay between carbapenemase production and biofilm formation in K. pneumoniae clinical isolates. Results The distribution of biofilm-forming ability significantly differed between carbapenemase-producing (CP-Kp) (n = 52) isolates and carbapenemase-nonproducing (CN-Kp) isolates (n = 37), suggesting a potential link between carbapenemase production and biofilm formation. All the bla(NDM-1)-harbouring isolates demonstrated biofilm formation, with varying levels classified as strong (33.33%), moderate (22.22%), or weak (44.45%). bla(NDM-1) and bla(KPC)-coharbouring isolates did not exhibit strong or moderate biofilm formation. bla(NDM-1) and bla(OXA-48)-coharbouring isolates were predominantly moderate (48.65%), followed by weak (32.43%), with none showing strong biofilm production. These findings suggest a correlation between the presence of carbapenemases and biofilm-forming ability; however, the heterogeneity in biofilm-forming abilities associated with different carbapenemase types and the absence of strong biofilm producers in the detected carbapenemase combinations prompt a closer look at the complex regulatory mechanisms governing biofilm formation in CP-Kp isolates.