Bacillus cereus biofilm formation on central venous catheters of hospitalised cardiac patients

Abstract

Formation of bacterial biofilms is a risk with many in situ medical devices. Biofilm-forming Bacillus species are associated with potentially life-threatening catheter-related blood stream infections in immunocompromised patients. Here, bacteria were isolated from biofilm-like structures within the lumen of central venous catheters (CVCs) from two patients admitted to cardiac hospital wards. Isolates belonged to the Bacillus cereus group, exhibited strong biofilm formation propensity, and mapped phylogenetically close to the B. cereus emetic cluster. Together, whole genome sequencing and quantitative PCR confirmed that the isolates constituted the same strain and possessed a range of genes important for and up-regulated during biofilm formation. Antimicrobial susceptibility testing demonstrated resistance to trimethoprim-sulphamethoxazole, clindamycin, penicillin and ampicillin. Inspection of the genome revealed several chromosomal b-lactamase genes and a sulphonamide resistant variant of folP. This study clearly shows that B. cereus persisting in hospital ward environments may constitute a risk factor from repeated contamination of CVCs. ARTICLE HISTORY

Assessment and molecular characterization of Bacillus cereus isolated from edible fungi in China

“…However, their isolates were fully sensitive to chloramphenicol, gentamicin, imipenem, sulfamethoxazole, and tetracycline [54], whereas 22.7% of our isolates showed resistance to sulfamethoxazole. Luna et al [55] and Ikram et al [56] had reported B. cereus to be resistant to ampicillin, penicillin, and sensitive to chloramphenicol, ciprofloxacin, and gentamicin, similar to our findings; however, 72.1% of our isolates showed intermediate resistance to quinupristindalfopristin and 91.1% of our isolates showed resistance to rifampin. These differences may be caused by the differences in sample sources, and sampling sites.…”

Antimicrobial Susceptibility Profile and Whole-Genome Analysis of a Strong Biofilm-Forming Bacillus Sp. B87 Strain Isolated from Food

“…Moreover, biofilm formation allows the development and transfer of antimicrobial resistance through the bacterial interactions that occur within the biofilm [10,11]. The key genes for biofilm formation comprise those encoding biofilm transcriptional regulators, matrix structural genes, potential extracellular DNA synthesis genes, and cyclic-di-GMP metabolism genes [12]. In addition, several gene loci are involved in biofilm formation, including genes encoding the lipopeptide kurstakin, genes encoding the cyclic-di-GMP responsive effector protein BspA, and genes encoding the c-di-GMP synthesizing enzyme [13][14][15][16].…”

Cell adhesion in microchannel multiple constrictions – Evidence of mass transport limitations

“…In these devices, the formation of a microbial biofilm can originate serious problems to the patient health (e.g. urinary and catheter-related bloodstream infections [13,14], implant failure [15]), beyond this, it can also compromise the lifespan of the often require complex geometries [16][17][18][19][20][21][22]. However, these complex geometries and the associated flow variations increase the probability and the available area for bacterial attachment.…”