The frequency of adherence, biofilm-associated, Arginine Catabolic Mobile element genes, and biofilm formation in clinical and healthcare worker coagulase-negative staphylococci isolates

Abstract

Background Healthcare workers may pave the way for increased infections in hospitalized patients by coagulase-negative staphylococci (CoNS). Biofilm formation and antibiotic resistance are the major problems posed by CoNS in nosocomial infections. In this study, we determined biofilm production level and the distribution of biofilm-associated and virulence genes, including icaADBC, aap, bhp, atlE, embp, and fbe, as well as IS256, IS257, mecA, and ACME clusters (arc-A, opp-3AB) among 114 clinical (n = 57) and healthcare workers (n = 57) CoNS isolates in Kerman, Iran. Results In this study, more than 80% (n = 96) of isolates were methicillin-resistant CoNS (MR-CoNS). Out of 114 isolates, 33% (n = 38) were strong biofilm producers. Strong biofilm formation was found to be significantly different between clinical and healthcare workers’ isolates (P < 0.050). In addition, 28% (n = 32) of isolates were positive for icaADBC simultaneously, and all were strong biofilm producers. The prevalence of icaADBC, mecA, bhp, fbe, and IS256 in clinical isolates was higher than that in healthcare workers’ isolates (P < 0.050). A significant relationship was observed between clinical isolates and the presence of icaADBC, mecA, bhp, and IS256. Although these elements were detected in healthcare workers’ isolates, they were more frequent in clinical isolates compared to those of healthcare workers. Conclusions The high prevalence of ACME clusters in healthcare workers’ isolates and biofilm formation of these isolates partially confirms the bacterial colonization in the skin of healthcare workers. Isolating MR-CoNS from healthcare workers’ skin through similar genetic elements to clinical isolates, such as icaADBC, mecA, and IS256, calls for appropriate strategies to control and prevent hospital infections.

Emergence of multidrug-resistant Staphylococcus haemolyticus in neonatal intensive care unit in Southern France, a genomic study

“…Considering ST29’s direct association with mortality in newborns, this high morbidity could be explained by the expression of virulence factors involved in immune evasion and anti-phagocytosis activity [ 48–52 ], as well as by biofilm formation-encoding genes predicted only in ST29 genomes. Moreover, the insertion sequence IS 257, related to CoNS virulence and biofilm formation [ 53 , 54 ] was identified in all S. haemolyticus genomes, but with ≥3 copies in ST29 genomes. The persistence and expansion of S. haemolyticus in the hospital environment are potentially due to efflux pumps such as bltR , cadD_2 , czcD, involved in multidrug release and heavy metals resistance [ 55 ], as well as the presence of rep5 and rep20 plasmids involved in methicillin resistance phenotype [ 56 ].…”