Assessment of different methods for the detection of biofilm production in coagulase-negative staphylococci isolated from blood cultures of newborns

Rampelotto, Roberta Filipini; Lorenzoni, Vinícius Victor; Silva, Danielly da Costa; Coelho, Silvana Silveira; Wust, Vanessa; Garzon, Litiérri Razia; Nunes, Melise Silveira; Meneghetti, Bettina; Brites, Patrícia Chaves; Hörner, Manfredo; Hörner, Rosmari

doi:10.1590/0037-8682-0171-2018

Cited by 10 publications

(4 citation statements)

References 33 publications

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“…Coagulase-negative staphylococci (CoNS) are the most abundant common microbial species of the human skin and mucous membranes, and they are one of the major health care-associated opportunistic pathogens [1, 2]. CoNS can easily attach and grow on the surface of medical devices through a slime layer that has a muco-polysaccharide structure [3–5]. CoNS may cause bacteraemia when medical devices penetrate the skin and the mucous membrane barrier and enter the blood [6].…”

Section: Introductionmentioning

confidence: 99%

The species distribution, antimicrobial resistance and risk factors for poor outcome of coagulase-negative staphylococci bacteraemia in China

Cui

Liang

et al. 2019

Antimicrob Resist Infect Control

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Objective Coagulase-negative staphylococci (CoNS) are one of the major opportunistic pathogens and the incidence of CoNS bacteraemia is increasing. However, most of the CoNS-positive blood cultures are contaminants rather than true CoNS bacteraemia. In order to minimize contamination, we defined true CoNS bacteraemia as the patient that has two or more identical CoNS-positive blood cultures drawn within 48 h in this study and the objective of this study was to analyse the species distribution and antibiotic resistance and to identify risk factors for 30-day mortality of the true CoNS-bacteraemia. Method By reviewing the electronic medical database, this study retrospectively analysed patients diagnosed as CoNS bacteraemia by blood cultures in a comprehensive tertiary care hospital in China from January 1, 2014, to December 31, 2017. Result A total of 1241 patients with 1562 episodes of CoNS-positive blood cultures were recorded in the database but only 157 patients were finally diagnosed as true CoNS bacteraemia after contaminants were excluded. All these 157 patients (12.7%, 157/1241) had bacteraemia-related clinical symptoms. Among the 157 patients, the most common species were Staphylococcus hominis (40.8%), Staphylococcus epidermidis (36.3%) and Staphylococcus capitis (11.5%). The antimicrobial susceptibility tests showed that all CoNS had a high rate of resistance to penicillin (94.9%), oxacillin (93.6%) and erythromycin (92.4%). Resistance to gentamicin (22.3%) and rifampicin (10.8%) was low, and none of the bacteria were resistant to vancomycin or linezolid. The 30-day mortality of patients with CoNS bacteraemia was up to 12.7% (20/157), and the multivariate logistics regression analysis showed that chronic renal failure (OR 5.9, 95% CI 1.6–21.5, p = 0.007) and chronic liver failure (OR 4.0, 95% CI 1.2–13.1, p = 0.024) were both the significant independent risk factors for the 30-day mortality of CoNS bacteraemia. Conclusion Staphylococcus hominis and Staphylococcus epidermidis were the most common species in CoNS bacteraemia. All CoNS had high multi-drug resistance, but gentamicin and rifampicin had a relatively lower resistance and could be considered as alternative antibiotics for anti-CoNS bacteraemia in addition to vancomycin and linezolid. Additionally, patients with chronic renal failure or chronic liver failure have a higher 30-day mortality after the onset of CoNS bacteraemia.

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Section: Introductionmentioning

confidence: 99%

The species distribution, antimicrobial resistance and risk factors for poor outcome of coagulase-negative staphylococci bacteraemia in China

Cui

Liang

et al. 2019

Antimicrob Resist Infect Control

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“…By Congo red agar (CRA) assay, slime-producing bacteria in a report by Freeman et al and biofilm-producing bacteria in a report by Rampelotto et al showed black colonies. By contrast, colonies of non-slime-/biofilm-producing isolates remained pink/red [34,40]. The K. pneumoniae STU1 wild-type and crr complemented strain on plates containing Congo red revealed gray colonies, while the crr mutant displayed black colonies, indicating that all of strains (wild-type, crr complemented strain and crr mutant) produced glycocalyx but the crr mutant may have more glycocalyx ( Figure 3B).…”

Section: Crr An Eiia Component Reduces Cps Synthesis In K Pneumonimentioning

confidence: 99%

“…Bacteria were observed according to the method described by Rampelotto et al with modification [34]. In brief, overnight bacterial cultures in LB were washed twice with phosphate-buffered saline (PBS) and then adjusted to an OD 600 of 0.001.…”

Section: Congo Red Agar (Cra) Assaymentioning

confidence: 99%

The PTS Components in Klebsiella pneumoniae Affect Bacterial Capsular Polysaccharide Production and Macrophage Phagocytosis Resistance

et al. 2021

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Capsular polysaccharide (CPS) is a crucial virulence factor for Klebsiella pneumoniae infection. We demonstrated an association of CPS production with two phosphoenolpyruvate:carbohydrate phosphotransferase systems (PTSs). Deficiency of crr, encoding enzyme IIA of PTS, in K. pneumoniae enhanced the transcriptional activities of galF, wzi and gnd, which are in the cps gene cluster, leading to high CPS production. A crr mutant exhibited a higher survival rate in 1% hydrogen peroxide than the wild-type. The crr mutant showed less sensitivity to engulfment by macrophage (RAW 264.7) than the wild-type by observing the intracellular bacteria using confocal laser scanning microscopy (CLSM) and by calculating the colony-forming units (CFU) of intracellular bacteria. After long-term incubation, the survival rate of the intracellular crr mutant was higher than that of the wild-type. Deficiency of crr enhanced the transcriptional activities of etcABC which encodes another putative enzyme II complex of a PTS. Deletion of etcABC in the crr mutant reduced CPS production and the transcriptional activities of galF compared to those of the crr mutant. These results indicated that one PTS component, Crr, represses CPS production by repressing another PTS component, EtcABC, in K. pneumoniae. In addition, PTS plays a role in bacterial resistance to macrophage phagocytosis.

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“…These bacteria take part in the formation of periodontal (gingival) pocket, destruction of the connective tissue, alveolar bone resorption (alveoloclasia), etc. The formation of inflammatory infiltrate is accompanied by various immunopathologies [4,6,20].…”

Section: Introductionmentioning

confidence: 99%

Determination of biofilm formation and associated gene detection in Staphylococcus genus isolated from the oral cavity under inflammatory periodontal diseases

Kryvtsov¹,

Microbiology²,

Király³

et al. 2020

Biol. Stud.

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Background. Inflammatory periodontal diseases, including chronic periodontitis, are accompanied by a chronic persisting inflammatory process. The latter process and biofilm-forming potential are the factors that contribute to the formation of antibiotic-resistant microorganism strains. The purpose of our work was to study the biofilm-forming ability of antibiotic-resistant biofilm-forming Staphylococcus genus bacteria isolated from the oral cavities of patients suffering from periodontitis, and check the presence of the genes associated with biofilm formation in these bacteria. Material and methods. Isolates were obtained from patients suffering from chronic periodontitis using differentially diagnostic nutrient media. Chemotaxonomic identification of the antibiotic-resistant isolates was performed on the Microflex LT device. Biofilm-forming potential was studied in plastic Petri dishes by spectrophotometric method. The antibiotic sensitivity of the bacteria and microscopic fungi was identified by the disc diffusion method. The presence of icaA, icaD, icaC, icaB, agrA, srtA genes was detected in two multiplex polymerase chain reactions (mPCR). 16S rRNA gene and icaR genes were amplified in a separate PCR. Results. Opportunistic microbial associations dominate in the microbiom of the oral cavity under conditions of periodontitis; besides, in the majority of cases, Staphylococcus genus bacteria were present in associations. In 73 % (131/180) of cases, bacte ria from Staphylococcus genus represented by six species-S. aureus, S. haemolyticus, S. saprophyticus, S. epidermidis, S. xelosus, and S. hominis were isolated from the nidus during the inflammatory process. From the oral cavities of the patients with inflammatory periodontitis, 51 biofilm-forming strains of S. aureus, 29 strains of S. haemolyticus, 12 strains of S. saprophyticus, and 12 strains of S. epidermidis were isolated. It was established that antibiotic-resistant isolates of S. aureus possess the genetic determinants which are now believed to be connected with icaA, icaC, icaB icaA, icaR, agrA, and srtA biofilm-forming potential. Two non-biofilm forming strains of S. aureus were proven to lack the genes responsible for the biofilm-forming ability. Conclusion: It has been established that microbial associations with a prevailing share of Staphylococcus genus bacteria, most of which have a biofilm-forming potential, dominate in the microbiom of the oral cavity under conditions of periodontitis.

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Assessment of different methods for the detection of biofilm production in coagulase-negative staphylococci isolated from blood cultures of newborns

Cited by 10 publications

References 33 publications

The species distribution, antimicrobial resistance and risk factors for poor outcome of coagulase-negative staphylococci bacteraemia in China

The species distribution, antimicrobial resistance and risk factors for poor outcome of coagulase-negative staphylococci bacteraemia in China

The PTS Components in Klebsiella pneumoniae Affect Bacterial Capsular Polysaccharide Production and Macrophage Phagocytosis Resistance

Determination of biofilm formation and associated gene detection in Staphylococcus genus isolated from the oral cavity under inflammatory periodontal diseases

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