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Iranian Biomedical Journal Jul 2016The aim of this study was to compare the biofilm formation and the prevalence of biofilm-associated genes between the isolates of methicillin-resistant (MRSA) and... (Comparative Study)
Comparative Study
BACKGROUND
The aim of this study was to compare the biofilm formation and the prevalence of biofilm-associated genes between the isolates of methicillin-resistant (MRSA) and methicillin-susceptible (MSSA) Staphylococcus aureus.
METHODS
In total, 209 S. aureus isolates were collected. The antibiotic susceptibility test was conducted using nine antibiotics according to the guidelines of Clinical and Laboratory Standards Institute. Phenotypic biofilm formation was performed with microtiter plate assay. The polymerase chain reaction was employed to detect icaA, icaD, icaB, icaC, clfA, clfB, fnbA, fnbB, fib, cna, eno, ebps, bbp, mecA, and SCCmec types as well as agr group genes with specific primers.
RESULTS
Sixty-four (30.62%) isolates were resistant to methicillin, and 54 (83%) MRSA harbored SCCmec III. Furthermore, 122 (58.3%) isolates belonged to agr group I. Twenty-six (36.1%) MRSA and 42 (28.9%) MSSA isolates were strong biofilm producers (no significant difference). The prevalence of icaA, icaD, icaB, and icaC genes in MSSA isolates was 71, 41, 76, and 72%, respectively. The frequency of clfA, clfB, fnbA, fnbB, fib, cna, eno, ebps, and bbp in MSSA was 100, 100, 56, 46, 74, 54, 78, 11, and 1%, respectively. However, in MRSA isolates, the frequency was 97, 97, 64, 51, 76, 56, 79, and 12% with no track of bbp, respectively.
CONCLUSION
Statistical difference between MSSA and MRSA regarding biofilm formation and the frequency of all biofilm-encoding genes was not significant. The majority of the S. aureus isolates harbored clfA, clfB, eno, fib, icaA, and icaD genes.
Topics: Anti-Bacterial Agents; Biofilms; Methicillin; Methicillin Resistance; Methicillin-Resistant Staphylococcus aureus; Microbial Sensitivity Tests; Polymerase Chain Reaction
PubMed: 26948126
DOI: 10.7508/ibj.2016.03.007 -
Microbiology Spectrum Aug 2023Methicillin-resistant Staphylococcus aureus (MRSA) is a clinical threat with high morbidity and mortality. Here, we describe a new simple, rapid identification method...
Methicillin-resistant Staphylococcus aureus (MRSA) is a clinical threat with high morbidity and mortality. Here, we describe a new simple, rapid identification method for MRSA using oxacillin sodium salt, a cell wall synthesis inhibitor, combined with Gram staining and machine vision (MV) analysis. Gram staining classifies bacteria as positive (purple) or negative (pink) according to the cell wall structure and chemical composition. In the presence of oxacillin, the integrity of the cell wall for methicillin-susceptible S. aureus (MSSA) was destroyed immediately and appeared Gram negative. In contrast, MRSA was relatively stable and appeared Gram positive. This color change can be detected by MV. The feasibility of this method was demonstrated in 150 images of the staining results for 50 clinical S. aureus strains. Based on effective feature extraction and machine learning, the accuracies of the linear linear discriminant analysis (LDA) model and nonlinear artificial neural network (ANN) model for MRSA identification were 96.7% and 97.3%, respectively. Combined with MV analysis, this simple strategy improved the detection efficiency and significantly shortened the time needed to detect antibiotic resistance. The whole process can be completed within 1 h. Unlike the traditional antibiotic susceptibility test, overnight incubation is avoided. This new strategy could be used for other bacteria and represents a new rapid method for detection of clinical antibiotic resistance. Oxacillin sodium salt destroys the integrity of the cell wall of MSSA immediately, appearing Gram negative, whereas MRSA is relatively stable and still appears Gram positive. This color change can be detected by microscopic examination and MV analysis. This new strategy has significantly reduced the time to detect resistance. The results show that using oxacillin sodium salt combined with Gram staining and MV analysis is a new, simple and rapid method for identification of MRSA.
Topics: Humans; Methicillin-Resistant Staphylococcus aureus; Staphylococcus aureus; Microbial Sensitivity Tests; Oxacillin; Methicillin; Staining and Labeling; Anti-Bacterial Agents; Staphylococcal Infections
PubMed: 37395643
DOI: 10.1128/spectrum.05282-22 -
Poultry Science Oct 2022Colonization of food-producing animals by antimicrobial-resistant Staphylococcus aureus, especially methicillin-resistant S. aureus (MRSA), has become a serious public...
Clonal distribution and antimicrobial resistance of methicillin-susceptible and -resistant Staphylococcus aureus strains isolated from broiler farms, slaughterhouses, and retail chicken meat.
Colonization of food-producing animals by antimicrobial-resistant Staphylococcus aureus, especially methicillin-resistant S. aureus (MRSA), has become a serious public health problem worldwide. In the current study, clonal diversities of livestock-associated S. aureus isolates collected from broiler farms, slaughterhouses, and retail chicken meat were examined. Two-hundred S. aureus isolates (43 MRSA and 157 methicillin-susceptible S. aureus [MSSA] isolates) were analyzed to determine 1) the genotypes of the isolates (multilocus sequence, agr, and spa types), 2) the methicillin resistance phenotype and staphylococcal cassette chromosome mec (SCCmec) types, 3) the antimicrobial resistance profiles, and 4) the mutational changes in gyrA, gyrB, parC, and parE in fluoroquinolone-resistant isolates. Fifteen different sequence types (STs) of MSSA strains displaying a relatively high degree of genetic diversity were detected in broiler farms, slaughterhouses, and retail chicken meat. In contrast to MSSA, 2 dominant genetic lineages of MRSA (ST692-SCCmecV with t2249 spa type, and ST188-SCCmecIVa with spa type t189) were found in healthy broilers. The high prevalence of ST692 and ST188 in healthy broilers is associated with high levels of multiple antimicrobial-resistance phenotypes, particularly fluoroquinolone resistance. All fluoroquinolone-resistant isolates carried double point mutations in gyrA (S84L) and parC (S80F), regardless of STs or methicillin resistance. Notably, only the ST188 lineage carried an additional third mutation in gyrB (D494N), correlating with enhanced ciprofloxacin minimum inhibitory concentration values versus the strains with double mutations. These results provide important insights into the genetic diversity of antimicrobial-resistant S. aureus strains associated with the chicken meat production chain, including healthy broilers, in Korea.
Topics: Abattoirs; Animals; Anti-Bacterial Agents; Chickens; Ciprofloxacin; Drug Resistance, Bacterial; Farms; Fluoroquinolones; Genotype; Meat; Methicillin; Methicillin-Resistant Staphylococcus aureus; Microbial Sensitivity Tests; Staphylococcal Infections; Staphylococcus aureus
PubMed: 36041389
DOI: 10.1016/j.psj.2022.102070 -
JPMA. the Journal of the Pakistan... Apr 2023To characterise the biofilm matrix composition of a newly described Staphylococcus aureus biofilm phenotype.
OBJECTIVES
To characterise the biofilm matrix composition of a newly described Staphylococcus aureus biofilm phenotype.
METHOD
This experimental study was conducted at the Faculty of Pharmacy, Helwan University, Cairo, Egypt, from January 2021 to March 2022, and comprised methicillin-resistant Staphylococcus aureus and methicillin-susceptible Staphylococcus aureus biofilm-forming clinical isolates which were allowed to construct biofilms under two distinct culture conditions; one a commonly used condition, and the other one a novel, more biologically-relevant condition. The formed biofilms were analysed for matrix composition through treatment with proteinase,sodium meta-periodate, and streptokinase. The efficacy of Cis-2-Decenoic acid and hamamelitannin on the biologically-relevant biofilms was evaluated using biofilm viability assay based on a colorimetric assay for measuring cell metabolic activity and scanning electron microscope imaging. Data was analysed using GraphPad Prism 5.01.
RESULTS
Of the 58 isolates, 45(77.6%) were methicillin-resistant Staphylococcus aureus and 13(22.4%) were methicillin susceptible Staphylococcus aureus. There was significant difference in responses to streptokinase, proteinase and sodium meta-periodate (p<0.05) among the differentially-developed biofilms in methicillin-resistant Staphylococcus aureus isolates. Regarding the methicillin-susceptible Staphylococcus aureus isolates, the differentially-developed biofilms showed significantly different liabilities to streptokinase only (p<0.05). Mean biofilm inhibition for Cis-2- Decenoic acid was 54.27±27.93% and mean biofilm dispersion was 71.92±11.59% while the corresponding valuesfor hamamelitannin were 83.03±13.95% and 70.48±7.116% against the newly described methicillin-resistant Staphylococcus aureus biofilm phenotype.
CONCLUSIONS
Applying biologically-relevant culture conditions on staphylococci biofilms and antibiofilm drugs is recommended.
Topics: Humans; Staphylococcus aureus; Methicillin-Resistant Staphylococcus aureus; Methicillin; Anti-Bacterial Agents; Staphylococcal Infections; Biofilms; Peptide Hydrolases; Phenotype; Streptokinase; Sodium; Microbial Sensitivity Tests
PubMed: 37482852
DOI: 10.47391/JPMA.EGY-S4-34 -
Antibiotics (Basel, Switzerland) Aug 2022Combination therapy with daptomycin plus ceftaroline to treat methicillin-resistant bacteremia has been reported to reduce methicillin-resistant bacteremia-related... (Review)
Review
Comparing the Outcomes of Ceftaroline plus Vancomycin or Daptomycin Combination Therapy versus Vancomycin or Daptomycin Monotherapy in Adults with Methicillin-Resistant Bacteremia-A Meta-Analysis.
INTRODUCTION
Combination therapy with daptomycin plus ceftaroline to treat methicillin-resistant bacteremia has been reported to reduce methicillin-resistant bacteremia-related mortality. The purpose of the current meta-analysis was to compare the clinical outcome of methicillin-resistant bacteremia in patients treated with daptomycin or vancomycin plus ceftaroline combination therapy versus daptomycin or vancomycin monotherapy.
METHODS
Studies were included if they directly compared the efficacy of daptomycin or vancomycin plus ceftaroline combination therapy with that of daptomycin or vancomycin monotherapy in the treatment of methicillin-resistant bacteremia in adult patients.
RESULTS
One randomized controlled trial and five retrospective studies were included in the meta-analysis. The combination therapy group had an in-hospital mortality, duration of bacteremia, and adverse event rate similar to those patients who had monotherapy. There was less bacteremia recurrence in the combination group. Initial combination therapy with ceftaroline for the treatment of methicillin-resistant bacteremia showed a trend of reducing the risk of in-hospital mortality in the current meta-analysis.
CONCLUSIONS
Randomized controlled trials are needed to further study the role of initial combination therapy with daptomycin or vancomycin plus ceftaroline in the treatment of methicillin-resistant bacteremia.
PubMed: 36009973
DOI: 10.3390/antibiotics11081104 -
Biomedica : Revista Del Instituto... Sep 2019Introduction: Infections associated with health care caused by S. aureus and coagulase-negative Staphylococci multi-resistant to antibiotics cause a high epidemiological...
Introduction: Infections associated with health care caused by S. aureus and coagulase-negative Staphylococci multi-resistant to antibiotics cause a high epidemiological impact due to their high morbidity and mortality. Biofilm formation, which has been associated with antimicrobial resistance, can also occur. Objectives: To determine methicillin resistance and to quantify the biofilm production to establish if there is a relationship in clinical isolates of S. aureus and coagulase-negative Staphylococci. Material and methods: A total of 11 strains of S. aureus and 12 of coagulase-negative Staphylococci were studied. Methicillin resistance was determined with cefoxitin discs and the Clinical Laboratory Standards Institute (CSLI), 2018 reference values. Biofilm production was quantified by the crystal violet method. The mecA and icaADBC genes were identified by PCR. A bivariate analysis was performed with chi-square (c2) and Cramér’s V statistical tests, using SPSS™, version 20.0 software. Results: Nine S. aureus strains were methicillin-resistant and two were sensitive. Eight coagulase-negative Staphylococci strains were resistant and four were sensitive. The mecA genotype was found in eight of the nine S. aureus resistant strains and six of eight resistant coagulase-negative Staphylococci. All strains formed biofilms. Ten strains of S. aureus and 11 of coagulase-negative Staphylococci presented the icaADCB genotype. No association was found between methicillin-resistance and biofilm formation. Conclusions: Cefoxitin is enough to define the resistance phenotype and is associated with the mecA genotype. All strains formed biofilms and were related to the presence of the icaADCB operon. Biofilm formation and methicillin resistance were independent features in both groups of strains.
Topics: Anti-Bacterial Agents; Bacterial Proteins; Biofilms; Cefoxitin; Coagulase; DNA, Bacterial; Genes, Bacterial; Humans; Methicillin Resistance; Methicillin-Resistant Staphylococcus aureus; Mexico; Microbial Sensitivity Tests; Oxacillin; Penicillin-Binding Proteins; Staphylococcal Infections; Staphylococcus; Staphylococcus aureus
PubMed: 31584765
DOI: 10.7705/biomedica.4131 -
Journal of Microbiology and... Dec 2022is a cause of high mortality in humans and therefore it is necessary to prevent its transmission and reduce infections. Our goals in this research were to investigate...
is a cause of high mortality in humans and therefore it is necessary to prevent its transmission and reduce infections. Our goals in this research were to investigate the frequency of methicillin-resistant (MRSA) in Taif, Saudi Arabia, and assess the relationship between the phenotypic antimicrobial sensitivity patterns and the genes responsible for resistance. In addition, we examined the antimicrobial efficiency and application of silver nanoparticles (AgNPs) against MRSA isolates. Seventy-two nasal swabs were taken from patients; MRSA was cultivated on Mannitol Salt Agar supplemented with methicillin, and 16S rRNA sequencing was conducted in addition to morphological and biochemical identification. Specific resistance genes such as , , , and were PCR-amplified and resistance plasmids were also investigated. The MRSA incidence was ~49 % among the 72 isolates and all MRSA strains were resistant to oxacillin, penicillin, and cefoxitin. However, vancomycin, linezolid, teicoplanin, mupirocin, and rifampicin were effective against 100% of MRSA strains. About 61% of MRSA strains exhibited multidrug resistance and were resistant to 3-12 antimicrobial medications (MDR). Methicillin resistance gene mecA was presented in all MDR-MRSA strains. Most MDR-MRSA contained a plasmid of > 10 kb. To overcome bacterial resistance, AgNPs were applied and displayed high antimicrobial activity and synergistic effect with penicillin. Our findings may help establish programs to control bacterial spread in communities as AgNPs appeared to exert a synergistic effect with penicillin to control bacterial resistance.
Topics: Humans; Methicillin-Resistant Staphylococcus aureus; Methicillin Resistance; Anti-Bacterial Agents; Staphylococcus aureus; Silver; Prevalence; Metal Nanoparticles; RNA, Ribosomal, 16S; Bacterial Proteins; Penicillin-Binding Proteins; Microbial Sensitivity Tests; Methicillin; Staphylococcal Infections
PubMed: 36379700
DOI: 10.4014/jmb.2208.08004 -
Applied Microbiology and Biotechnology Feb 2023Staphylococcus aureus biofilms are implicated in hospital infections due to elevated antibiotic and host immune system resistance. Molecular components of cell wall...
Staphylococcus aureus biofilms are implicated in hospital infections due to elevated antibiotic and host immune system resistance. Molecular components of cell wall including amyloid proteins, peptidoglycans (PGs), and lipoteichoic acid (LTA) are crucial for biofilm formation and tolerance of methicillin-resistant S. aureus (MRSA). Significance of alkaline phosphatases (ALPs) for biofilm formation has been recorded. Serrapeptase (SPT), a protease of Serratia marcescens, possesses antimicrobial properties similar or superior to those of many antibiotics. In the present study, SPT anti-biofilm activity was demonstrated against S. aureus (ATCC 25923, methicillin-susceptible strain, methicillin-susceptible S. aureus (MSSA)) and MRSA (ST80), with IC values of 0.67 μg/mL and 7.70 μg/mL, respectively. SPT affected bacterial viability, causing a maximum inhibition of - 46% and - 27%, respectively. Decreased PGs content at [SPT] ≥ 0.5 μg/mL and ≥ 8 μg/mL was verified for MSSA and MRSA, respectively. In MSSA, LTA levels decreased significantly (up to - 40%) at lower SPT doses but increased at the highest dose of 2 μg/mL, a counter to spectacularly increased cellular and secreted LTA levels in MRSA. SPT also reduced amyloids of both strains. Additionally, intracellular ALP activity decreased in both MSSA and MRSA (up to - 85% and - 89%, respectively), while extracellular activity increased up to + 482% in MSSA and + 267% in MRSA. Altered levels of DING proteins, which are involved in phosphate metabolism, in SPT-treated bacteria, were also demonstrated here, implying impaired phosphorus homeostasis. The differential alterations in the studied molecular aspects underline the differences between MSSA and MRSA and offer new insights in the treatment of resistant bacterial biofilms. KEY POINTS: • SPT inhibits biofilm formation in methicillin-resistant and methicillin-susceptible S. aureus. • SPT treatment decreases bacterial viability, ALP activity, and cell wall composition. • SPT-treated bacteria present altered levels of phosphate-related DING proteins.
Topics: Humans; Staphylococcus aureus; Methicillin-Resistant Staphylococcus aureus; Methicillin; Anti-Bacterial Agents; Peptide Hydrolases; Staphylococcal Infections; Biofilms; Homeostasis; Microbial Sensitivity Tests
PubMed: 36635396
DOI: 10.1007/s00253-022-12356-5 -
The Cochrane Database of Systematic... Jul 2018Cystic fibrosis is an inherited life-threatening multisystem disorder with lung disease characterized by abnormally thick airway secretions and persistent bacterial... (Review)
Review
BACKGROUND
Cystic fibrosis is an inherited life-threatening multisystem disorder with lung disease characterized by abnormally thick airway secretions and persistent bacterial infection. Chronic, progressive lung disease is the most important cause of morbidity and mortality in the condition and is therefore the main focus of clinical care and research. Staphylococcus aureus is a major cause of chest infection in people with cystic fibrosis. Early onset, as well as chronic, lung infection with this organism in young children and adults results in worsening lung function, poorer nutrition and increases the airway inflammatory response, thus leading to a poor overall clinical outcome. There are currently no evidence-based guidelines for chronic suppressive therapy for Staphylococcus aureus infection in cystic fibrosis such as those used for Pseudomonas aeruginosa infection. This is an update of a previously published review.
OBJECTIVES
To assess the evidence regarding the effectiveness of long-term antibiotic treatment regimens for chronic infection with methicillin-sensitive Staphylococcus aureus (MSSA) infection in people with cystic fibrosis and to determine whether this leads to improved clinical and microbiological outcomes.
SEARCH METHODS
Trials were identified by searching the Cochrane Cystic Fibrosis and Genetic Disorders Group's Cystic Fibrosis Trials Register, MEDLINE, Embase, handsearching article reference lists and through contact with local and international experts in the field. Date of the last search of the Group's Cystic Fibrosis Trials Register: 09 February 2018.We also searched ongoing trials databases. Date of latest search: 20 May 2018.
SELECTION CRITERIA
Randomised or quasi-randomised controlled trials comparing any combinations of topical, inhaled, oral or intravenous antimicrobials used as suppressive therapy for chronic infection with methicillin-sensitive Staphylococcus aureus compared with placebo or no treatment.
DATA COLLECTION AND ANALYSIS
The authors independently assessed all search results for eligibility. No eligible trials were identified.
MAIN RESULTS
The searches identified 58 trials, but none were eligible for inclusion in the current version of this review.
AUTHORS' CONCLUSIONS
No randomised controlled trials were identified which met the inclusion criteria for this review. Although methicillin-sensitive Staphylococcus aureus is an important and common cause of lung infection in people with cystic fibrosis, there is no agreement on how best to treat long-term infection. The review highlights the need to organise well-designed trials that can provide evidence to support the best management strategy for chronic methicillin-sensitive Staphylococcus aureus infection in people with cystic fibrosis.
Topics: Anti-Bacterial Agents; Cystic Fibrosis; Humans; Methicillin; Respiratory Tract Infections; Staphylococcal Infections; Staphylococcus aureus
PubMed: 30052271
DOI: 10.1002/14651858.CD011581.pub3 -
Toxins Jan 2020Rats are a reservoir of human- and livestock-associated methicillin-resistant (MRSA). However, the composition of the natural population in wild and laboratory rats is...
Rats are a reservoir of human- and livestock-associated methicillin-resistant (MRSA). However, the composition of the natural population in wild and laboratory rats is largely unknown. Here, 144 nasal isolates from free-living wild rats, captive wild rats and laboratory rats were genotyped and profiled for antibiotic resistances and human-specific virulence genes. The nasal carriage rate was higher among wild rats (23.4%) than laboratory rats (12.3%). Free-living wild rats were primarily colonized with isolates of clonal complex (CC) 49 and CC130 and maintained these strains even in husbandry. Moreover, upon livestock contact, CC398 isolates were acquired. In contrast, laboratory rats were colonized with many different lineages-many of which are commonly found in humans. Five captive wild rats were colonized with CC398-MRSA. Moreover, a single CC30-MRSA and two CC130-MRSA were detected in free-living or captive wild rats. Rat-derived isolates rarely harbored the phage-carried immune evasion gene cluster or superantigen genes, suggesting long-term adaptation to their host. Taken together, our study revealed a natural population in wild rats, as well as a colonization pressure on wild and laboratory rats by exposure to livestock- and human-associated , respectively.
Topics: Animals; Animals, Wild; Anti-Bacterial Agents; Blood Coagulation; Czech Republic; Ecosystem; Germany; Methicillin; Molecular Epidemiology; Nose; Rats, Sprague-Dawley; Staphylococcal Infections; Staphylococcus aureus; Virulence Factors
PubMed: 31991690
DOI: 10.3390/toxins12020080