Synergistic Anti-bacterial Effects of Phellinus baumii Ethyl Acetate Extracts and β-Lactam Antimicrobial Agents Against Methicillin-Resistant Staphylococcus aureus

INTRODUCTION: Methicillin-resistant Staphylococcus aureus (MRSA) is spread out in hospitals across different regions of the world and is regarded as the major agent of nosocomial infections, causing infections such as skin and soft tissue pneumonia and sepsis. The aim of this study was to identify risk factors for methicillin-resistance in Staphylococcus aureus bloodstream infection (BSI) and the predictive factors for death. METHODS: A retrospective cohort of fifty-one patients presenting bacteraemia due to S. aureus between September 2006 and September 2008 was analysed. Staphylococcu aureus samples were obtained from blood cultures performed by clinical hospital microbiology laboratory from the Uberlândia Federal University. Methicillinresistance was determined by growth on oxacillin screen agar and antimicrobial susceptibility by means of the disk diffusion method. RESULTS: We found similar numbers of MRSA (56.8%) and methicillin-susceptible Staphylococcus aureus (MSSA) (43.2%) infections, and the overall hospital mortality ratio was 47%, predominantly in MRSA group (70.8% vs. 29.2%) (p=0.05). Age (p=0.02) was significantly higher in MRSA patients as also was the use of central venous catheter (p=0.02). The use of two or more antimicrobial agents (p=0.03) and the length of hospital stay prior to bacteraemia superior to seven days (p=0.006) were associated with mortality. High odds ratio value was observed in cardiopathy as comorbidity. CONCLUSIONS: Despite several risk factors associated with MRSA and MSSA infection, the use of two or more antimicrobial agents was the unique independent variable associated with mortality.

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Antibacterial and anti-biofilm activities of crude extracts of Lawsonia inermis against Methicillin Resistant Staphylococcus aureus

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2016.v9i6.14362 ◽

2016 ◽

Vol 9 (6) ◽

pp. 263 ◽

Cited By ~ 1

Author(s):

Triveni A G ◽

Suresh Kumar Mendem ◽

Channapa T Shivannavar ◽

Subhaschandra M Gaddad

Keyword(s):

Staphylococcus Aureus ◽

Antibacterial Activity ◽

Ethyl Acetate ◽

Petroleum Ether ◽

Methicillin Resistant Staphylococcus Aureus ◽

Multi Drug Resistance ◽

Lawsonia Inermis ◽

Biofilm Inhibition ◽

Methicillin Resistant ◽

Crude Extracts

Objective:The continuous rise in the prevalence of multi drug resistance pathogens globally is threatening the treatment and management of infectious diseases. Ethno medicine plays a key role in the exploration for novel bioactive compounds. The present study evaluates the antibacterial and antibiofilm activities of the crude extracts of Lawsonia inermis against clinical isolates of methicillin resistant Staphylococcus aureus (MRSA).Materials and methods: Shade dried and finely powdered leaves of the plant were extracted by maceration method using six solvents methanol, acetone, ethyl acetate, chloroform, petroleum ether and n-hexane. Antibacterial and antibiofilm activities of the extracts against MDR MRSA by agar cup diffusion and tube method respectively.Results: Methanol extract showed the highest antibacterial activity of 18mm compared to other extracts. Similarly, petroleum ether extract showed highest biofilm inhibition of 84.7%. Other solvent extracts also exhibited significant biofilm inhibition [n-Hexane-83.6%, Ethyl acetate -79.5%, Chloroform-79.2%, Acetone -77% and Methanol-77%].Conclusion: The leaf extracts of L. inermis have shown promising biofilm inhibitory activity and good antibacterial activity, which can be explored for the development of new drugs for the MDR pathogens. Keywords: Antibioticacivity, Antibiofilm activity, L.inermis, MRSA

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The Frequency of Methicillin-Resistant Staphylococcus aureus and Coagulase Gene Polymorphism in Egypt

International Journal of Bacteriology ◽

10.1155/2014/680983 ◽

2014 ◽

Vol 2014 ◽

pp. 1-6 ◽

Cited By ~ 8

Author(s):

Hend M. Abdulghany ◽

Rasha M. Khairy

Keyword(s):

Staphylococcus Aureus ◽

Gene Polymorphism ◽

Antimicrobial Susceptibility ◽

Antimicrobial Agents ◽

Methicillin Resistant Staphylococcus Aureus ◽

Susceptibility Testing ◽

Antimicrobial Susceptibility Testing ◽

Methicillin Resistant ◽

Microbiological Methods ◽

Rflp Typing

The current study aimed to use Coagulase gene polymorphism to identify methicillin-resistant Staphylococcus aureus (MRSA) subtypes isolated from nasal carriers in Minia governorate, Egypt, evaluate the efficiency of these methods in discriminating variable strains, and compare these subtypes with antibiotypes. A total of 400 specimens were collected from nasal carriers in Minia governorate, Egypt, between March 2012 and April 2013. Fifty-eight strains (14.5%) were isolated and identified by standard microbiological methods as MRSA. The identified isolates were tested by Coagulase gene RFLP typing. Out of 58 MRSA isolates 15 coa types were classified, and the amplification products showed multiple bands (1, 2, 3, 4, 5, and 8 bands). Coagulase gene PCR-RFLPs exhibited 10 patterns that ranged from 1 to 8 fragments with AluI digestion. Antimicrobial susceptibility testing with a panel of 8 antimicrobial agents showed 6 different antibiotypes. Antibiotype 1 was the most common phenotype with 82.7%. The results have demonstrated that many new variants of the coa gene are present in Minia, Egypt, different from those reported in the previous studies. So surveillance of MRSA should be continued.

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In vitro Activity of Some Antimicrobial Agents against Staphylococcus aureus and Methicillin-Resistant Staphylococcus aureus in Khartoum, Sudan

Research Journal of Microbiology ◽

10.3923/jm.2009.366.369 ◽

2009 ◽

Vol 4 (10) ◽

pp. 366-369 ◽

Cited By ~ 3

Author(s):

H.A. Saeed ◽

W.B. Ahmed

Keyword(s):

Staphylococcus Aureus ◽

Antimicrobial Agents ◽

Methicillin Resistant Staphylococcus Aureus ◽

Vitro Activity ◽

In Vitro Activity ◽

Methicillin Resistant

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Novel Antibiotic Combinations of Diverse Subclasses for Effective Suppression of Extensively Drug-Resistant Methicillin-Resistant Staphylococcus aureus (MRSA)

International Journal of Microbiology ◽

10.1155/2020/8831322 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Shumyila Nasir ◽

Muhammad Sufyan Vohra ◽

Danish Gul ◽

Umm E Swaiba ◽

Maira Aleem ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Clavulanic Acid ◽

Antimicrobial Agents ◽

Methicillin Resistant Staphylococcus Aureus ◽

Multidrug Resistant ◽

Methicillin Resistant ◽

Development Of Resistance ◽

Amoxicillin Clavulanic Acid ◽

Combination Antibiotics ◽

Time Kill

The emergence of multidrug-resistant pathogens such as methicillin-resistant Staphylococcus aureus (MRSA), the chief etiological agent for a range of refractory infections, has rendered all β-lactams ineffective against it. The treatment process is further complicated with the development of resistance to glycopeptides, primary antibiotics for treatment of MRSA. Antibiotic combination therapy with existing antimicrobial agents may provide an immediate treatment option. Minimum inhibitory concentrations (MICs) of 18 different commercially available antibiotics were determined along with their 90 possible pairwise combinations and 64 triple combinations to filter out 5 best combinations. Time-Kill kinetics of these combinations were then analyzed to find collateral bactericidal combinations which were then tested on other randomly selected MRSA isolates. Among the top 5 combinations including levofloxacin-ceftazidime; amoxicillin/clavulanic acid-tobramycin; amoxicillin/clavulanic acid-cephradine; amoxicillin/clavulanic acid-ofloxacin; and piperacillin/tazobactam-tobramycin, three combinations were found to be collaterally effective. Levofloxacin-ceftazidime acted synergistically in 80% of the tested clinical MRSA isolates. First-line β-lactams of lower generations can be used effectively against MRSA infection when used in combination. Antibiotics other than glycopeptides may still work in combination.

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Promising Antibiofilm Agents: Recent Breakthrough against Biofilm Producing Methicillin-Resistant Staphylococcus aureus

Antibiotics ◽

10.3390/antibiotics9100667 ◽

2020 ◽

Vol 9 (10) ◽

pp. 667 ◽

Cited By ~ 2

Author(s):

Marwa I. Abd El-Hamid ◽

El-sayed Y. El-Naenaeey ◽

Toka M kandeel ◽

Wael A. H. Hegazy ◽

Rasha A. Mosbah ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Antimicrobial Agents ◽

Methicillin Resistant Staphylococcus Aureus ◽

Multidrug Resistant ◽

Antimicrobial Activities ◽

Proteinase K ◽

Zno Nps ◽

Methicillin Resistant ◽

Biofilm Production ◽

Antibiofilm Agents

Multidrug resistant (MDR) methicillin-resistant Staphylococcus aureus (MRSA) is a superbug pathogen that causes serious diseases. One of the main reasons for the lack of the effectiveness of antibiotic therapy against infections caused by this resistant pathogen is the recalcitrant nature of MRSA biofilms, which results in an increasingly serious situation worldwide. Consequently, the development of innovative biofilm inhibitors is urgently needed to control the biofilm formation by this pathogen. In this work, we thus sought to evaluate the biofilm inhibiting ability of some promising antibiofilm agents such as zinc oxide nanoparticles (Zno NPs), proteinase K, and hamamelitannin (HAM) in managing the MRSA biofilms. Different phenotypic and genotypic methods were used to identify the biofilm producing MDR MRSA isolates and the antibiofilm/antimicrobial activities of the used promising agents. Our study demonstrated strong antibiofilm activities of ZnO NPs, proteinase K, and HAM against MRSA biofilms along with their transcriptional modulation of biofilm (intercellular adhesion A, icaA) and quorum sensing (QS) (agr) genes. Interestingly, only ZnO NPs showed a powerful antimicrobial activity against this pathogen. Collectively, we observed overall positive correlations between the biofilm production and the antimicrobial resistance/agr genotypes II and IV. Meanwhile, there was no significant correlation between the toxin genes and the biofilm production. The ZnO NPs were recommended to be used alone as potent antimicrobial and antibiofilm agents against MDR MRSA and their biofilm-associated diseases. On the other hand, proteinase-K and HAM can be co-administrated with other antimicrobial agents to manage such types of infections.

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Genetic Characterization of Methicillin-Resistant Staphylococcus aureus Isolates from Human Bloodstream Infections: Detection of MLSB Resistance

Antibiotics ◽

10.3390/antibiotics9070375 ◽

2020 ◽

Vol 9 (7) ◽

pp. 375

Author(s):

Vanessa Silva ◽

Sara Hermenegildo ◽

Catarina Ferreira ◽

Célia M. Manaia ◽

Rosa Capita ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Antimicrobial Agents ◽

Methicillin Resistant Staphylococcus Aureus ◽

Bloodstream Infections ◽

Disk Diffusion ◽

Diffusion Method ◽

Accessory Gene ◽

Spa Typing ◽

Disk Diffusion Method ◽

Methicillin Resistant

In this study we aimed to characterize antimicrobial resistance in methicillin-resistant Staphylococcus aureus (MRSA) isolated from bloodstream infections as well as the associated genetic lineages of the isolates. Sixteen MRSA isolates were recovered from bacteremia samples from inpatients between 2016 and 2019. The antimicrobial susceptibility of these isolates was tested by the Kirby–Bauer disk diffusion method against 14 antimicrobial agents. To determine the macrolide–lincosamide–streptogramin B (MLSB) resistance phenotype of the isolates, erythromycin-resistant isolates were assessed by double-disk diffusion (D-test). The resistance and virulence genes were screened by polymerase chain reaction (PCR). All isolates were characterized by multilocus sequence typing (MLST), spa typing, staphylococcal chromosomal cassette mec (SCCmec) typing, and accessory gene regulator (agr) typing. Isolates showed resistance to cefoxitin, penicillin, ciprofloxacin, erythromycin, fusidic acid, clindamycin, and aminoglycosides, confirmed by the presence of the blaZ, ermA, ermC, mphC, msrA/B, aac(6’)-Ie-aph(2’’)-Ia, and ant(4’)-Ia genes. Three isolates were Panton–Valentine-leukocidin-positive. Most strains (n = 12) presented an inducible MLSB phenotype. The isolates were ascribed to eight spa-types (t747, t002, t020, t1084, t008, t10682, t18526, and t1370) and four MLSTs (ST22, ST5, ST105, and ST8). Overall, most (n = 12) MRSA isolates had a multidrug-resistance profile with inducible MLSB phenotypes and belonged to epidemic MRSA clones.

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