Reliability of the Kirby-Bauer Disc Diffusion Method for Detecting Methicillin-Resistant Strains of Staphylococcus aureus

Meticillin-resistant Staphylococcus aureus isolates were classified into three mupirocin susceptibility groups by the disc diffusion method using 5 and 200 μg mupirocin discs. The zone diameter observed for a 5 μg disc distinguished MupS from the resistant strains (either MupRL or MupRH). On the other hand, a 200 μg disc distinguished the high-resistance MupRH strains from the other two (MupS or MupRL). Thus, the concomitant use of 5 and 200 μg mupirocin discs allowed the clear distinction among the three mupirocin susceptibility groups, MupS, MupRL or MupRH.

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PERFORMANCE OF CHROM AGAR MEDIUM AND CONVENTIONAL METHODS FOR DETECTION OF METHICILLIN RESISTANT STAPHYLOCOCCUS AUREUS.

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2016.v9i6.13916 ◽

2016 ◽

Vol 9 (6) ◽

pp. 136

Author(s):

Nilima R Patil

Keyword(s):

Staphylococcus Aureus ◽

Methicillin Resistant Staphylococcus Aureus ◽

Tertiary Care Hospital ◽

Tertiary Care ◽

Diffusion Method ◽

Care Hospital ◽

Disc Diffusion ◽

Disc Diffusion Method ◽

Methicillin Resistant ◽

Conventional Methods

Background:- Methicillin resistant Staphylococcus aureus (MRSA) are responsible for hospital and community acquired infections. There are many laboratory methods for detection of MRSA. Chromogenic media have been used for the last few years for the quick detection of MRSA. Objective:- Aim of this study was to compare the performance of conventional methods and chromogenic media for the detection of MRSA in a tertiary care hospital. Material and method: - 200 consecutive isolates of S. aureus confirmed by conventional methods, collected in a tertiary care hospital were used for this study. Cefoxitin and oxacillin disc diffusion test used as conventional methods and Chromogenic media i.e. oxacillin resistant screen agar base (ORSAB) was used for detection of methicillin resistant Staphylococcus aureus. All confirmed MRSA were checked by gold standard mecA base PCR method. Result: - Out of 200 isolates of Staphylococcus aureus, 50,52 and 47 strains were MRSA by Cefoxitin disc diffusion method, oxacillin disc diffusion method and oxacillin resistant screen agar base (ORSAB) method respectively. Specificity was 100%, 98.66%, 98.66% by Cefoxitin disc diffusion, oxacillin disc diffusion and ORSAB method respectively. Conclusion: - In conclusion, cefoxitin disc diffusion was the best for the phenotypic detection of MRSA because their sensitivity and specificity were better than oxacillin and ORSAB.

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Non-susceptibility trends among methicillin-resistant coagulase-negative staphylococci isolated from blood cultures

Archives of Biological Sciences ◽

10.2298/abs1401079p ◽

2014 ◽

Vol 66 (1) ◽

pp. 79-86 ◽

Cited By ~ 1

Author(s):

Anika Povazan ◽

Anka Vukelic ◽

Tatjana Kurucin ◽

Mirjana Hadnadjev ◽

Vesna Milosevic ◽

...

Keyword(s):

Diffusion Method ◽

Resistance Pattern ◽

Multiple Resistance ◽

Disc Diffusion ◽

Disc Diffusion Method ◽

Coagulase Negative Staphylococci ◽

Methicillin Resistant ◽

Resistant Strains ◽

Susceptibility Tests ◽

Hospital Acquired

Coagulase-negative staphylococci are a significant cause of hospital-acquired bacteremias. There is an increase of infections induced by methicillin-resistant strains, with growing resistance to other antibiotics. The aim of the study was to analyze the resistance of methicillin-resistant coagulase-negative staphylococci isolated from hemocultures in a five-year period. The study was carried out in the microbiology laboratory of the Institute for Pulmonary Diseases of Vojvodina, from 2008 to 2013. Coagulase-negative staphylococci were isolated from 196 hemocultures. Susceptibility tests were performed using the disc diffusion method. Of 196 coagulase-negative staphylococci, 122 (62.2%) were resistant to methicillin, of which 112 (91.8%), 105 (86.1%), 103 (84.4%), 88 (72.1%) were resistant to erythromycin, gentamicin, ciprofloxacin and clindamycin, respectively. All strains were susceptible to vancomycin and linezolid. Multiple resistance was registered in 100 (82%) strains. The most common resistance pattern was gentamicin-erythromycin-clindamycinciprofloxacin. Multiple resistance was established in a significant percentage of methicillin-resistant strains.

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Use of cefoxitin as indicator for detection of Methicillin Resistant Staphylococcus aureus

Baghdad Science Journal ◽

10.21123/bsj.8.4.947-955 ◽

2011 ◽

Vol 8 (4) ◽

pp. 947-955 ◽

Cited By ~ 1

Author(s):

Baghdad Science Journal

Keyword(s):

Staphylococcus Aureus ◽

Antimicrobial Agent ◽

Methicillin Resistant Staphylococcus Aureus ◽

Critical Diameter ◽

Brain Heart Infusion ◽

Diffusion Method ◽

Disc Diffusion ◽

Disc Diffusion Method ◽

Mannitol Salt Agar ◽

Methicillin Resistant

Rapid and accurate identification of Methicillin Resistant Staphylococcus aureus is essential in limiting the spread of this bacterium. The aim of study is the detection of Methicillin Resistant Staphylococcus aureus (MRSA) and determining their susceptibility to some antimicrobial agent. A total of fifty clinical Staphylococcus aureus, isolated from the nose of health work staff in surgery unit of Kalar general hospital and from ear of patients attended to the same hospital. The susceptibilities of isolates were determined by the disc diffusion method with oxacillin (1 ?g) and cefoxitin (30 ?g), and by the mannitol salt agar supplemented with cefoxitin (MSA-CFOX), susceptibilities of isolates to other antimicrobial agent were determined by standard disc diffusion method, Brain heart infusion (BHI) agar with vancomycin was used for detection of vancomycin resistant Staphylococcus aureus. out of fifty clinical isolates of Staphylococcus aureus 36/50(72%) considered to be MRSA according to MSA-CFOX growth and cefoxitin disc susceptibility results with critical diameter

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METHICILLIN RESISTANCE STAPHYLOCOCCUS AUREUS (MRSA) FROM CSOM IN A TERTIARY CARE HOSPITAL

10.36106/ijsr/9600960 ◽

2021 ◽

pp. 1-3

Author(s):

A.V. Kavitha ◽

Thyagarajan Ravinder ◽

Radhika Katragadda ◽

Leela Vajravelu

Keyword(s):

Staphylococcus Aureus ◽

Methicillin Resistant Staphylococcus Aureus ◽

Diffusion Method ◽

Care Hospital ◽

Disc Diffusion ◽

Disc Diffusion Method ◽

Gram Positive ◽

Suppurative Otitis Media ◽

Methicillin Resistant ◽

Sensitivity Pattern

Introduction: Chronic Suppurative Otitis Media (CSOM) is one of the major cause of preventable hearing loss if treated promptly. Emergence of resistant strains in the world is of great concern. The aim of the present study was to determine the aetiology and antibiotic sensitivity pattern of bacterial isolates from CSOM cases with special emphasis on Methicillin Resistant Staphylococcus aureus. Materials and methods: Ear swabs were collected from 212 patients attending otorhinolaryngology department, GKMC, Chennai was processed in Microbiology lab. Direct gram staining was done and then inoculated into Blood, MacConkey and Nutrient agar. Bacterial identification was done using standard microbiological techniques. Antibiotic susceptibility was done by Kirby Bauer disc diffusion technique. Methicillin Resistant Staphylococcus aureus (MRSA) was detected by Cefoxitin disc diffusion method as per CLSI guidelines. Results: 60 Gram positive bacteria were isolated from collected ear swabs. Staphylococcus aureus 46(26.59%) was the most common bacteria among Gram positive organism followed by CONS 9(5.20%) and Enterococci 5(2.89%). Staphylococcus aureus showed 41(89.13%) was sensitive to amikacin and 40(86.95%) to ofloxacin. All the Gram Positive cocci were 100% sensitive to Vancomycin and Linezolid. 19.53% were confirmed as MRSA by cefoxitin disc diffusion method. Conclusion: Microbial pattern can vary in different location in different periods of time. Hence knowledge of appropriate aetiology and antimicrobial resistance pattern of CSOM helps in rational use of antibiotics and control of drug resistance.MRSA is emerging as an important pathogen in CSOM. Empirical antibiotics should be directed to gram positives, and especially, MRSA should be taken into consideration.

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Staphylococcus aureus prevalence among preschool- and school-aged pupils

Medicina ◽

10.3390/medicina43110115 ◽

2007 ◽

Vol 43 (11) ◽

pp. 887 ◽

Cited By ~ 1

Author(s):

Žaneta Pavilonytė ◽

Justina Kačerauskienė ◽

Brigita Budrytė ◽

Tadas Keizeris ◽

Jonas Junevičius ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Methicillin Resistant Staphylococcus Aureus ◽

Diffusion Method ◽

Disc Diffusion ◽

Disc Diffusion Method ◽

Phage Group ◽

Methicillin Resistant ◽

Group Iii ◽

12Th Grade ◽

Group Ii

Object. To determine the prevalence and incidence of Staphylococcus aureus strains among preschool- and school-aged pupils and susceptibility of these strains to antimicrobial materials.Material and methods. A study of 243 preschool- and 300 school-aged pupils was conducted during 2003– 2004. Identification of Staphylococcus aureus was made with plasmacoagulase and DNase tests. The resistance of Staphylococcus aureus to antibiotics, b-lactamase activity, phagotypes, and phage groups were determined. The isolated Staphylococcus aureus strains were tested for resistance to methicillin by performing disc diffusion method using commercial discs (Oxoid) (methicillin 5 mg per disk and oxacillin 1 mg per disk). Results. A total of 292 (53.8%) Staphylococcus aureus strains were isolated and identified (113 (46.5%) from preschool- and 179 (59.7%) from school-aged pupils). The prevalence of Staphylococcus aureus strains among preschool-aged pupils varied from 46.5% to 47%. It increased to 59.0% (P>0.05) among schoolchildren aged from 11 to 15 years and to 73.0% (P<0.001) among schoolchildren aged from 16 to 19 years. Six methicillinresistant Staphylococcus aureus strains were isolated: two (1.8%) of them were from preschool-aged and four (2.2%) from school-aged pupils. The prevalence of Staphylococcus aureus strains with b-lactamase activity increased from 70.7 to 76.6% in preschool-aged pupils, and it varied from 72.0 to 79.0% in school-aged pupils (P>0.05). Staphylococcus aureus strains of phage group II (32.2–43.4%) were prevailing; nontypable Staphylococcus aureus strains made up 19.2–33.6%. Conclusions. The prevalence of Staphylococcus aureus among preschool-aged children is 41.7 to 48.8%, and it increases among 9th–12th-grade pupils (73.0%, P<0.001). Some Staphylococcus aureus strains (2.1%) were resistant to methicillin. Staphylococcus aureus strains of phage group II (39.0%, P<0.05) are most prevalent among preschool- and school-aged pupils. Pupils were colonized with methicillin-resistant Staphylococcus aureus strains belonging to phage group III phagotype 83A and 77.

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Prevalence and Antimicrobial Susceptibility Pattern of Methicillin-resistant Staphylococcus Aureus [MRSA] Isolates at a Tertiary Care Hospital in Mangalore, South India

Journal of Laboratory Physicians ◽

10.4103/0974-2727.72155 ◽

2010 ◽

Vol 2 (02) ◽

pp. 082-084 ◽

Cited By ~ 15

Author(s):

Vidya Pai ◽

Venkatakrishna I Rao ◽

Sunil P Rao

Keyword(s):

Staphylococcus Aureus ◽

Antimicrobial Susceptibility ◽

Methicillin Resistant Staphylococcus Aureus ◽

Diffusion Method ◽

Disc Diffusion ◽

Susceptibility Pattern ◽

Disc Diffusion Method ◽

Methicillin Resistant ◽

Inducible Clindamycin Resistance ◽

Antimicrobial Susceptibility Pattern

ABSTRACT Background/Aim: Methicillin-resistant Staphylococcus aureus (MRSA) is an important cause of nosocomial infections worldwide. The aim of this study was to determine the prevalence of MRSA and their antimicrobial susceptibility pattern in our hospital located in Mangalore, India. Materials and Methods: The bacterial isolates from various clinical specimens of patients admitted in our hospital were cultured as per standard protocol and all isolates of Staphylococcus aureus obtained were included in the study. The isolates were identified by standard methods like catalase test, slide and tube coagulase tests, and growth on Mannitol salt agar (HiMedia Lab, Mumbai). The antimicrobial susceptibility testing was performed by Kirby–Bauer disc diffusion method. The D-test for inducible clindamycin resistance was performed. The isolates were tested for methicillin resistance by using oxacillin disc by disc diffusion method and confirmed by agar screen test (oxacillin 6 μgm/ml). The results were interpreted according to CLSI criteria. Results: During a period of one year, a total of 237 isolates of S. aureus were studied and 69 (29.1%) were found to be methicillin-resistant. MRSA isolates showed greater resistance to multiple drugs than methicillin sensitive Staphylococcus aureus MSSA isolates. Inducible clindamycin resistance was 18.8% in MRSA as against 3.5% in MSSA. About 40–50% of MRSA were resistant to erythromycin, gentamicin, and chloramphenicol, while less than 30% were resistant to ciprofloxacin and amikacin. However, all strains were sensitive to vancomycin. Conclusion: The regular surveillance of hospital-acquired infections of MRSA may be helpful in formulating and monitoring the antibiotic policy. This may also help in preserving antibiotics like vancomycin, only for life-threatening staphylococcal diseases.

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Screening of the antimicrobial activity of marine sponge extracts from Martinique

10.1101/2021.02.16.431398 ◽

2021 ◽

Author(s):

Julie Piron ◽

Jessica Pastour ◽

Niklas Tysklind ◽

Juliette Smith-Ravin ◽

Fabienne Priam

Keyword(s):

Staphylococcus Aureus ◽

Antimicrobial Activity ◽

Inhibitory Concentration ◽

Minimum Bactericidal Concentration ◽

Marine Sponges ◽

Diffusion Method ◽

Disc Diffusion ◽

Bacterial Strains ◽

Disc Diffusion Method ◽

Staphylococcus Saprophyticus

AbstractMarine sponges are known for their antimicrobial, antifungal, and cytotoxic activity. In this study, the activity of aqueous and ethanoic extracts of 3 sponges from Martinique were tested on 5 bacterial strains: Bascillus cereus (CIP 783), Echerichia coli (CIP 54127), Pseudomonas aeruginosa (CIP A22), Staphylococcus aureus (CIP 67.8) and Staphylococcus saprophyticus (CIP 76125). The antimicrobial activity of Agelas clathrodes, Desmapsamma anchorata, and Verongula rigida, was demonstrated using the disc diffusion method and by determining the minimum inhibitory concentration and the minimum bactericidal concentration. The ethanoic extract of Agelas clathrodes had an inhibitory activity specifically on Staphylococcus aureus and Staphylococcus saprophyticus. No activity was observed for the other extracts. Further chemical analyses will be carried out in order to identify the active molecules of these sponges.

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Isolation, Characterization and Antibacterial Activity of Ergosta-5, 7, 22-triene-3β, 14α – diol (22Z) from Kenyan Ganoderma lucidum

Asian Journal of Applied Chemistry Research ◽

10.9734/ajacr/2020/v5i130127 ◽

2020 ◽

pp. 48-57

Author(s):

Ebrahim Sande ◽

Danstone Lilechi Baraza ◽

Selline Ooko ◽

Peter Kuloba Nyongesa

Keyword(s):

Staphylococcus Aureus ◽

Antibacterial Activity ◽

Streptococcus Pyogenes ◽

Ganoderma Lucidum ◽

Methicillin Resistance ◽

Hexane Extract ◽

Diffusion Method ◽

Significant Activity ◽

Disc Diffusion ◽

Disc Diffusion Method

Aims: To determine the chemical composition and antibacterial activity of Kenyan Ganoderma lucidum. Study Design: Structural determination of the isolated compound was done using spectral evidences and in comparison with literature. The antibacterial properties of the compound was done using disc diffusion method. Place and Duration of Study: Department of Pure and Applied Chemistry, Masinde Muliro University of Science and Technology, between January and November, 2019. Methodology: Sequential extraction of dried samples of Kenyan G. lucidum were done using solvents hexane, ethyl acetate and methanol. Chromatographic separation of hexane extract of Ganoderma lucidum was done using spectroscopic data. The compound was assayed against Escherichia coli, Klebsiella pneumoniae, Methicillin–Resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa and Streptococcus pyogenes. Standard antibiotic namely; ampicillin was used as the control. Disc diffusion method was used and zones of inhibition, after respective incubation periods, were used to quantify antibacterial activity. Results: From hexane extract of Ganoderma lucidum, Ergosta-5, 7, 22-triene-3β, 14α – diol (22Z) was isolated. Ethylacetate and methanol extracts produced a mixture of complex compounds. Ergosta-5,7,22-triene-3β,14α-diol (22Z) exhibited significant activity against Methicillin-Resistance Staphylococcus aureus (MRSA) (p=0.022) and Streptococcus pyogenes (p = 0.05). The most sensitive microbe was Streptococcus pyogenes. Conclusion: One major compound, Ergosta-5, 7, 22-triene-3β, 14α – diol (22Z) was isolated, characterized and antibacterial activity determined.

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