Comparison of rapid and conventional methods for investigating of mecA presence in Staphylococcus Species

Objectives: Taking the determination of mecA gene by polymerized chain reaction (PCR) method as a reference in determining methicillin resistance in Staphylococcus species, we aimed at comparing the reliability levels of disk diffusion, latex agglutination test and chromogenic agar use methods. Methods: This prospective study was conducted on 228 Staphylococcus strains isolated between January 2020 and December 2020 in Samsun Training and Research Hospital. Disk diffusion, latex agglutination and chromogen agar medium methods were applied along with the polymerized chain reaction (PCR) method. Results: The mecA gene was detected in 47 of the isolates (20.6%) by the PCR method, and these isolates were accepted as methicillin-resistant. When the PCR result was taken as a reference, the sensitivity of the disk diffusion method became 100%, and specificity became 45.9%; sensitivity of latex agglutination was determined as 80.9%, and specificity as 70.2%; sensitivity of chromogenic agar as 85.1% and its specificity was found to be 95%. Only in S. aureus isolates, the highest sensitivity and specificity rate (100% and 88%, respectively) belonged to chromogenic agar. Conclusion: Chromogenic agar provides more reliable data for S. aureus isolates, and the combined use of all three methods does not significantly increase reliability. doi: https://doi.org/10.12669/pjms.37.5.4274 How to cite this:Gorgun S, Isler H, Turgut MC. Comparison of rapid and conventional methods for investigating of mecA presence in Staphylococcus Species. Pak J Med Sci. 2021;37(5):---------. doi: https://doi.org/10.12669/pjms.37.5.4274 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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Department of Microbiology, Bangladesh Agricultural University, Mymensingh

Bangladesh Journal of Medical Microbiology ◽

10.3329/bjmm.v2i2.28839 ◽

2016 ◽

Vol 2 (2) ◽

pp. 3-6

Author(s):

Nahida Akther Zahan ◽

Md. Akram Hossain ◽

AKM Shamsuzzaman ◽

AKM Musa ◽

Md. Chand Mahamud ◽

...

Keyword(s):

Clinical Laboratory ◽

Methicillin Resistance ◽

Meca Gene ◽

Toxin Production ◽

Latex Agglutination ◽

Diffusion Method ◽

National Committee ◽

Dilution Method ◽

Agar Dilution Method ◽

Disk Diffusion Method

The study was done to detect different exotoxins among the strains of Staphylococcus aureus isolated in the department of Microbiology, Mymensingh Medical College in collaboration with the Department of Medicine under the Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh between the periods from July, 2006 to June, 2007. A total of 40 S. aureus isolates investigated in this study were identified by standard microbiological techniques. Antimicrobial susceptibility of the isolates to Oxacillin was carried out by disk diffusion method as per recommendation of the National Committee for Clinical Laboratory Standards. Any isolate showing resistance to Oxacillin was tested again by agar dilution method to determine minimum inhibitory concentration (MIC) of Methicillin. All strains were also tested for mecA gene by Polymerase Chain Reaction (PCR) for confirmation of Methicillin resistance. Enterotoxin (A-D) and Toxic Shock Syndrome Toxin-1 (TSST-1) were detected by Reverse Passive Latex Agglutination (RPLA) test. Out of 40 S. aureus isolates, 7 (17.5%) Methicillin Resistant S. aureus (MRSA), 1 (2.5%) Methicillin Sensitive S. aureus (MSSA) produced Staphylococcal Enterotoxin A (SE-A) and 1 MRSA isolate was positive for TSST-1. In case of combined toxin production among the S. aureus isolates, 2 (5%) MSSA were found to produce SE-A and SE-B, 2 (5%) MSSA produced SE-C and SE-D, and 1 (2.5%) MRSA, 1 (2.5%) MSSA produced SE-C and TSST-1.Bangladesh J Med Microbiol 2008; 02 (02): 3-6

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Detection of Methicillin Resistance in Staphylococcus Aureus by Polymerase Chain Reaction and Conventional Methods: A Comparative Study

Journal of Laboratory Physicians ◽

10.4103/0974-2727.105587 ◽

2012 ◽

Vol 4 (02) ◽

pp. 083-088 ◽

Cited By ~ 14

Author(s):

Manju M Pillai ◽

Ragunathan Latha ◽

Gautam Sarkar

Keyword(s):

Staphylococcus Aureus ◽

Polymerase Chain Reaction ◽

Methicillin Resistance ◽

Meca Gene ◽

Disk Diffusion ◽

Chain Reaction ◽

Mannitol Salt Agar ◽

Polymerase Chain ◽

Conventional Methods ◽

Phenotypic Methods

ABSTRACT Background: Methicillin-resistant Staphylococcus aureus (MRSA) is a major nosocomial pathogen worldwide, which has emerged over the past 30 years as a leading cause of both nosocomial and community-acquired infections. Accurate and rapid identification of MRSA in clinical specimens is essential for timely decision on effective antimicrobial chemotherapy. Aim: The present study was conducted to compare two conventional phenotypic methods, oxacillin disk diffusion (ODD) Aim: The present study was conducted to compare two conventional phenotypic methods, oxacillin disk diffusion (ODD) method and mannitol salt agar (MSA) with oxacillin, with polymerase chain reaction (PCR) for mecA gene (as standard). Materials and Methods: A total of 165 consecutive clinical isolates of S. aureus received at the Department of Microbiology in our tertiary care teaching hospital were included in the study. All the isolates were subjected to ODD (1 μg) method, culture in MSA with oxacillin, and PCR for mecA gene. Results: The sensitivity and specificity of ODD test were found to be 93.5% (86.4-97.3%) and 83.5% (79.2-85.8%), respectively, and that of MSA with oxacillin were found to be 87.1% (79.5-92.3%) and 89.3% (84.8-92.5%), respectively. The time taken for diagnosing MRSA by conventional methods is 48-72 h, which is more as compared to PCR which takes 18-24 h. Conclusion: This study recommends advocating PCR for mecA gene on a regular basis for detecting methicillin resistance in S. aureus isolates isolated from sterile body fluids or from special units such as intensive care units.

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Evaluation of antibiotic resistance pattern and mecA gene frequency in methicillin-resistant Staphylococcus aureus strains collected from clinical specimens in Marand hospital and treatment centers, Iran

Tabari Biomedical Student Research Journal ◽

10.18502/tbsrj.v2i4.5469 ◽

2021 ◽

Author(s):

Abolfazl Jafari-Sales ◽

Zahra Sadeghi Deylamdeh ◽

Afsoon Shariat

Keyword(s):

Staphylococcus Aureus ◽

Antibiotic Resistance ◽

Methicillin Resistant Staphylococcus Aureus ◽

Meca Gene ◽

Disk Diffusion ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Methicillin Resistant ◽

Medical Centers ◽

Wide Range

Introduction: Staphylococcus aureus causes a wide range of infections and as a multivalent pathogen is one of the causative agents of nosocomial and community infections. Therefore, the aim of this study was to identify and determine the pattern of antibiotic resistance of methicillin-resistant Staphylococcus aureus (MRSA) isolates from patients in hospitals and medical centers in Marand city and also to evaluate the presence of mecA gene. Materials and Methods: In this cross-sectional descriptive study, 385 samples of S. aureus were collected from different clinical samples of patients in hospitals and medical centers of Marand city. S. aureus was identified using standard biochemical methods. Methicillin resistance was determined by disk diffusion method in the presence of oxacillin and cefoxitin. The pattern of antibiotic resistance of the strains was determined by disk diffusion method and according to CLSI recommendation and also PCR method was used to evaluate the frequency of MecA gene. Results: In the present study, out of 385 samples of S. aureus, 215 (55.84%) samples were methicillin resistant. PCR results for mecA gene showed that 110 samples had mecA gene. The highest antibiotic resistance was observed against penicillin (100%) and erythromycin (83.63%). Most MRSA were isolated from urine and wound samples. Conclusion: The results of this study indicate the prevalence of methicillin-resistant species and also the increase in antibiotic resistance of MRSA to various antibiotics. Therefore, in order to prevent increased resistance to other antibiotics, it is recommended to avoid inappropriate use of antibiotics.

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Evaluation of the CLSI cefoxitin 30-µg disk-diffusion method for detecting methicillin resistance in staphylococci

Clinical Microbiology and Infection ◽

10.1111/j.1469-0691.2006.01522.x ◽

2006 ◽

Vol 12 (10) ◽

pp. 1039-1042 ◽

Cited By ~ 8

Author(s):

L.-X. Zhu ◽

Z.-W. Zhang ◽

C. Wang ◽

H.-W. Yang ◽

Q. Zhang ◽

...

Keyword(s):

Methicillin Resistance ◽

Disk Diffusion ◽

Diffusion Method ◽

Disk Diffusion Method

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Ceftazidime – Avibactam susceptibility among carbapenem-resistant Enterobacterales in a pilot study in Turkey

Acta Microbiologica et Immunologica Hungarica ◽

10.1556/030.2021.01525 ◽

2021 ◽

Author(s):

Hasan Selcuk Ozger ◽

Ebru Evren ◽

Serap Suzuk Yildiz ◽

Cigdem Erol ◽

Fatma Bayrakdar ◽

...

Keyword(s):

Practical Method ◽

Disk Diffusion ◽

Diffusion Method ◽

Drug Resistant ◽

Chain Reaction ◽

Disk Diffusion Method ◽

Carbapenem Resistant ◽

Therapeutic Choice ◽

Polymerase Chain

AbstractThis study aimed to detect carbapenemase genes and to determine the in vitro susceptibility of Ceftazidime-Avibactam (CZA) in Enterobacterales isolates. Carbapenemase genes were detected by polymerase chain reaction. CZA sensitivity of isolates was evaluated with broth microdilution (BMD) and disk diffusion methods. A total of 318 carbapenem-resistant Enterobacterales isolates were included. Most of the isolates (n = 290, 91.2%) were identified as Klebsiella pneumoniae. The most common carbapenemase type was OXA-48 (n = 82, 27.6%). CZA susceptibility was evaluated in 84 isolates with OXA-48 and KPC carbapenemase activity. Both BMD and disk diffusion methods revealed that 95.2% of the isolates were sensitive to CZA; whereas, 4 (4.76%) isolates were resistant to CZA. Among colistin resistant isolates, 96.5% (n = 80) of them were susceptible to CZA. Our study demonstrated high in vitro efficacy of CZA in Enterobacterales isolates producing OXA-48 carbapenemase. High susceptibility rates against colistin resistant isolates which generally are also pan drug resistant, makes CZA a promising therapeutic choice for difficult-to-treat infections. Due to its high correlation with the BMD, disk diffusion method is a suitable and more practical method in detecting CZA in vitro activity.

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P1601 Evaluation the cefoxitin 30 m G disk diffusion method for detection of methicillin-resistance in selected Staphylococcus aureus isolates

International Journal of Antimicrobial Agents ◽

10.1016/s0924-8579(07)71440-1 ◽

2007 ◽

Vol 29 ◽

pp. S450

Author(s):

M. Lara ◽

N. Batista ◽

F. Laich ◽

S. Méndez-Álvarez

Keyword(s):

Staphylococcus Aureus ◽

Methicillin Resistance ◽

Disk Diffusion ◽

Diffusion Method ◽

Disk Diffusion Method

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Characteristics of coagulase positive staphylococci isolated from milk in cases of subclinical mastitis

Acta veterinaria ◽

10.2478/acve-2014-0012 ◽

2014 ◽

Vol 64 (1) ◽

pp. 115-123 ◽

Cited By ~ 4

Author(s):

Nataša Rajić Savić ◽

Vera Katić ◽

Branko Velebit

Keyword(s):

Meca Gene ◽

Subclinical Mastitis ◽

Penicillin G ◽

Diffusion Method ◽

Disc Diffusion ◽

Disk Diffusion Method ◽

Phenotypic Resistance ◽

High Virulence ◽

Pcr Method ◽

Coagulase Positive Staphylococci

Abstract Coagulase-positive staphylococci are the most common pathogen causing subclinical mastitis in cows. Their main characteristic is a high virulence which leads to chronic infection. A total of 213 isolates of coagulase-positive staphylococci were tested. The majority of isolates (58%) formed a gold pigment, then light gold (28%), white gold (8%), golden gray, creamy white and white (2%). The majority of isolated coagulase-positive staphylococci produce beta hemolysis on esculin blood agar (50%), alpha and beta hemolysis (36%), beta and delta hemolysis (8%), delta hemolysis (4%), and alpha hemolysis (2%). Biochemical and molecular identification was performed by APISTAPH and multiplex PCR method. The majority of isolates were identified as S. aureus (88%), S. chromogenes (4%), and 2% of the isolates were identified as S. lentus, S. sciuri, S. xylosus, S. intermedius by APISTAPH. Antimicrobial susceptibility to penicillin G, was found by the Kirby Bauer disk diffusion method to be resistant (62.44%). For disc diffusion penicillin G sensitive isolates the minimal inhibitory concentration (MIC) was established for MIC50 and MIC90 as 0.003 mg/ml and 2μg/ml, respectively. For disc diffusion penicillin G resistant isolates MIC50 and MIC90 was 1.0μg/ml and 16μg/ ml, respectively. The study of phenotypic resistance to methicillin, as recommended by CLSI, established resistance to oxacillin in 5.26% of the isolates, while no resistance was found to cefoxitine. None of the tested isolates have the mecA gene.

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A study of inducible clindamycin resistance in erythromycin resistant clinical isolates of Staphylococcus species

Asian Journal of Medical Sciences ◽

10.3126/ajms.v6i6.11811 ◽

2015 ◽

Vol 6 (6) ◽

pp. 48-52

Author(s):

Fatima Khan ◽

Sana Ali ◽

Asfia Sultan ◽

Meher Rizvi ◽

Abida Khatoon ◽

...

Keyword(s):

Methicillin Resistance ◽

Clinical Isolates ◽

Disk Diffusion ◽

Diffusion Method ◽

Clinical Failure ◽

Coagulase Negative Staphylococci ◽

Sensitivity Testing ◽

Disk Diffusion Method ◽

Methicillin Resistant ◽

Inducible Clindamycin Resistance

Introduction: Erythromycin resistant Staphylococcus isolates with inducible resistance appear sensitive to clindamycin in in?vitro sensitivity testing. If clindamycin is used for treatment of such isolates, selection for constitutive mutants may lead to clinical failure. Current study was conducted to detect the presence of inducible clindamycin resistance in erythromycin resistant Staphylococcus isolates by disk diffusion method (D test). To correlate clindamycin resistance phenotypes with minimum inhibitory concentrations (MICs) of clindamycin, erythromycin, oxacillin and vancomycin among the isolates. To correlate various resistance phenotypes with methicillin resistance. Material and Methods: 150 non duplicate isolates of Staphylococcus species were identified and antibiotic susceptibility testing was done using Kirby Bauer’s disc diffusion method. MICs were determined using E?test for oxacillin, vancomycin, clindamycin and erythromycin using E?test strips (Himedia) Results: Among 150 staphylococcus clinical isolates, 96 were of S. aureus and 54 were coagulase negative Staphylococci (CONS). About 81.2% of the S.aureus isolates and 72.2% of the CONS were found to be methicillin resistant. Inducible clindamycin resistance was found in 39.3% of the isolates, constitutive resistance phenotype in 48% while 12.7% demonstrated MS phenotype. 18% and 11.3% of all the isolates had MICs for clindamycin between 0.01?0.06 μg/ml and 0.06?0.1 respectively. 12.5% had MIC ranging from 4?8 μg/ml while 58% had MIC > 8 μg/ml. Constitutive resistant phenotype (cMLS) was the predominant phenotype in methicillin resistant isolates. MS phenotype was the predominant among MSSA (methicillin sensitive S. aureus) while MSCNS (methicillin sensitive CONS) cMLS (46.7%) predominated. MIC of all erythromycin resistant isolates were ≥ 240 μg/ml. Nearly 16.7% of the cMLS and 57.9% of MS isolates were found to be oxacillin sensitive and 83% of iMLS and 83.3% of MS phenotype isolates were oxacillin resistant on MIC testing. 47.2% of cMLS and 73.6% of MS isolates had MIC ≤ 2 μg/ml for vancomycin and 52.7% of cMLS and 26.3% of MS isolates had MICs in intermediate range for vancomycin. Conclusions: D?testing might help clinicians to decide whether to use clindamycin in Staphylococcal infections when erythromycin resistance is present. Determination of MICs help to identify exact sensitivity profile of isolates in cases where clinical failure occurs due to misleading disk diffusion tests.DOI: http://dx.doi.org/10.3126/ajms.v6i6.11811 Asian Journal of Medical Sciences Vol.6(6) 2015 48-52

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The Phenotypic and Genetic Detection of the Methicillin-Resistant Staphylococcus aureus (MRSA)

Journal of Emerging Diseases and Virology ◽

10.16966/2473-1846.157 ◽

2020 ◽

Vol 5 (3) ◽

Author(s):

Eftychios V ◽

Laura VM ◽

Calina-Oana Z ◽

Evangelos V ◽

Marina P ◽

...

Keyword(s):

Meca Gene ◽

Latex Agglutination ◽

Agglutination Test ◽

Latex Agglutination Test ◽

Disk Diffusion ◽

Methicillin Resistant ◽

Pcr Method ◽

Resistant Strains ◽

Mrsa Strains ◽

Cefoxitin Disk

Methicillin resistant strains of Staphylococcus aureus (MRSA) were identified shortly upon the introduction of methicillin into the clinical practice. The S. aureus samples were taken from patients hospitalized in General Hospital of Chania “Agios Georgios”. The strains were isolated from different pathological products, in the hospital laboratory. All isolates were tested using the cefoxitin disk diffusion, the oxacillin MIC methods and the PBP2’ latex agglutination test (bioMérieux), for the production of the Penicillin-Binding Protein 2a (PBP2a or PBP2’ protein). S. aureus ATCC 29213 was used as a negative control. We followed the detection of the mecA gene throughout the PCR method, as the standard “gold” method, in order to identify MRSA strains. Conventional methods for MRSA strains detection were compared with the PCR method. The antibiotic susceptibility testing was performed throughout the Kirby-Bauer disk diffusion method using antibiotic discs from Bioanalyse ltd. The mecA gene was found by PCR in 57.5 % of S. aureus strains, which allowed defining the isolated strains as MRSA strains. According to the oxacillin MIC values of the studied strains, 25 strains (53.2%) were identified as MRSA, 21 (44.68%) as MSSA and 1*strain (2.13%) as Borderline (BL) MRSA. The mecA gene is present in 24 of the MRSA strains with oxacillin MIC ≥ 4 being more common in strains showing the oxacillin MICs ≥ 256 (12/27). Adding the BL strains to the methicillin resistant strains, the rate of the MRSA strains increases to 26 (55.32%), the appropriate values of the MRSA strains percent, as determined by the PCR method (57.45%), which shows a concordance of 96.3% (26/27), between the results obtained by the two tests. Comparing the results obtained using the PCR method; with the oxacillin MICs and the PBP2’ latex agglutination test, concordant results were obtained for 89.36% of the strains (42/47) by oxacillin MICs and for 97.87% of the strains (46/47) by PBP2’ latex agglutination test. We conclude that the specificity of these methods is 100% for the mecA PCR method, 97.87% for the PBP2a latex method and 89.36% for the oxacillin MIC. The comparison of phenotypic methods (the PBP2a latex reaction, oxacillin MICs, the Cefoxitin disk diffusion test with the genotypic methods (the presence of the mecA gene), reveals that the PBP2a latex reaction has high sensitivity (97.87%), and can be used as an alternative method to PCR for the MRSA detection, in resource constraint settings.

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EVALUATION OF THE METHOSD FOR DETECTION METHICILLIN-RESISTANT STAPHYLOCOCCUS AUREUS.

Journal of Medicine and Pharmacy ◽

10.34071/jmp.2013.5.4 ◽

2013 ◽

pp. 25-31

Author(s):

Thi Kim Chi Nguyen ◽

Dinh Binh Tran ◽

Thi Nam Lien Nguyen ◽

Van Tuan Mai ◽

Godreuil Sylvain

Keyword(s):

Staphylococcus Aureus ◽

Methicillin Resistant Staphylococcus Aureus ◽

Methicillin Resistance ◽

Meca Gene ◽

Antibiotic Sensitivity ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Antibiotic Resistant ◽

Methicillin Resistant ◽

Resistant Strains

Objective: To evaluate the infections that caused by Methicillin-resistant Staphylococcus aureus and the value of the tests to detect Methicillin-resistant Staphylococcus aureus. Subjects and Methods: Used routine techniques to culture and isolate S.aureus, test the antibiotic sensitivity by Kirby-Bauerr, determination the Methicillin-resistant Staphylococcus aureus by Oxacillin and cefoxitin disc and PCR in identified the mecA gene Staphylococcus aureus. Results: The rate of Staphylococcus aureus isolated is highest which isolated from pus specimens (55.06%). In 267 strains of Staphylococcus aureus isolated in the Department of Microbiology, Hue Central Hospital the Methicillin resistance Staphylococcus aureus was 61.42%. The level of antibiotic resistant strains of Methicillin-resistant Staphylococcus aureus is higher than that in Methicillin-sensitive strains. Conclusion: Cefoxitin 30 microg disk diffusion method to detect Methicillin resistance is effective for determinate Methicillin-resistant Staphylococcus aureus (sensitivity and specificity are all 100.00%). Key words: Staphylococcus aureus Methicillin-resistant.

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