Beta-lactamase detection in Staphylococcus aureus and coagulase-negative Staphylococcus isolated from bovine mastitis

Robles, Bruno F.; Nobrega, Diego; Guimarães, F. F.; Wanderley, Guido Gomes; Langoni, Hélio

doi:10.1590/s0100-736x2014000400004

Cited by 13 publications

(11 citation statements)

References 17 publications

(20 reference statements)

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“…Although all isolates in the present investigation were phenotypically resistant to penicillin and ampicillin, the bla Z gene was detected in only one isolate (2.6%), showing discrepancy between phenotypic resistance and detection of β-lactamase gene bla Z. β-lactamase phenotype could be the result of expression of more than one gene. Moreover, there is more than one mechanism that grant staphylococci β-lactam resistance other than the expression of bla Z gene [32]. On the contrary, previous studies found higher prevalence (23.0% and 20.0%) for the bla Z gene in CoNS isolated from mastitis in cattle in Argentina [33].…”

Section: Discussionmentioning

confidence: 99%

Evolution of Antibiotic Resistance of Coagulase-Negative Staphylococci Isolated from Healthy Turkeys in Egypt: First Report of Linezolid Resistance

et al. 2019

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Coagulase-negative staphylococci (CoNS) are gaining much attention as causative agents of serious nosocomial infections in humans. This study aimed to determine the prevalence and phenotypic antimicrobial resistance of CoNS as well as the presence of resistance-associated genes in CoNS isolated from turkey farms in Egypt. Two hundred and fifty cloacal swabs were collected from apparently healthy turkeys in Egypt. Suspected isolates were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The susceptibility testing of CoNS isolates against 20 antimicrobial agents was performed using the broth microdilution test. The presence of resistance-associated genes like mecA, vanA, blaZ, erm(A), erm(B), erm(C), aac-aphD, optrA, valS, and cfr was determined. Thirty-nine CoNS were identified. All isolates were phenotypically resistant to trimethoprim/sulfamethoxazole, penicillin, ampicillin, and tetracycline. The resistance rates to erythromycin, chloramphenicol, oxacillin, daptomycin, and tigecycline were 97.4%, 94.9%, 92.3%, 89.7%, and 87.2%, respectively. Thirty-one isolates were resistant to linezolid (79.5%). Low resistance rate was detected for both imipenem and vancomycin (12.8%). The erm(C) gene was identified in all erythromycin phenotypically resistant isolates, whereas two resistant isolates possessed three resistance-conferring genes erm(A), erm(B), and erm(C). The cfr and optrA genes were detected in 11 (35.5%) and 12 (38.7%) of the 31 linezolid-resistant isolates. The mecA, aac-aphD, and blaZ genes were identified in 22.2%, 41.9%, and 2.6% of phenotypically resistant isolates to oxacillin, gentamicin, and penicillin, respectively. This is the first study revealing the correlation between linezolid resistance and presence of cfr and optrA genes in CoNS isolates from Egypt, and it can help to improve knowledge about the linezolid resistance mechanism.

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Section: Discussionmentioning

confidence: 99%

Evolution of Antibiotic Resistance of Coagulase-Negative Staphylococci Isolated from Healthy Turkeys in Egypt: First Report of Linezolid Resistance

et al. 2019

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“…The results of antimicrobial susceptibility test showed that the bacteria are resistant to all β-lactam antibiotics and oxacillin. For β-lactamase production, different phenotypic diagnostic methods that are specific and reliable such as the clover leaf and iodometric methods were used (Robles et al, 2014). The iodometric method was considered as an accurate method (Devapriya et al, 2013) while, the clover leaf method was considered as a reliable method for investigating β-lactamase production in staphylococci (Bergan et al, 1997).…”

Section: Discussionmentioning

confidence: 99%

“…Beta-lactam compounds such as penicillin continues to be one of the most frequently used drugs in veterinary medicine (Robles et al, 2014). And it is recommended as the first choice for bacteria that are inherently sensitive to it.…”

Section: Introductionmentioning

confidence: 99%

Determination of mecA expression and other resistance mechanisms in methicillin-resistant Staphylococcus aureus isolated from Oreochromis niloticus (Nile tilapia)

Magdy¹,

Rania²,

Alkhateib³

et al. 2016

Afr. J. Microbiol. Res.

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Methicillin-resistant Staphylococcus aureus is a major cause of infection worldwide. Production of β-lactamases and penicillin-binding protein 2a are the two main mechanisms of resistance in S. aureus. The aim of this work was to study the mechanisms of resistance produced by the S. aureus strain isolated from Oreochromis niloticus (Nile tilapia) during an outbreak. β-Lactamases production was detected by iodometric and clover leaf techniques. The induction of mecA gene was done using oxacillin and the gene expression was detected by real time reverse transcription-polymerase chain reaction in the induced isolate and compared with the non-induced one. Also, the studied mecA gene was sequenced to check the similarity between the gene of the tested isolate and the published mecA genes. Results showed that this isolate produces β-lactamase and mecA expression was seven times increased in the case of oxacillin induction. Sequencing results showed 99% identity between the studied gene and the published reference genes. Extensive use of antibiotics in fish farms resulted in the emergence of multidrug resistant staphylococci and this resistance may be induced by the continuous use of some antibiotics.

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“…Furthermore the emergence of other species besides Staphylococcus aureus as human pathogens, as well as, reservoirs of antimicrobial resistance and other virulence factor, increases the necessity in the developing of reliable methods for the most frequent species identification, to establish the pathogen-host relationship, as well, development of epidemiological approaches (Silva et al 2013, Silva et al 2014, Robles et al 2014). …”

Section: Introductionmentioning

confidence: 99%

Comparison phenotypic and genotypic identification of Staphylococcus species isolated from bovine mastitis

et al. 2016

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In addition to Staphylococcus aureus nowadays other coagulase-positive staphylococci (CoPS) and coagulase-negative staphylococci (CoNS), earlier considered of minor importance, are now accepted as relevant pathogens for humans and animals. The involvement of these microorganisms in bovine mastitis etiology and the possibility their transmission through milk to humans justify the requirement of developing reliable methods for identification of the most frequent species among them. The purpose of this study was to compare the phenotypic techniques with the genotypic method carried out by sequencing of the rpoB gene in identification of several species of the genus Staphylococcus isolated from bovine mastitis. A total of 300 staphylococci isolates of bovine mastitis cases from several Brazilian dairy herds were studied by phenotypic and genotypic techniques, respectively: 150 CoPS and 150 CoNS strains. A total of 18 CoNS different species and 4 CoPS species were identified. Among the CoNS the following species were recognized: 48 (32%) Staphylococcus warneri, 22(15%) S. epidermidis, 20(13%) S. hyicus, 10(7%) S. xylosus, 7(5%) S. haemolyticus, 6(4%) S. simulans, 6(4%) S. schleiferi subsp schleiferi, 6(4%) S. hominis, 5(3%) S. pasteuri, 4(2.7%) S. cohnii, 3(2%) S. saprophyticus subsp. saprophyticus 3(2%) S. chromogenes 3(2%) S. sciuri, 2(1%) S. saccharolyticus, 2(1%) S. lugdunensi, 1(0,7%) S. auricularis, 1(70%) S. saprophyticus subsp. bovis, 1(0.7%) S. capitis. And among the 150 CoPS were identified respectively: 105 (70%) S. aureus, 21(14%), S. hyicus, 19(13%) S. intermedius e 5(3%) S. schleiferi subsp coagulans. Considering the 150 CoNS isolates, the identifications performed by phenotypic and genotypic tests presented 96.7% of concordance, kappa coefficient of agreement = 0.933, SE (standard error) of kappa=0.021 (95% confidence interval: 0.893 to 0.974), Pearson's correlation coefficient (r) = 0.9977, (confidence interval 95%: 0.9938 a 0.9992) and in relation to 150 CPS isolates it was detected an agreement of 98.7%, kappa = 0.960, SE of kappa = 0.016, (95% confidence interval: 0.929 to 0.992) Pearson's correlation coefficient (r) = 0.9994 (95% confidence interval: 0.9681 to 1.0000). The verified agreement strength between the identification methods can be considered as excellent. These results assure that according to laboratory resources any of them will be suitable to perform the staphylococci identification. Considerando-se os 150 SCN isolados, as identificações realizadas por testes fenotípicos e genotípicos apresentaram 96,7% de concordância, coeficiente de concordância kappa = 0,933, SE (erro padrão) de kappa = 0,021 (95% intervalo de confiança: 0,893-0,974), coeficiente de correlação de Pearson (r) = 0,9977, (intervalo de confiança de 95%: 0,9938 a 0,9992) e em relação a 150 SCP isolados foi observado uma concordância de 98,7%, kappa = 0,960, sE de kappa = 0,016, (95% de intervalo de confiança: 0,929 a 0,992) coeficiente de correlação de Pearson (r) = 0,9994 (95% intervalo de confiança: 0,9681-1,0000). A...

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Beta-lactamase detection in Staphylococcus aureus and coagulase-negative Staphylococcus isolated from bovine mastitis

Cited by 13 publications

References 17 publications

Evolution of Antibiotic Resistance of Coagulase-Negative Staphylococci Isolated from Healthy Turkeys in Egypt: First Report of Linezolid Resistance

Evolution of Antibiotic Resistance of Coagulase-Negative Staphylococci Isolated from Healthy Turkeys in Egypt: First Report of Linezolid Resistance

Determination of mecA expression and other resistance mechanisms in methicillin-resistant Staphylococcus aureus isolated from Oreochromis niloticus (Nile tilapia)

Comparison phenotypic and genotypic identification of Staphylococcus species isolated from bovine mastitis

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