Molecular detection and typing of methicillin-resistant Staphylococcus aureus and methicillin-resistant coagulase-negative staphylococci isolated from cattle, animal handlers, and their environment from Karnataka, Southern Province of India

Background and Aim: Methicillin-resistant staphylococci are among the emerging pathogens which have become a threat to both human and animal health. The present investigation intended to examine the occurrence and the molecular characteristics of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant coagulase-negative staphylococci (MRCoNS) recovered from cattle, its handlers, and their environment. Materials and Methods: A total of 666 specimens were subjected to culture method and genus-specific polymerase chain reaction (PCR) for the identification of Staphylococcus. Methicillin resistance was substantiated by PCR identification of mecA and mecC resistance determinants. Species-specific identification of mecA positive isolates was conducted by multiplex PCR. The unidentified species were deciphered by 16S rRNA gene sequencing approach. The mecA positive isolates were further characterized by staphylococcal cassette chromosome mec (SCCmec) typing and multilocus sequence typing (MLST). Results: Duplex PCR identified 728 Staphylococcus isolates, of which 66 (9%) were positive for mecA gene. MRSA constituted 24% of the total mecA positive isolates. Among MRCoNS, Staphylococcus epidermidis (42%), and Staphylococcus haemolyticus (11%) were the most common species identified. Overall, 47% of the mecA positive isolates belonged to SCCmec type V. MLST analysis showed eight different sequence types (STs) among MRSA isolates of which five were novel STs. Among methicillin-resistant S. epidermidis, 19 different STs were found, of which nine novel STs were detected. Conclusion: The increase in the prevalence of mecA positive staphylococci, especially MRCoNS in cattle is a great concern in view of their transmission potential. Hence, continuous monitoring and molecular characterization of methicillin-resistant staphylococci should be elucidated in human and animal sectors so as to prevent the spread of these resistant pathogens.

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Mannitol Fermenting Methicillin-Resistant Coagulase Negative Staphylococci Isolated From Diabetic Foot Infections

International Journal of Research in Pharmaceutical Sciences ◽

10.26452/ijrps.v11i4.3281 ◽

2020 ◽

Vol 11 (4) ◽

pp. 6095-6101

Author(s):

Samira Fattah Hamid ◽

Aza Bahadeen Taha

Keyword(s):

Staphylococcus Aureus ◽

Diabetic Foot ◽

Methicillin Resistance ◽

Meca Gene ◽

Rrna Gene ◽

Human Pathogens ◽

Coagulase Negative Staphylococci ◽

Mannitol Salt Agar ◽

Methicillin Resistant ◽

Diabetic Foot Infections

Detection of mannitol fermenting coagulase-negative staphylococci is frequently unnoticed when Staphylococcus aureus is screening in the laboratory. On the other hand, the emergence of coagulase-negative staphylococci as critical human pathogens need dependable methods for the identification of clinically significant coagulase-negative staphylococci to understand the epidemiology of infections caused by these bacteria. The study aimed to identify mannitol fermenting coagulase-negative staphylococci that assumed to be Staphylococcus aureus as they formed yellow colonies on Mannitol Salt agar plates. Samples were taken from eighty-four patients with diabetic foot infections. The specimen was cultured on Blood agar and Mannitol Salt agar. Mannitol fermenting coagulase-negative staphylococci isolates diagnosed through Vitek2 system then confirmed by detecting 16S rRNA gene and absence of the nuc gene. Antibiotic sensitivity and methicillin resistance were detected by Vitek2 system, then methicillin resistance was confirmed by Oxacillin Salt Agar Screen test and detection of the mecA gene. Out of 81 Staphylococcus isolated from foot and nose of diabetic foot patients, twenty isolates were mannitol fermenting coagulase-negative staphylococci, they related to following species; Staphylococcus haemolyticus, staphylococcus lentus, Staphylococcus xylosus, Staphylococcus lugdunensis, Staphylococcus hominis, Staphylococcus galinarum and Staphylococcus saprophyticus). The majority of them (85%) were phenotypically methicillin-resistant and genotypically harbouring mecA gene. 80% were resistant to Erythromycin, 70% to Clindamycin, 35% to Trimethoprim-Sulphamethoxazole, 30% to Gentamicin and Rifampicin, 15% to Levofloxacin and Teicoplanin. 30% expressed inducible clindamycin resistance.

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Multiplex Polymerase Chain Reaction Based Typing of Staphylococcal Chromosomal Cassette mec of Methicillin Resistant Staphylococcus aureus from Selected Hospitals in Lahore

IIUM Medical Journal Malaysia ◽

10.31436/imjm.v9i1.734 ◽

2020 ◽

Vol 9 (1) ◽

Author(s):

Romeeza T ◽

Naeem R ◽

Nadeem A

Keyword(s):

Staphylococcus Aureus ◽

Methicillin Resistant Staphylococcus Aureus ◽

Methicillin Resistance ◽

Sccmec Type ◽

Meca Gene ◽

Methicillin Resistant ◽

Different Types ◽

Type Ia ◽

Polymerase Chain ◽

Sccmec Types

Introduction: Staphylococcus aureus is one of the leading causes of nosocomial infections. Prevalence of methicillin resistant Staphylococcus aureus (MRSA) has been reported in up to 42% of isolates in Pakistan. Methicillin resistance is encoded by the mecA gene and it is transferred by a unique genetic vector called staphylococcal chromosomal cassette (SCCmec). Depending upon the selection pressures of antibiotics, different types of SCCmec elements may prevail in different parts of the world. Materials and Methods: Therefore, this study was designed to fi nd out the major SCCmec types present in selected hospitals of Lahore. For this purpose thirty fi ve MRSA isolates were collected. These strains were reconfi rmed and SCCmec types were determined by multiplex PCR. Results: It was found that 21 (60%) isolates possess SCCmec type IA while 14 (40%) isolates possess SCCmec type IIC. Conclusion: These cassettes are shown to be multiresistant and have not been reported in other Asian countries so far.

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Occurrence and characteristics of methicillin resistant Staphylococcus aureus and methicillin resistant coagulase-negative staphylococci in raw milk manufacturing

Czech Journal of Food Sciences ◽

10.17221/4443-cjfs ◽

2012 ◽

Vol 29 (Special Issue) ◽

pp. S11-S16 ◽

Cited By ~ 11

Author(s):

M. Vyletělová ◽

H. Vlková ◽

I. Manga

Keyword(s):

Staphylococcus Aureus ◽

Methicillin Resistant Staphylococcus Aureus ◽

Methicillin Resistance ◽

Meca Gene ◽

Diffusion Method ◽

Biochemical Tests ◽

Coagulase Negative Staphylococci ◽

Disk Diffusion Method ◽

Methicillin Resistant ◽

Staphylococcal Cassette Chromosome

For monitoring the occurrence of MRSA (methicillin resistant Staphylococcus aureus) and MR-CNS (methicillin resistant coagulase-negative staphylococci), cow’s, goat’s, and sheep’s milks (bulk milks and individual samples) were investigated. Human nasal and throat swabs of the farm staff and nasal swabs of animals were also investigated as well. In total 1729 samples were examined and 634 strains were isolated by means of the cultivation method and used in this study. Generic identification of the staphylococci isolates was done performed by biochemical tests and all S. aureus and CNS isolates were checked by the PCR method for the presence of mecA gene which is responsible for methicillin resistance. The presence of the staphylococcal cassette chromosome mec (SCCmec), Panton-Valentine leukocidin (pvl) and genes encoding toxic shock syndrome toxin (tst) was detected in all strains confirmed as MRSA. The species were also examined for antimicrobial susceptibility by using disk diffusion method with antibiotic disks. S. aureus was the most frequently identified species from the samples tested (n = 557; 32.2%), followed by S. haemolyticus (n = 32; 1.9%), S. chromogenes (n = 24; 1.4%), S. epidermidis (n = 20; 1.2%), and S. caprae (n = 1; 0.16%). Among the resistant staphylococci (n = 49), S. aureus (n = 25; 51%) was found the most frequently, followed by S. epidermidis (n = 17; 34.7%), S. chromogenes (n = 6; 12.2%), and S. haemolyticus (n = 1; 2%). The resistant Staphyloccocus sp. occurred mainly in cow’s milk (MRSA, S. epidermidis, S. chromogenes, S. haemolyticus) and in animal’s swabs (S. epidermidis). One MRSA was also found in goat’s milk and one was isolated from human swab. No resistant strains were found in sheep’s milk. The negative results of the analysed genes presence (pvl, tst) were identical with all MRSA tested. The staphylococcal cassette chromosome mec (SCCmec) was classified as type IV or V.

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The First Report of a Methicillin-Resistant Staphylococcus aureus Isolate Harboring Type IV SCCmec in Thailand

Pathogens ◽

10.3390/pathogens10040430 ◽

2021 ◽

Vol 10 (4) ◽

pp. 430

Author(s):

Wichai Santimaleeworagun ◽

Praewdow Preechachuawong ◽

Wandee Samret ◽

Tossawan Jitwasinkul

Keyword(s):

Staphylococcus Aureus ◽

Resistance Genes ◽

Methicillin Resistant Staphylococcus Aureus ◽

Methicillin Resistance ◽

Sccmec Type ◽

Clinical Strain ◽

Spa Typing ◽

Methicillin Resistant ◽

Type Iv ◽

Antimicrobial Resistance Genes

Methicillin-resistant Staphylococcus aureus (MRSA) is mostly found in Thailand in the hospital as a nosocomial pathogen. This study aimed to report the genetic characterization of a clinical community-acquired MRSA (CA-MRSA) isolate collected from hospitalized patients in Thailand. Among 26 MRSA isolates, S. aureus no. S17 preliminarily displayed the presence of a staphylococcal cassette chromosome mec (SCCmec) type IV pattern. The bacterial genomic DNA was subjected to whole-genome sequencing. Panton–Valentine leukocidin (PVL) production, virulence toxins, and antibiotic resistance genes were identified, and multi-locus sequence typing (MLST) and spa typing were performed. The strain was matched by sequence to MLST type 2885 and spa type t13880. This strain carried type IV SCCmec with no PVL production. Five acquired antimicrobial resistance genes, namely blaZ, mecA, Inu(A), tet(K), and dfrG conferring resistance to β-lactams, lincosamides, tetracycline, and trimethoprim, were identified. The detected toxins were exfoliative toxin A, gamma-hemolysin, leukocidin D, and leukocidin E. Moreover, there were differences in seven regions in CR-MRSA no. S17 compared to CA-MRSA type 300. In summary, we have reported the ST2885-SCCmec IV CA-MRSA clinical strain in Thailand for the first time, highlighting the problem of methicillin resistance in community settings and the consideration in choosing appropriate antibiotic therapy.

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Detection of mecA gene by latex agglutination and its molecular analysis by PCR in methicillin resistant staphylococcus aureus.

The Professional Medical Journal ◽

10.29309/tpmj/2020.27.07.3752 ◽

2020 ◽

Vol 27 (07) ◽

pp. 1363-1370

Author(s):

Aneela Khawaja ◽

Iffat Javed ◽

Sohaila Mushtaq ◽

Saeed Anwar ◽

Faiqa Arshad ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Methicillin Resistant Staphylococcus Aureus ◽

Methicillin Resistance ◽

Meca Gene ◽

Latex Agglutination ◽

Medical Institute ◽

Cross Sectional ◽

Methicillin Resistant ◽

Agglutination Method ◽

Resistant Strains

Antimicrobial resistance (AMR) is a devastating question that is threatening the health globally. The extensive and indiscriminative use of antibiotics has evolved a notorious resistance in Staphylococcus aureus. This resistance developed through possession of mecA gene, which codes for modified penicillin binding protein (PBP2a) and the emergent strain being labeled “methicillin resistant Staphylococcus aureus”. Conventional phenotypic techniques for detection of MRSA rely on standardization of cultural characteristics. The drawbacks of diagnostic error to report MRSA include: poor prognosis, expensive treatment, dissemination of multi-drug resistant strains and even treatment failure. Latex agglutination method can be adopted as a more accurate and quick strategy for rapid detection of methicillin resistance. Objectives: To compare detection of mecA gene in methicillin resistant isolates of Staphylococcus aureus by latex agglutination and PCR; by assessing the sensitivity and specificity of both methods. Study Design: Descriptive Cross-Sectional study. Setting: Pathology Department, Post Graduate Medical Institute, Lahore. Period: From January 2015 to December 2015; according to standard operating procedures at Microbiology laboratory. Material & Methods: A total 713 consecutive, non-duplicate isolates of Staphylococcus aureus were processed. Methicillin resistance was determined using cefoxitin (30mg) by Kirby-Bauer method using CLSI guideline (2016), latex agglutination method; and PCR for mecA gene. Results: The results showed that out of 713 Staphylococcus aureus isolates, 92 (12.90%) isolates were resistant to cefoxitin and were labelled as MRSA. majority MRSA isolates recovered from pus (44.57%) and wound swab (20.65%), followed by blood (13.04%), fluid (8.70%), CSF (4.35%), CVP (3.26%), HVS (3.26%) and tracheal secretion (2.17%). By latex agglutination method, 87 (94.50%) were positive for PBP2a; while on PCR mecA gene was detected only in 82 (89.10%) MRSA isolates. When assessed with PCR (gold standard) the sensitivity and diagnostic accuracy of latex agglutination was 100% and 94.57%, respectively. Conclusion: Latex agglutination test can be employed as rapid and reliable diagnostic technique in MRSA isolates for mecA gene detection, where resources for molecular methods are inadequate. This can effectually lessen the misdiagnosis of resistant strains, and over/ ill-use of antibiotics.

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Occurrence of Methicillin-Resistant Coagulase-Negative Staphylococci (MRCoNS) and Methicillin-Resistant Staphylococcus aureus (MRSA) from Pigs and Farm Environment in Northwestern Italy

Antibiotics ◽

10.3390/antibiotics10060676 ◽

2021 ◽

Vol 10 (6) ◽

pp. 676

Author(s):

Miryam Bonvegna ◽

Elena Grego ◽

Bruno Sona ◽

Maria Cristina Stella ◽

Patrizia Nebbia ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Human Health ◽

Environmental Samples ◽

Methicillin Resistant Staphylococcus Aureus ◽

Bacterial Species ◽

Meca Gene ◽

Nucleotide Sequencing ◽

Coagulase Negative Staphylococci ◽

Methicillin Resistant ◽

Nasal Swabs

Swine farming as a source of methicillin-resistant Staphylococcus aureus (MRSA) has been well documented. Methicillin-resistant coagulase-negative staphylococci (MRCoNS) have been less studied, but their importance as pathogens is increasing. MRCoNS are indeed considered relevant nosocomial pathogens; identifying putative sources of MRCoNS is thus gaining importance to prevent human health hazards. In the present study, we investigated MRSA and MRCoNS in animals and environment in five pigsties in a high farm-density area of northwestern Italy. Farms were three intensive, one intensive with antibiotic-free finishing, and one organic. We tested nasal swabs from 195 animals and 26 environmental samples from three production phases: post-weaning, finishing and female breeders. Phenotypic tests, including MALDI-TOF MS, were used for the identification of Staphylococcus species; PCR and nucleotide sequencing confirmed resistance and bacterial species. MRCoNS were recovered in 64.5% of nasal swabs, in all farms and animal categories, while MRSA was detected only in one post-weaning sample in one farm. The lowest prevalence of MRCoNS was detected in pigs from the organic farm and in the finishing of the antibiotic-free farm. MRCoNS were mainly Staphylococcus sciuri, but we also recovered S. pasteuri, S. haemolyticus, S. cohnii, S. equorum and S. xylosus. Fifteen environmental samples were positive for MRCoNS, which were mainly S. sciuri; no MRSA was found in the farms’ environment. The analyses of the mecA gene and the PBP2-a protein highlighted the same mecA fragment in strains of S. aureus, S. sciuri and S. haemolyticus. Our results show the emergence of MRCoNS carrying the mecA gene in swine farms. Moreover, they suggest that this gene might be horizontally transferred from MRCoNS to bacterial species more relevant for human health, such as S. aureus.

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Characteristics of Erythromycin Resistance in Methicillin-Resistant Staphylococcus aureus Isolated From Raw Milk

International Journal of Enteric Pathogens ◽

10.15171/ijep.2019.25 ◽

2019 ◽

Vol 7 (4) ◽

pp. 121-125

Author(s):

Fatemeh Mahdavi ◽

Fatemeh Zaboli ◽

Rahem Khoshbakht

Keyword(s):

Staphylococcus Aureus ◽

Resistance Genes ◽

Methicillin Resistant Staphylococcus Aureus ◽

Methicillin Resistance ◽

Meca Gene ◽

Raw Milk ◽

Erythromycin Resistance ◽

Methicillin Resistant ◽

Inducible Clindamycin Resistance ◽

Mrsa Strains

Background: Methicillin-resistant Staphylococcus aureus (MRSA) strains are one of the most important multidrug resistant microorganisms that threaten human health. Objective: The present study was conducted to evaluate genotypic and phenotypic characteristics of erythromycin resistance among MRSA isolates recovered from raw milk in Iran. Materials and Methods: A total of 50 MRSA isolates were recovered from raw milk. Tests for erythromycin and clindamycin susceptibility and inducible clindamycin resistance were done. In addition, the presence of the methicillin resistance determinant (mecA), erythromycin resistance genes (ermA, ermB, ermC and msrA) and an important virulence gene (Panton– Valentine leukocidin) were investigated using polymerase chain reaction (PCR) method. Results: Forty-eight percent (24/50) and 46% (23/50) of the isolates were resistant to erythromycin and clindamycin, respectively. Seven (14%) isolates showed inducible clindamycin resistance phenotype. The mecA gene was detected in 88% (44/50) of MRSA isolates. The incidence of the ermA, ermB, ermC and msrA genes was 14%, 64%, 12%, and 26%, respectively and the PVL gene was present in 18% (9/50) of MRSA isolates. Conclusion: According to the results of the study, the incidence of erythromycin resistance genes and inducible clindamycin-resistant MRSA strains was high in raw milk samples in Iran.

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Dressed chicken as potential vehicle for spread of methicillin-resistant Staphylococcus aureus in Sokoto, Nigeria

Future Science OA ◽

10.2144/fsoa-2020-0066 ◽

2020 ◽

Vol 6 (10) ◽

pp. FSO619

Author(s):

Ibrahim A Musawa ◽

Yusuf Yakubu ◽

Bashiru Garba ◽

Fatimah M Ballah ◽

Hassan Abdurrahman Jibril ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Methicillin Resistant Staphylococcus Aureus ◽

Methicillin Resistance ◽

Meca Gene ◽

Resistance Screening ◽

Methicillin Resistant ◽

Oxacillin Resistance ◽

Chicken Carcass ◽

Biochemical Analyses

Aim: To evaluate the role of dressed chicken in the spread of methicillin-resistant Staphylococcus aureus (MRSA) in Sokoto, Nigeria. Materials and methods: 190 chicken carcass rinsates were subjected to culture and biochemical analyses to isolate and identify MRSA. PCR was used to amplify mecA gene that is responsible for methicillin resistance. Results & conclusion: Culture and molecular analysis showed 19.5% (37/190) of the rinse had MRSA on oxacillin-resistance screening agar base (ORSAB) with 7.9% (15/190) possessing the mecA gene. Significant association (p = 0.044) exist between local-chicken and presence of MRSA, being twice more likely to have MRSA compared to exotic-chickens (odds ratio [OR] = 2.132). Results indicate possible role of dressed-chicken in the spread of MRSA. Authorities should regulate the sale and use of antibiotics by farmers, and enhance hygienic practices at slaughterhouses.

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Rapid Discrimination of Methicillin-Resistant Staphylococcus aureus by MALDI-TOF MS

Pathogens ◽

10.3390/pathogens8040214 ◽

2019 ◽

Vol 8 (4) ◽

pp. 214 ◽

Cited By ~ 8

Author(s):

Kim ◽

Chung ◽

Han ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Decision Tree ◽

Methicillin Resistant Staphylococcus Aureus ◽

Methicillin Resistance ◽

Sccmec Type ◽

Simple Discrimination ◽

Methicillin Resistant ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Tof Ms

Methicillin-resistant Staphylococcus aureus (MRSA) is a serious pathogen in clinical settings and early detection is critical. Here, we investigated the MRSA discrimination potential of matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) using 320 clinical S. aureus isolates obtained in 2005–2014 and 181 isolates obtained in 2018. We conducted polymerase chain reactions (PCR) for staphylococcal cassette chromosome mec (SCCmec) typing and MALDI-TOF MS to find specific markers for methicillin resistance. We identified 21 peaks with significant differences between MRSA and methicillin-susceptible S. aureus (MSSA), as determined by mecA and SCCmec types. Each specific peak was sufficient to discriminate MRSA. We developed two methods for simple discrimination according to these peaks. First, a decision tree for MRSA based on six MRSA-specific peaks, three MSSA-specific peaks, and two SCCmec type IV peaks showed a sensitivity of 96.5%. Second, simple discrimination based on four MRSA-specific peaks and one MSSA peak had a maximum sensitivity of 88.3%. The decision tree applied to 181 S. aureus isolates from 2018 had a sensitivity of 87.6%. In conclusion, we used specific peaks to develop sensitive MRSA identification methods. This rapid and easy MALDI-TOF MS approach can improve patient management.

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Prevalence and molecular epidemiology of methicillin-resistant Staphylococcus aureus colonization with and without methicillin-resistant coagulase-negative Staphylococci in HIV-infected patients

10.21203/rs.3.rs-17504/v1 ◽

2020 ◽

Author(s):

Ying Li ◽

Jialing Lin ◽

Linghua Li ◽

Weiping Cai ◽

Yingying Wang ◽

...

Keyword(s):

Risk Factors ◽

Staphylococcus Aureus ◽

Tract Infection ◽

Methicillin Resistant Staphylococcus Aureus ◽

Mainland China ◽

Molecular Characteristics ◽

Coagulase Negative Staphylococci ◽

Methicillin Resistant ◽

History Of ◽

Mrsa Colonization

Abstract Background The global prevalence of methicillin-resistant Staphylococcus aureus (MRSA) colonization in human immunodeficiency virus (HIV)-infected patients is increasing, but data about it was limited in mainland China. This study aims to investigate the epidemiology of MRSA nasal colonization among HIV-infected patients in mainland China and also evaluate the impact of methicillin-resistant coagulase-negative Staphylococci (MRCoNS). Methods This cross-sectional study was designed to collect nasal samples and individual information for HIV-infected participants. Risk factors and phenotypic and molecular characteristics among those with MRSA colonization comparing those with and without MRCoNS co-colonization were analyzed.Results We found 119 (11.89%) out of 1001 HIV-infected patients were colonized with MRSA, including 41 (4.10%) with MRCoNS and 78 (7.79%) without MRCoNS. Having a history of respiratory tract infection in the previous 6 months(adjusted OR=1.64, 95% CI: 1.04-2.57) and male gender (aOR=3.92, 95% CI: 1.20-12.85) were risk factors for the overall MRSA and MRSA without MRCoNS colonization, respectively. No risk factor was associated with co-colonization of MRSA and MRCoNS. The proportions of antibiotic resistance and toxin genes as well as the distribution of molecular types for MRSA isolates were equivalent between subjects with and without MRCoNS isolates (P-value ≥0.05). Conclusions HIV-infected patients remain a highly vulnerable population for MRSA colonization, and men and prior history of respiratory tract infection are risk factors. Risk factors and phenotypic and molecular characteristics of MRSA colonization were not affected by co-colonizing with MRCoNS.

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