scholarly journals New update on molecular diversity of clinical Staphylococcus aureus isolates in Iran: Antimicrobial resistance, adhesion and virulence factors, biofilm formation and SCCmec typing

2021 ◽  
Author(s):  
Mahtab Tabandeh ◽  
Hami Kaboosi ◽  
Mojtaba Taghizadeh Armaki ◽  
Abazar Pournajaf ◽  
Fatemeh Peyravii Ghadikolaii
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Resistance ◽  
Virulence Factors ◽  
Resistance Genes ◽  
Biofilm Formation ◽  
Clonal Selection ◽  
Clinical Samples ◽  
Inducible Resistance ◽  
Antibiotic Susceptibility Test ◽  
Wide Range

Abstract Staphylococcus. aureus is often considered as a potential pathogen and resistant to a wide range of antibiotics. The pathogenicity of this bacterium is due to the presence of multiple virulence factors and ability to form biofilm. SCCmec types I, II and III are mainly attributed to HA-MRSA, while SCCmec types IV and V have usually been reported in CA-MRSA infections. In this study, we performed a cross-sectional study in order to determine the antimicrobial resistance, adhesion and virulence factors, biofilm formation and SCCmec typing of clinical S. aureus isolates in Iran. S. aureus isolate was identified using microbiological standard methods and antibiotic susceptibility test was performed as described by the Clinical and Laboratory Standards Institute (CLSI) guidelines. Inducible resistance phenotype and biofilm formation were determined using D-test and tissue culture plate methods, respectively. Multiplex-PCRs were performed to detect adhesion and virulence factors, antibiotic resistance genes, biofilm formation and SCCmec typing by specific primers. Among 143 clinical samples, 67.8% were identified as MRSA. All isolates were susceptible to vancomycin. The prevalence of cMLSB, iMLSB and MS phenotypes were 61.1%, 22.2% and 14.8%, respectively. The TCP method revealed that 71.3% of isolates were able to form biofilm. The predominant virulence and inducible resistance genes in both MRSA and MSSA isolates were related to sea and ermC respectively. SCCmec type III was the predominant type. Data show the high prevalence rates of virulence elements among S. aureus isolates, especially MRSA strains. This result might be attributed to antibiotic pressure, facilitating clonal selection.

Antimicrobial Resistance Profile and Quinolone Resistance Genes in Staphylococcus aureus from Patients Attending Federal Medical Centre Keffi, Nigeria

2020 ◽  
pp. 1-15
Author(s):  
E. A. Sunday ◽  
Y. B. Ngwai ◽  
R. H. Abimiku ◽  
I. H. Nkene ◽  
Y. Ibrahim ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Resistance ◽  
Resistance Genes ◽  
Multidrug Resistant ◽  
Quinolone Resistance ◽  
Medical Centre ◽  
Clinical Samples ◽  
Resistance Profile ◽  
Antimicrobial Resistance Profile ◽  
Pcr Method

Aims: This study investigated the antimicrobial resistance profile and quinolone resistance genes in Staphylococcus aureus from patients attending Federal Medical Centre, Keffi, Nigeria. Methodology: A total of 240 clinical samples which comprised of high vaginal swabs, endocervical swabs, sputum, ear swabs, wound swabs, semen and eye swabs, were collected from the patients. Staphylococcus aureus was isolated and identified from these samples using standard microbiological method. Antimicrobial susceptibility testing of the isolates was performed and interpreted in accordance with the Clinical and Laboratory Standards Institute (CLSI) method. Ciprofloxacin-resistant S. aureus were screened for quinolone resistance genes using Polymerase Chain Reaction (PCR) method. Results: Out of 240 clinical samples, the prevalence of S. aureus was 21.3%. The prevalence in relation to clinical samples was higher in eye swab (45.5%) and ear swab (44.4%), but lower in sputum (14.5%). The isolates were more resistant to oxacillin (88.2%), sulphamethoxazole/ trimethoprim (82.4%) and erythromycin (76.5%), but less resistant to ciprofloxacin (19.6%) and levofloxacin (5.9%). The most common resistance phenotypes in the isolates were sulfamethoxazole/trimethoprim (SXT) - clindamycin (DA) – ofloxacin (OX) - erythromycin (E) - rifampicin (RD) and SXT-DA-OX-E- streptomycin (S) -RD with an occurrence of (13.7%) each. The percentage occurrences of multidrug resistant and extensive-drug resistant isolates were 92.2% and 7.8% respectively. The occurrences of quinolone resistance genes in the ciprofloxacin-resistant isolates were: aac(6′)-Ib-cr (60.0%), gyrA and gyrB (50.0%), parC (40.0%), qnrB (20.0%) and qnrS (10.0%). Conclusion: The isolates were less resistant to levofloxacin, cefoxitin, ciprofloxacin and gentamicin in the study location. Most of the ciprofloxacin-resistant isolates harbored quinolone resistance genes with aac(6′)-Ib-cr as the most common.

scholarly journals Isolation and molecular characterization of staphylococcus aureus isolated from clinical cases in broilers

2020 ◽  
Vol 11 (2) ◽  
pp. 42-62
Author(s):  
Anas Almousawi ◽  
Abdullah Alhatami ◽  
Keyword(s):  
Staphylococcus Aureus ◽  
Antibiotic Resistance ◽  
Resistance Genes ◽  
Antibiotic Susceptibility ◽  
Biofilm Formation ◽  
Susceptibility Test ◽  
Poultry Industry ◽  
Antibiotic Susceptibility Test ◽  
Class 1 ◽  
Clinical Cases

Background: Staphylococcus aureus (S. aureus) causes a difficult problem in the poultry industry because it causes diseases that are difficult to treat due to the resistance of these bacteria to antibiotics and their possession of a battery of virulence and resistance genes in addition to their ability to produce thick biofilms. Method: A cross-sectional study conducted to collect a total of 53 samples from different clinical cases in broilers during the period from August 2019 to February 2020 in Al-Najaf and Karbala cities, The clinical isolates were determined by using the conventional standard biochemical tests. All the specimens cultured on blood agar medium supplemented with 5% blood for primary isolation and selected by using selective media mannitol salt agar (MSA) for confirmation the mannitol fermentation, then subjected to gram’s staining, catalase, oxidase, and further slide coagulase test, then all S. aureus isolates tested by antibiotic susceptibility test, and screened for the presence of mecA and mecC genes using PCR for the detection of MRSA isolates, then subjected to the detection of virulence genes (pvl and eta), antibiotic resistance gene (cfr), identification of integron class 1, biofilm formation assay, the multi-druge resistance profiles (MDR) and multible antibiotics resistance (MAR) indexes were calculated. Results: the isolation rate of S. aureus from the broilers' clinical samples was 37.7%. The antibiotic susceptibility test revealed that 85% of S. aureus isolates were resistant to one or more of the antibiotic tested. All 53 isolates were assessed for the presence of mecA and mecC genes by using PCR. The mecA gene-specific PCR product was seen in 7 (35%) isolates and considered as MRSA. Among all S. aureus isolates, two isolates were positive for the eta gene, and 15 (75%) isolates harboring integron class 1, while the biofilm formation test revealed that 7 (35%) was positive biofilm producers and three of them were strong producers, consequentlly, 13 (65%) of the isolates were resisted to three or more antibiotics and considered as MDR strains. While pvl, cfr, and mecC gene were not detected among S. aureus isolates. Conclusion: the current study revealed that S. aureus possess a real threat in the poultry industry reflecting a public health problem due to the large acquisition of antibiotic resistance genes by these bacteria, the results indicated a high percentage of isolates having MDR characteristic, and two of them were resistant to all antibiotics tested. In addition to the presence of two MRSA isolates carrying the eta gene, this indicating that they are of human origin.

scholarly journals Recent Developments in Phenotypic and Molecular Diagnostic Methods for Antimicrobial Resistance Detection in Staphylococcus aureus: A Narrative Review

Diagnostics ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 208
Author(s):  
Andrea Sanchini
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Resistance ◽  
Food Poisoning ◽  
Opportunistic Pathogen ◽  
Narrative Review ◽  
Diagnostic Methods ◽  
Molecular Diagnostic ◽  
Clinical Samples ◽  
Wide Range ◽  
Resistance Detection

Staphylococcus aureus is an opportunistic pathogen responsible for a wide range of infections in humans, such as skin and soft tissue infections, pneumonia, food poisoning or sepsis. Historically, S. aureus was able to rapidly adapt to anti-staphylococcal antibiotics and become resistant to several classes of antibiotics. Today, methicillin-resistant S. aureus (MRSA) is a multidrug-resistant pathogen and is one of the most common bacteria responsible for hospital-acquired infections and outbreaks, in community settings as well. The rapid and accurate diagnosis of antimicrobial resistance in S. aureus is crucial to the early initiation of directed antibiotic therapy and to improve clinical outcomes for patients. In this narrative review, I provide an overview of recent phenotypic and molecular diagnostic methods for antimicrobial resistance detection in S. aureus, with a particular focus on MRSA detection. I consider methods for resistance detection in both clinical samples and isolated S. aureus cultures, along with a brief discussion of the advantages and the challenges of implementing such methods in routine diagnostics.

scholarly journals Methicillin-Resistant Staphylococcus aureus Clonal Complex 398 as a Major MRSA Lineage in Dogs and Cats in Thailand

Antibiotics ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 243
Author(s):  
Surawit Chueahiran ◽  
Jitrapa Yindee ◽  
Pongthai Boonkham ◽  
Nipattra Suanpairintr ◽  
Pattrarat Chanchaithong
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Resistance ◽  
Resistance Genes ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Clonal Complex ◽  
Clinical Samples ◽  
Methicillin Resistant ◽  
Class A ◽  
Antimicrobial Resistance Genes ◽  
Mrsa St398

The aim of this study was to present molecular and antimicrobial resistance characteristics of methicillin-resistant Staphylococcus aureus (MRSA) clonal complex (CC) 398 isolated from diseased dogs and cats in Thailand. A total of 20 MRSA isolates of 134 Staphylococcus aureus isolated from canine and feline clinical samples during 2017–2020 were CC398, consisting of sequence type (ST) 398 (18 isolates), ST5926 (1 isolate), and ST6563 (1 isolate) by multilocus sequence typing. spa t034 and staphylococcal cassette chromosome mec (SCCmec) V were predominantly associated with ST398. Intraclonal differentiation was present by additional spa (t1255, t4653), non-detectable spa, composite SCCmec with a hybrid of ccrA1B1+ccrC and class A mec complex, and DNA fingerprints by pulsed-field gel electrophoresis. The isolates essentially carried antimicrobial resistance genes, mediating multiple resistance to β-lactams (mecA, blaZ), tetracyclines [tet(M)], aminoglycosides [aac(6′)-Ie-aph(2′)-Ia], and trimethoprim (dfr). Livestock-associated MRSA ST398 resistance genes including lnu(B), lsa(E), spw, fexA, and tet(L) were heterogeneously found and lost in subpopulation, with the absence or presence of additional erm(A), erm(B), and ileS2 genes that corresponded to resistance phenotypes. As only a single CC398 was detected with the presence of intraclonal variation, CC398 seems to be the successful MRSA clone colonizing in small animals as a pet-associated MRSA in Thailand.

scholarly journals Biofilm Formation and Methicillin Resistance of Staphylococcus aureus Isolated from Clinical Samples

10.3823/841 ◽  
2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Abdelraouf A. Elmanama ◽  
Islam Majdi Al-Aydi ◽  
Mariam R. Al-Reefi
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Resistance ◽  
Biofilm Formation ◽  
Antimicrobial Agents ◽  
Methicillin Resistance ◽  
Gaza Strip ◽  
Diffusion Method ◽  
Clinical Samples ◽  
Disk Diffusion Method ◽  
High Tendency

Background: Staphylococcus aureus including methicillin resistant S. aureus (MRSA) is one of the most effective biofilm-forming organisms, biofilm contribute in protecting the microorganism from host defenses and prevent the effective penetration of antimicrobial agents. Biofilm formation is considered as an important contributing factor for the initiation and establishment of chronic infection by S. aureus and known as a major obstacle in the treatment of S. aureus infections is their ability to develop resistance to antimicrobials. Aims : To screen clinical Staphylococcus aureus including MRSA isolates for their biofilm forming abilities and their association with antimicrobial resistance. Methods: A total of 196 clinical isolates of S. aureus were obtained from different sample sources using standard microbiological techniques from three major hospitals in Gaza strip. Biofilm formation of these isolates was determined by tissue culture plate (TCP) method and tube adherence method (TM). Antimicrobial susceptibility test was performed using the modified Kirby–Bauer disk diffusion method as per Clinical and Laboratory Standards Institute guidelines. MRSA was detected using the cefoxitin disk test. Results: Biofilm formation was observed in 174 (88.8 %) and in 145 (74.0%) isolates of S. aureus via TCP method and TM, respectively. The highest resistance percent was for penicillin (92.9%), followed by cefoxitin (80.6%) and oxacillin (67.9%), while the lowest resistance percent was for linezolid and ceftaroline (1%). Among the 196 isolates 71.4% (N=140) were classified as MDR with a MAR index (≥ 0.2). A total of 158 isolates (80.6%) were identified as MRSA distributed as 90.4%, 79.4% and 70.9% from Al-Shifa, Al-Nasser pediatrics and Al-Aqsa hospitals respectively. Large proportions (82.1%) of biofilm producers were identified as MRSA. Biofilm-producing MRSA exhibited a higher percent (90.5%) when compared with the biofilm non-producer MRSA (9.5%). Importantly, 89.2% of biofilm-producing S. aureus were multidrug resistant. Conclusions: S. aureus isolates possessed high biofilm-forming ability. Biofilm-producing strains have very high tendency to exhibit antimicrobial resistance, multidrug resistance and methicillin resistance. Regular surveillance of biofilm formation by S. aureus and their antimicrobial resistance profile may lead more success in treating S. aureus infections.   Keywords: Biofilm, MDR, MRSA, TCP, TM, Gaza strip, Palestine.

scholarly journals Distribution and Clonal Diversity of Staphylococcus aureus and Other Staphylococci in Surface Waters: Detection of ST425-t742 and ST130-t843 mecC-Positive MRSA Strains

Antibiotics ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 1416
Author(s):  
Vanessa Silva ◽  
Eugénia Ferreira ◽  
Vera Manageiro ◽  
Lígia Reis ◽  
María Teresa Tejedor-Junco ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Multidrug Resistance ◽  
Antimicrobial Resistance ◽  
Virulence Factors ◽  
Resistance Genes ◽  
Surface Waters ◽  
Water Samples ◽  
Coagulase Negative Staphylococci ◽  
Spa Typing ◽  
Antimicrobial Resistance Genes

Natural aquatic environments represent one of the most important vehicles of bacterial dissemination. Therefore, we aimed to isolate staphylococci from surface waters and to investigate the presence of antimicrobial resistance genes and virulence factors as well as the genetic lineages of all Staphylococcus aureus isolates. Staphylococci were recovered from water samples collected from 78 surface waters, including rivers, streams, irrigation ditches, dams, lakes, and fountains. The presence of antimicrobial resistance genes and virulence factors was investigated by PCR. Multilocus sequence typing and spa-typing were performed in all S. aureus isolates. From the 78 water samples, 33 S. aureus, one S. pseudintermedius, and 51 coagulase-negative staphylococci (CoNS) were identified. Among the S. aureus isolates, four MRSA were identified, and all harbored the mecC gene. Fourteen S. aureus were susceptible to all antimicrobials tested and the remaining showed resistance to penicillin, erythromycin and/or tetracycline encoded by the blaZ, ermT, msr(A/B), tetL, and vgaA genes. Regarding the clonal lineages, one mecC-MRSA isolate belonged to spa-type t843 and sequence type (ST) 130 and the other three to t742 and ST425. The remaining S. aureus were ascribed 14 spa-types and 17 sequence types. Eleven species of CoNS were isolated: S. sciuri, S. lentus, S. xylosus, S. epidermidis, S. cohnii spp. urealyticus, S. vitulinus, S. caprae, S. carnosus spp. Carnosus, S. equorum, S. simulans, and S. succinus. Thirteen CoNS isolates had a multidrug resistance profile and carried the following genes: mecA, msr(A/B), mph(C), aph(3′)-IIIa, aac(6′)-Ie–aph(2′’)-Ia, dfrA, fusB, catpC221, and tetK. A high diversity of staphylococci was isolated from surface waters including mecCMRSA strains and isolates presenting multidrug-resistance profiles. Studies on the prevalence of antibiotic-resistant staphylococci in surface waters are still very scarce but extremely important to estimate the contribution of the aquatic environment in the spread of these bacteria.

scholarly journals Culture-Independent Genotyping, Virulence and Antimicrobial Resistance Gene Identification of Staphylococcus aureus from Orthopaedic Implant-Associated Infections

2021 ◽  
Vol 9 (4) ◽  
pp. 707
Author(s):  
J. Christopher Noone ◽  
Fabienne Antunes Ferreira ◽  
Hege Vangstein Aamot
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Resistance ◽  
Resistance Genes ◽  
Virulence Gene ◽  
Orthopaedic Implant ◽  
Metagenomic Sequencing ◽  
Gene Detection ◽  
Shotgun Metagenomic Sequencing ◽  
Antimicrobial Resistance Genes ◽  
Culture Independent

Our culture-independent nanopore shotgun metagenomic sequencing protocol on biopsies has the potential for same-day diagnostics of orthopaedic implant-associated infections (OIAI). As OIAI are frequently caused by Staphylococcus aureus, we included S. aureus genotyping and virulence gene detection to exploit the protocol to its fullest. The aim was to evaluate S. aureus genotyping, virulence and antimicrobial resistance genes detection using the shotgun metagenomic sequencing protocol. This proof of concept study included six patients with S. aureus-associated OIAI at Akershus University Hospital, Norway. Five tissue biopsies from each patient were divided in two: (1) conventional microbiological diagnostics and genotyping, and whole genome sequencing (WGS) of S. aureus isolates; (2) shotgun metagenomic sequencing of DNA from the biopsies. Consensus sequences were analysed using spaTyper, MLST, VirulenceFinder, and ResFinder from the Center for Genomic Epidemiology (CGE). MLST was also compared using krocus. All spa-types, one CGE and four krocus MLST results matched Sanger sequencing results. Virulence gene detection matched between WGS and shotgun metagenomic sequencing. ResFinder results corresponded to resistance phenotype. S. aureus spa-typing, and identification of virulence and antimicrobial resistance genes are possible using our shotgun metagenomics protocol. MLST requires further optimization. The protocol has potential application to other species and infection types.

scholarly journals Whole genome-based characterisation of antimicrobial resistance and genetic diversity in Campylobacter jejuni and Campylobacter coli from ruminants

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Medelin Ocejo ◽  
Beatriz Oporto ◽  
José Luis Lavín ◽  
Ana Hurtado
Keyword(s):  
Genetic Diversity ◽  
Antimicrobial Resistance ◽  
Campylobacter Jejuni ◽  
Resistance Genes ◽  
Campylobacter Coli ◽  
Whole Genome ◽  
Northern Spain ◽  
Sequence Alignments ◽  
Phenotypic Data ◽  
Wide Range

AbstractCampylobacter, a leading cause of gastroenteritis in humans, asymptomatically colonises the intestinal tract of a wide range of animals.Although antimicrobial treatment is restricted to severe cases, the increase of antimicrobial resistance (AMR) is a concern. Considering the significant contribution of ruminants as reservoirs of resistant Campylobacter, Illumina whole-genome sequencing was used to characterise the mechanisms of AMR in Campylobacter jejuni and Campylobacter coli recovered from beef cattle, dairy cattle, and sheep in northern Spain. Genome analysis showed extensive genetic diversity that clearly separated both species. Resistance genotypes were identified by screening assembled sequences with BLASTn and ABRicate, and additional sequence alignments were performed to search for frameshift mutations and gene modifications. A high correlation was observed between phenotypic resistance to a given antimicrobial and the presence of the corresponding known resistance genes. Detailed sequence analysis allowed us to detect the recently described mosaic tet(O/M/O) gene in one C. coli, describe possible new alleles of blaOXA-61-like genes, and decipher the genetic context of aminoglycoside resistance genes, as well as the plasmid/chromosomal location of the different AMR genes and their implication for resistance spread. Updated resistance gene databases and detailed analysis of the matched open reading frames are needed to avoid errors when using WGS-based analysis pipelines for AMR detection in the absence of phenotypic data.

scholarly journals Virulence Factors in Coagulase-Negative Staphylococci

Pathogens ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 170
Author(s):  
Angela França ◽  
Vânia Gaio ◽  
Nathalie Lopes ◽  
Luís D. R. Melo
Keyword(s):  
Antibiotic Resistance ◽  
Virulence Factors ◽  
Resistance Genes ◽  
Biofilm Formation ◽  
Antibiotic Resistance Genes ◽  
Coagulase Negative Staphylococci ◽  
Healthcare Associated ◽  
Major Pathogens

Coagulase-negative staphylococci (CoNS) have emerged as major pathogens in healthcare-associated facilities, being S. epidermidis, S. haemolyticus and, more recently, S. lugdunensis, the most clinically relevant species. Despite being less virulent than the well-studied pathogen S. aureus, the number of CoNS strains sequenced is constantly increasing and, with that, the number of virulence factors identified in those strains. In this regard, biofilm formation is considered the most important. Besides virulence factors, the presence of several antibiotic-resistance genes identified in CoNS is worrisome and makes treatment very challenging. In this review, we analyzed the different aspects involved in CoNS virulence and their impact on health and food.

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