Sensitivity to Antibiotics of Staphylococcus Aureus Strains, Able to Biofilm Formation

The problem of respiratory diseases associated with staphylococcal carriers is considered to be one of the most acute in modern society due to its high prevalence and problems with treatment due to the high resistance of these bacteria to antibiotics. The purpose of the study was to determine the sensitivity of Staphylococcus aureus strains, able to form biofilm, isolated from the upper respiratory tract of human. Materials and methods. Bacteriological methods of isolation and identification of staphylococci, the method of rapid determination of the ability to form biofilm on a tablet and the disk-diffusion method of determining the susceptibility to antibiotics were used to perform the research. As a result of the conducted researches it was established that in the structure of pathogens of exacerbations of seasonal rhinitis S. aureus prevailed. It was isolated from 34 samples of biological material from the nose, which accounted for 69.4% of all examined cases of rhinitis. Staphylococcus spp. (6.1%) and Streptococcus spp. (24.5%) among the isolated strains of S. aureus, 27 (79.4%) had the ability to form a biofilm. A feature associated with antibiotic resistance is the ability of strains of microorganisms to form a biofilm, in which they acquire enhanced ability to survive under adverse environmental factors, including the use of drugs. Results and discussion. In our research we showed that more than 80% of film-forming strains were found to be susceptible to ciprofloxacin, amoxicillin / clavulanic acid and azithromycin. 4 (14.8%) are methicillin-resistant. Resistance to methicillin was detected simultaneously with resistance to ciprofloxacin (3 cases) and to azithromycin (2 cases), 1 strain was resistant to gentamicin and 2 – to tetracycline. 1 of the methicillin-resistant strains of S. aureus was multidrug-resistant (showed resistance to all studied antibiotics). Among non-biofilm strains, more than 80% of the strains were also sensitive to ciprofloxacin, amoxicillin / clavulanic acid and azithromycin. Sensitivity to tetracycline was low in both groups (42-63% sensitive). Conclusion. The prevalence of antibiotic resistance among clinical strains of opportunistic bacteria, unfortunately, shows an increasing trend. This requires constant monitoring of susceptibility to antimicrobial drugs in order to develop schemes of rational antibiotic therapy, taking into account the individualized approach to patients. In this sense, it is promising when studying the biological properties of clinical isolates to determine not only the resistance to antibiotics, but also their ability to form a biofilm

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Antibiotic resistance pattern of Staphylococcus aureus with reference to MRSA isolates from pediatric patients

10.21203/rs.2.10785/v1 ◽

2019 ◽

Author(s):

Raja Ram Gurung ◽

Prashanna Maharjan ◽

Ganga GC

Keyword(s):

Staphylococcus Aureus ◽

Antibiotic Resistance ◽

Pediatric Patients ◽

Methicillin Resistant Staphylococcus Aureus ◽

Current Status ◽

Clinical Samples ◽

Resistance Pattern ◽

Isolation And Identification ◽

Cross Sectional ◽

Methicillin Resistant

Abstract Background: Staphylococcus aureus is one of the important superbugs distributed throughout the world. It causes minor skin infections to severe complications including nosocomial infections in both hospitals and community settings. These strains have multi-drug resistant property. Hence, they are difficult to manage which increase health-related costs and simultaneously intensifying the need for new antibiotics. The extent of Methicillin-Resistant Staphylococcus aureus (MRSA) in children is largely unknown. The study determines the current status of S. aureus and MRSA causing various infections in pediatric patients visiting International Friendship Children’s Hospital (IFCH). Methods: A cross-sectional study was conducted among patients visiting a hospital. Various clinical specimens were aseptically collected and processed according to standard microbiological procedures. Isolation and identification of S. aureus were done by microscopy, mannitol fermentation, and coagulase positivity. All identified S. aureus isolates subjected to in-vitro antibiogram by Kirby-Bauer disc diffusion technique adopting Clinical and Laboratory Standards Institute (CLSI) guideline. Isolates resistant to cefoxitin were considered to be MRSA. Whereas, isolates produced D-shaped inhibition zone around clindamycin when kept near erythromycin were considered to be Inducible Clindamycin Resistant (ICR). Results: 672 various types of clinical samples were processed from the microbiology laboratory from June and November 2015. Out of 300 culture positive samples, 52 (17.3%) were S. aureus isolates, among them 39 (75.0%) were found to be MRSA. The D-test showed that Macrolide-Lincosamide-Streptogramin-B (MLSB) phenotype was 15.4%. Conclusion: The study shows the MRSA occurrence is prevalent in pediatric patients and newer classes’ drugs are found more effective than β-lactam drugs to treat S. aureus infection. However, restriction on the indiscriminate use of such drugs may be an effective strategy to control the drug resistance. Keywords: Methicillin-Resistant Staphylococcus aureus (MRSA), Macrolide-Lincosamide-Streptogramin B (MLSB) phenotype, Inducible Clindamycin Resistant (ICR) test or D-zone test, Antibiotic resistance, Nepal

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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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Novel Antibiotic Combinations of Diverse Subclasses for Effective Suppression of Extensively Drug-Resistant Methicillin-Resistant Staphylococcus aureus (MRSA)

International Journal of Microbiology ◽

10.1155/2020/8831322 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Shumyila Nasir ◽

Muhammad Sufyan Vohra ◽

Danish Gul ◽

Umm E Swaiba ◽

Maira Aleem ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Clavulanic Acid ◽

Antimicrobial Agents ◽

Methicillin Resistant Staphylococcus Aureus ◽

Multidrug Resistant ◽

Methicillin Resistant ◽

Development Of Resistance ◽

Amoxicillin Clavulanic Acid ◽

Combination Antibiotics ◽

Time Kill

The emergence of multidrug-resistant pathogens such as methicillin-resistant Staphylococcus aureus (MRSA), the chief etiological agent for a range of refractory infections, has rendered all β-lactams ineffective against it. The treatment process is further complicated with the development of resistance to glycopeptides, primary antibiotics for treatment of MRSA. Antibiotic combination therapy with existing antimicrobial agents may provide an immediate treatment option. Minimum inhibitory concentrations (MICs) of 18 different commercially available antibiotics were determined along with their 90 possible pairwise combinations and 64 triple combinations to filter out 5 best combinations. Time-Kill kinetics of these combinations were then analyzed to find collateral bactericidal combinations which were then tested on other randomly selected MRSA isolates. Among the top 5 combinations including levofloxacin-ceftazidime; amoxicillin/clavulanic acid-tobramycin; amoxicillin/clavulanic acid-cephradine; amoxicillin/clavulanic acid-ofloxacin; and piperacillin/tazobactam-tobramycin, three combinations were found to be collaterally effective. Levofloxacin-ceftazidime acted synergistically in 80% of the tested clinical MRSA isolates. First-line β-lactams of lower generations can be used effectively against MRSA infection when used in combination. Antibiotics other than glycopeptides may still work in combination.

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Carriage Methicillin-Resistant Staphylococcus aureus in Poultry and Cattle in Northern Algeria

Veterinary Medicine International ◽

10.1155/2018/4636121 ◽

2018 ◽

Vol 2018 ◽

pp. 1-5 ◽

Cited By ~ 3

Author(s):

Saliha Bounar-Kechih ◽

Mossadak Taha Hamdi ◽

Hebib Aggad ◽

Nacima Meguenni ◽

Zafer Cantekin

Keyword(s):

Staphylococcus Aureus ◽

Antibiotic Resistance ◽

Broiler Chickens ◽

Methicillin Resistant Staphylococcus Aureus ◽

Laying Hens ◽

Methicillin Resistance ◽

Public Health Problem ◽

Cross Resistance ◽

Isolation And Identification ◽

Methicillin Resistant

Multiresistant and especially Methicillin-Resistant Staphylococcus aureus (MRSA) poses a serious public health problem that requires their immediate identification and antibiotic resistance characteristics. In order to determine antibiotic resistance S. aureus poultry and bovine origin, 8840 samples were collected from slaughterhouses in the northern region of Algeria between years 2009 and 2014. 8375 samples were from an avian origin (1875 from laying hens and 6500 from broiler chickens) and the rest was from bovine origin. Bacteriological isolation and identification were made by classical culture method and antibiotic resistance patterns were determined by disc diffusion test. The prevalence of S. aureus was 42% in laying hens, 12% in broilers, and 55% in bovine samples. The prevalence of MRSA was 57%, 50%, and 31% in laying hens, broiler chickens, and bovine, respectively. While MRSA strains isolated from poultry showed cross-resistance to aminoglycosides, fluoroquinolones, macrolides, sulphonamides, and cyclins, those isolated from bovine also revealed similar multiresistance except for sulphonamide. This high percentage of methicillin resistance and multidrug resistance in S. aureus poultry and bovine origin may have importance for human health and curing of human infections.

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STUDY OF ANTIBIOTIC-RESISTANCE AND SENSITIVITY PATTERN IN A TERTIARY CARE TEACHING HOSPITAL

International Journal of Advanced Research ◽

10.21474/ijar01/13888 ◽

2021 ◽

Vol 9 (12) ◽

pp. 161-168

Author(s):

Sailajapriyadarsini Parlapalli ◽

◽

V.V Padmavathy ◽

Gunapati Rama Mohan Reddy ◽

◽

...

Keyword(s):

Staphylococcus Aureus ◽

Antibiotic Resistance ◽

Clavulanic Acid ◽

Body Fluid ◽

Tertiary Care ◽

Antibiotic Use ◽

Study Data ◽

Urine Samples ◽

Sensitivity Pattern ◽

Amoxicillin Clavulanic Acid

Introduction: Antibiotics are helpful in bacterial infection control and management. Irrational antibiotic use leads to resistance, which puts modern medicines achievements at risk. This study aims to know antibiotic resistance and sensitivity patterns and to assess possible factors that favor the development of antibiotic resistance. Methods: It is a retrospective observational study. Data collected from June 2019 to May 2020 from the culture & sensitivity records of various clinical isolates at the Microbiology department of SMC, Vijayawada, and analyzed by descriptive statistics. Results: Total samples collected 2905. Only746 samples showed significant growth. Most commonly, isolated organisms were from Pus and Body fluids Staphylococcus aureus (31.16%), Klebsiella (23.02%), from blood samples Staphylococcus aureus (44%,) Klebsiella (32%), from urine samples Escherichia coli (27.31%),Staphylococcus aureus (16.66%). Bacteria isolated from, Blood and Pus & body fluid samples showed more resistance to Amoxicillin + Clavulanic acid, 60% &58.60%, and urine samples showed more resistance to Norfloxacin69.44%. Conclusion: In this study, bacteria isolated from, blood, pus, and body fluid samples showed more resistance to Amoxicillin + Clavulanic acid, from urine samples showed more resistance to Norfloxacin. Parenterally used drugs like aminoglycosides and vancomycin have retained their sensitivity but bacteria also showed resistance to Imipenem, Vancomycin, new combinations like Cefoperazone + Sulbactam. A culture & sensitivity test and following antibiotic stewardship guidelines before prescribing antibiotics will give good results to prevent antibiotic resistance.

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A study on Methicillin resistant Staphylococcus aureus mastitis in dairy cows

Journal of Applied and Natural Science ◽

10.31018/jans.v6i2.427 ◽

2014 ◽

Vol 6 (2) ◽

pp. 356-361 ◽

Cited By ~ 1

Author(s):

D. Chandrasekaran ◽

P. Venkatesan ◽

K. G. Tirumurugaan ◽

A. P. Nambi ◽

P. S. Thirunavukkarasu ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Dairy Cows ◽

Methicillin Resistant Staphylococcus Aureus ◽

Clinical Mastitis ◽

Penicillin G ◽

Diffusion Method ◽

Isolation And Identification ◽

Methicillin Resistant ◽

Milk Samples ◽

Agar Disc

Methicillin-resistant Staphylococcus aureus (MRSA) poses a serious problem in dairy animals suffering from mastitis. The study was carried out to evaluate the incidence of Methicillin resistant S. aureus from clinical mastitis milk samples and their antibiotic resistance profile and characterised with respect to the molecular features that contributed to the resistance in these pathogens. Isolation and identification of Methicillin resistant S. aureus were performed from acute clinical mastitis samples. The isolates were tested using agar disc diffusion method for their antimicrobial susceptibility and modified resazurin assay micro dilution technique for MIC to 8 different antimicrobial drugs. A total of 235 clinical mastitis milk samples from dairy cows were cultured for incidence of S. aureus. Methicillin resistant S. aureus was isolated from a total of 12 (44.25%) of the 116 S. aureus samples. Based on the antimicrobial sensitivity and MIC results, MRSA isolates were found sensitive to gentamicin, enrofloxcain, amoxicillin+sulbactam, ceftriaxone and resistant to amoxicillin, oxytetracycline, penicillin G and oxacillin. Most of MRSA isolates were found to be multi-drug resistant. MRSA alert kit test and mecA and blaZ target gene PCR were found to be useful in the confirmation of MRSA.

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Prevalence, seasonality, and antimicrobial resistance of thermotolerant Campylobacter isolated from broiler farms and slaughterhouses in East Algeria

Veterinary World ◽

10.14202/vetworld.2020.1221-1228 ◽

2020 ◽

Vol 13 (6) ◽

pp. 1221-1228

Author(s):

Mohamed Baali ◽

Mohamed Lounis ◽

Hanan Laidouci Al Amir ◽

Ammar Ayachi ◽

Ahcen Hakem ◽

...

Keyword(s):

Clavulanic Acid ◽

Antimicrobial Agents ◽

Health Hazard ◽

Control Measures ◽

Diffusion Method ◽

Contamination Rate ◽

Isolation And Identification ◽

Initial Finding ◽

Disk Diffusion Method ◽

Amoxicillin Clavulanic Acid

Aim: The current study was carried out to determine the prevalence, seasonality, and antimicrobial profile of thermotolerant Campylobacter isolated from broiler chickens in Batna, East Algeria, from June 2016 to June 2018. Materials and Methods: A total of 960 samples, including 480 cloacal swabs, 240 cecal contents, and 240 neck skin samples collected from 6 poultry farms and 12 slaughterhouses, were included in this study. After isolation and identification, susceptibility to seven antimicrobial agents was tested by the disk diffusion method. The seasonality of Campylobacter infection at broiler farms was statistically analyzed. Results: The data showed that 65%, 55%, and 70% of the cloacal swab, neck skin, and cecal content samples were contaminated with thermotolerant Campylobacter strains, respectively (p<0.05). Among the isolated campylobacteria, Campylobacter jejuni was the predominant species (73.5%). Sampling season exhibited a significant impact on the prevalence of Campylobacter (p<0.01), with peak occurrence in summer. All of the isolates were susceptible to gentamicin and resistant to ampicillin and amoxicillin/clavulanic acid, while 83.3% of them were resistant to erythromycin. Interestingly, 16 different resistance profiles were noted, with the combination of "ampicillin, amoxicillin/clavulanic acid, chloramphenicol, erythromycin, and tetracycline" being the most common, identified in 20.7% of isolated strains. Conclusion: This study demonstrates the presence of a high contamination rate of multidrug-resistant Campylobacter in farms and slaughterhouses in East Algeria. These findings underscore the need to apply strict control measures to avoid any associated public health hazard among Algerian consumers. This initial finding of the contamination of poultry with this zoonotic pathogen in East Algeria suggests the value of periodic comprehensive evaluation of associated disease in poultry as well as in humans in this region.

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Biofilm Formation and its Association with Antibiotic Susceptibility Pattern in Methicillin-resistant Staphylococcus aureus isolates

Journal of Pure and Applied Microbiology ◽

10.22207/jpam.15.4.26 ◽

2021 ◽

Author(s):

Bajarangi Lal Chaudhary ◽

Dakshina Bisht ◽

Sameer Singh Faujdar

Keyword(s):

Staphylococcus Aureus ◽

Biofilm Formation ◽

Methicillin Resistant Staphylococcus Aureus ◽

Antibiotic Sensitivity ◽

Diffusion Method ◽

Beta Lactamase ◽

Isolation And Identification ◽

Methicillin Resistant ◽

Clinical Specimens ◽

Biofilm Production

Methicillin-resistant Staphylococcus aureus is a clinically significant pathogen that causes infections ranging from skin and soft tissue infections to life-threatening sepsis. Biofilm formation by MRSA is one of the crucial virulence factor. Determination of beta-lactamase and biofilm production among Staphylococcus aureus was obtained from various clinical specimens. Standard bacteriological procedures were used for isolation and identification and antibiotic sensitivity was determined using the Kirby Bauer disc diffusion method according to CLSI guidelines. The cloverleaf method, acidometric, iodometric and chromogenic methods were used to detect beta-lactamase while the microtiter plate method and Congo red agar method were used to detect biofilm production. Of the 288 MRSA strains isolated from various clinical specimens,198 (67.07%) were biofilm producers. Cloverleaf and chromogenic (nitrocefin) disc shows 100% results for beta-lactamase detection. Vancomycin was 100% sensitive followed by teicoplanin (92.36%) and linezolid (89.93%). Cloverleaf and nitrocefin disc methods were the most sensitive for detection of beta-lactamase in S. aureus and there was no significant relation between biofilm production and antibiotic sensitivity pattern of S. aureus.

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Profile of antibiotic-resistant and presence of methicillin-resistant Staphylococcus aureus from nasal swab of dogs from several animal clinics in Surabaya, Indonesia

International Journal of One Health ◽

10.14202/ijoh.2020.90-94 ◽

2020 ◽

Vol 6 (1) ◽

pp. 90-94

Author(s):

Vega Decline ◽

Mustofa Helmi Effendi ◽

Reina Puspita Rahmaniar ◽

Sheila Marty Yanestria ◽

Nenny Harijani

Keyword(s):

Staphylococcus Aureus ◽

Antibiotic Resistance ◽

Nasal Swab ◽

Methicillin Resistant Staphylococcus Aureus ◽

Antibiotic Sensitivity ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Antibiotic Resistant ◽

Methicillin Resistant ◽

Oxacillin Resistance

Aim: The research was to investigate the antibiotic resistance profile and to screen for methicillin-resistant Staphylococcus aureus (MRSA) from nasal mucosa swab of dogs. Materials and Methods: The samples were collected from three pet clinics, three K9 units, one veterinary teaching hospital, and one kennel in Surabaya. Of the 50 total samples, 24 confirmed S. aureus strains, which were used for antibiotic sensitivity tests using a disk diffusion method and screening of MRSA used oxacillin resistance screening for base (ORSAB). Results: This study showed that there were differences in antibiotic resistance patterns among different locations. Fourteen isolates were screened for MRSA by culture on ORSAB. Conclusion: MRSA carriage was found on nasal swab of dogs, and dogs can act as reservoir of MRSA for spreading to human health. Keywords: antibiotic-resistant, dogs, methicillin-resistant Staphylococcus aureus, Staphylococcus aureus.

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Antibiotic Molecules Efficacy in Pediatric Bacterial Infections

Revista de Chimie ◽

10.37358/rc.18.4.6227 ◽

2018 ◽

Vol 69 (4) ◽

pp. 915-920

Author(s):

Petronela Cristina Chiriac ◽

Vladimir Poroch ◽

Alina Mihaela Pascu ◽

Mircea Daniel Hogea ◽

Ileana Antohe ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Antibiotic Resistance ◽

Streptococcus Pneumoniae ◽

Klebsiella Pneumoniae ◽

Clavulanic Acid ◽

Bacterial Infections ◽

Multidrug Resistant ◽

Penicillin G ◽

Acute Therapy ◽

Amoxicillin Clavulanic Acid

The antibiotic resistance of microorganisms involved in pediatric infections represents a significant cause of healthcare-associated infections (HAIs), and is also a matter of management, requiring specific intervention. The aim of the study was to evaluate the efficacy of some antibiotic molecules on pathogens isolated from patients admitted in a pediatric hospital. We carried out a descriptive study on a group of 411 patients admitted to the Sf. MariaClinical Emergency Hospital for Children Iasi, between January 1st and March 31st, 2016. Bacterial infections were most prevalent in the age group of 0-1 year (54.98% of the total isolates). Most affected by multidrug-resistant bacterial infections services were: general pediatrics (24.08% of the total isolates), then the intensive care unit (19.95%), surgical wards (14.84%), and acute therapy (11.43%). The germs were isolated from pathological samples: most often pus (23.85%), hypo-pharyngeal aspiration (21.65%), conjunctival secretion (12.42%), and ear secretion (9.48%). Penicillin G and oxacillin were inefficient in 30.26% of the Staphylococcus aureus strains, while erythromycin in 18.42%. Antibiotic resistance of Streptococcus pneumoniae was observed for penicillin G in 7.14% of the strains, while for erythromycin in 13.09%. Klebsiella pneumoniae strains were resistant to amoxicillin + clavulanic acid in 35.85% of the cases, and to cefuroxime, ceftazidime, ceftriaxone, cefepime in 33.96%. Our study highlighted that Staphylococcus aureus was resistant to penicillin G and oxacillin in more than one-third of the isolates, Streptococcus pneumoniae was resistant to penicillin G and erythromycin, and Klebsiella pneumoniae to amoxicillin + clavulanic acid and 1st, 2nd and 3rd generation cephalosporins. Continuing antibioresistance monitoring is crucial in order to promote appropriate guidelines in antibiotic prescription, which could result in decreasing HAIs� rates.

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