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

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.

Download Full-text

Prevalence, Antibiogram, and cdt Genes of Toxigenic Campylobacter jejuni in Salad Style Vegetables (Ulam) at Farms and Retail Outlets in Terengganu

Journal of Food Protection ◽

10.4315/0362-028x.jfp-14-109 ◽

2015 ◽

Vol 78 (1) ◽

pp. 65-71 ◽

Cited By ~ 7

Author(s):

MOHD IKHSAN KHALID ◽

JOHN YEW HUAT TANG ◽

NABILA HUDA BAHARUDDIN ◽

NASIHA SHAKINA RAHMAN ◽

NURUL FAIZZAH RAHIMI ◽

...

Keyword(s):

Antibiotic Resistance ◽

Multiplex Pcr ◽

Campylobacter Jejuni ◽

Antibiotic Susceptibility ◽

Penicillin G ◽

Diffusion Method ◽

Cytolethal Distending Toxin ◽

Disk Diffusion Method ◽

Retail Outlets ◽

Pcr Method

The present study was conducted to investigate the prevalence and antibiotic resistance among Campylobacter jejuni in ulam at farms and retail outlets located in Kuala Terengganu, Malaysia. A total of 526 samples (ulam, soil, and fertilizer) were investigated for the presence of C. jejuni and the gene for cytolethal distending toxin (cdt) by using a multiplex PCR method. Antibiotic susceptibility to 10 types of antibiotics was determined using the disk diffusion method for 33 C. jejuni isolates. The average prevalence of contaminated samples from farms, wet markets, and supermarkets was 35.29, 52.66, and 69.88%, respectively. The cdt gene was not detected in 24 of the 33 C. jejuni isolates, but 9 isolates harbored cdtC. Antibiotic resistance in C. jejuni isolates was highest to penicillin G (96.97% of isolates) followed by vancomycin (87.88%), ampicillin (75.76%), erythromycin (60.61%), tetracycline (9.09%), amikacin (6.06%), and norfloxacin (3.03%); none of the isolates were resistant to ciprofloxacin, enrofloxacin, and gentamicin. In this study, C. jejuni was present in ulam, and some isolates were highly resistant to some antibiotics but not to quinolones. Thus, appropriate attention and measures are required to prevent C. jejuni contamination on farms and at retail outlets.

Download Full-text

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

Pakistan Journal of Medical Sciences ◽

10.12669/pjms.37.5.4274 ◽

2021 ◽

Vol 37 (5) ◽

Author(s):

Selim Görgün ◽

Hacer İşler ◽

Mehmet Cenk Turgut

Keyword(s):

Methicillin Resistance ◽

Meca Gene ◽

Latex Agglutination ◽

Disk Diffusion ◽

Diffusion Method ◽

Chain Reaction ◽

Disk Diffusion Method ◽

Chromogenic Agar ◽

Pcr Method ◽

Conventional Methods

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.

Download Full-text

Evaluation of Antibiotic Susceptibility Pattern and Distribution of coa Genes in Coagulase-negative S. aureus from Ahvaz, Iran

Infectious Disorders - Drug Targets ◽

10.2174/1871526518666180816101629 ◽

2019 ◽

Vol 19 (4) ◽

pp. 383-387

Author(s):

Saeed Shahmohammadi ◽

Ahmad Farajzadeh Sheikh ◽

Mojtaba Shahin ◽

Iman Mir

Keyword(s):

Antibiotic Susceptibility ◽

Meca Gene ◽

Diffusion Method ◽

Susceptibility Pattern ◽

Disk Diffusion Method ◽

Antibiotic Resistant ◽

Antibiotic Susceptibility Pattern ◽

Appropriate Treatment ◽

Pcr Method ◽

Southwest Of Iran

Background: Staphylococcus aureus is one of the important causes of clinical infections that can be more destructive by its antibiotic resistant strains. Objective: This study aimed to determine the antibiotic susceptibility pattern and distribution of mecA and coa genes in clinical isolates of S. aureus. Methods: Two hundred seventy-three specimens suspected to S. aureus were taken from hospitals of Ahvaz, southwest of Iran. Isolates were identified by standard microbiologic tests and confirmed by the molecular method. Antimicrobial susceptibility testing was carried out by disk diffusion method. The presence of mecA and coa genes was determined by PCR method. Results: Of a total of 200 isolates which were tested for coagulase tube test, 143 (71.5%) showed coagulase positive, and 57 (28.5%) showed a coagulase-negative reaction. Antibacterial susceptibility pattern of 200 S. aureus isolates showed the highest and lowest susceptibility rate to linezolid (98%) and ciprofloxacin (42%), respectively. The prevalence of methicillin-resistant S. aureus (MRSA) by detection of mecA gene was estimated as 47.5 % (95/200), of which the rate of MRSA in coagulase positive and negative isolates was 35% (50/143), and 65% (45/57), respectively. Meanwhile, coa gene was detected in 100% of coagulase positive and 28.1% of coagulasenegative isolates. Conclusion: The results of this study showed that the number of atypical CNSA in our area is high. Since the coagulase test is an essential test for diagnosis of S. aureus, our findings regarding the emergence of CNSA are a warning about the misdiagnosis and selection of appropriate treatment approach for S. aureus isolates.

Download Full-text

Prevalence of SHV-extended spectrum β-lactamase producing carbapenem –resistantKlebsiellapneumoniae among patients with lower respiratory tractinfections in Babylon Province-Iraq.

International Journal of Research in Pharmaceutical Sciences ◽

10.26452/ijrps.v9ispl1.1299 ◽

2018 ◽

Vol 9 (SPL1) ◽

Author(s):

Fatima Moeen Abbas

Keyword(s):

Resistance Rate ◽

Combination Method ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Carbapenem Resistant ◽

Extended Spectrum ◽

Pcr Method ◽

Polymerase Chain ◽

Tract Infections ◽

Positive Results

This study was carried out to screen the prevalence of Klebsiella pneumoniae isolated from patients with lower respiratory tract infections in Babylon province.From December,2015 to the end of March,2016,a total of 100 sputum samples were collected from patients visited or hospitalized Merjan Teaching Hospital and Al- Hashimya General Hospital. Fifteenth (65%) isolates were identified as Klebsiellapneumoniae. All bacterial isolates were evaluated for extended spectrum β-lactamase (ESBL) production phenotypically using disk combination method. Eleven (73.3%) isolates were detected as ESBL-producers. Kirby-Bauer disk diffusion method was employed to determine resistance profile of ESBLs-positive isolates. Higher rates of resistance were observed for ampicillin and piperacillin antibiotics with (81.8%) and (72.7%) resistance rate, respectively, while the lowest rate was noticed for imipenem antibiotic (14.28%). Carbapenem-resistant isolates were investigated for blaSHV gene by Polymerase Chain Reaction (PCR) method, 2 (100%) isolates gave positive results.

Download Full-text

Preliminary Results on the Prevalence of Salmonella Spp. in Marine Animals Stranded in Sicilian Coasts: Antibiotic Susceptibility Profile and ARGs Detection in the Isolated Strains

Pathogens ◽

10.3390/pathogens10080930 ◽

2021 ◽

Vol 10 (8) ◽

pp. 930

Author(s):

Delia Gambino ◽

Sonia Sciortino ◽

Sergio Migliore ◽

Lucia Galuppo ◽

Roberto Puleio ◽

...

Keyword(s):

Antibiotic Resistance ◽

Resistance Genes ◽

Antibiotic Susceptibility ◽

Antibiotic Resistance Genes ◽

Diffusion Method ◽

Salmonella Spp ◽

Marine Animals ◽

Disk Diffusion Method ◽

Phenotypic Resistance ◽

Low Prevalence

The presence of Salmonella spp. in marine animals is a consequence of contamination from terrestrial sources (human activities and animals). Bacteria present in marine environments, including Salmonella spp., can be antibiotic resistant or harbor resistance genes. In this study, Salmonella spp. detection was performed on 176 marine animals stranded in the Sicilian coasts (south Italy). Antibiotic susceptibility, by disk diffusion method and MIC determination, and antibiotic resistance genes, by molecular methods (PCR) of the Salmonella spp. strains, were evaluated. We isolated Salmonella spp. in three animals, though no pathological signs were detected. Our results showed a low prevalence of Salmonella spp. (1.7%) and a low incidence of phenotypic resistance in three Salmonella spp. strains isolated. Indeed, of the three strains, only Salmonella subsp. enterica serovar Typhimurium from S. coeruleoalba and M. mobular showed phenotypic resistance: the first to ampicillin, tetracycline, and sulphamethoxazole, while the latter only to sulphamethoxazole. However, all strains harbored resistance genes (blaTEM, blaOXA, tet(A), tet(D), tet(E), sulI, and sulII). Although the low prevalence of Salmonella spp. found in this study does not represent a relevant health issue, our data contribute to the collection of information on the spread of ARGs, elements involved in antibiotic resistance, now considered a zoonosis in a One Health approach.

Download Full-text

β-lactam resistance in bacteria associated with subclinical mastitis in goats in Thika Subcounty, Kenya

Veterinary World ◽

10.14202/vetworld.2020.1448-1456 ◽

2020 ◽

Vol 13 (7) ◽

pp. 1448-1456

Author(s):

Irene Mkavi Okoko ◽

Naomi Maina ◽

Daniel Kiboi ◽

John Kagira

Keyword(s):

Risk Factors ◽

Antibiotic Resistance ◽

Subclinical Mastitis ◽

Penicillin G ◽

Confirmatory Test ◽

Diffusion Method ◽

Dairy Goats ◽

Isolation And Identification ◽

Factors Associated ◽

Synergy Test

Aim: This study determined the resistance pattern to β-lactam antibiotics of bacteria isolated from goats with subclinical mastitis in Thika subcounty, Kenya. We also administered a questionnaire to assess the risk factors associated with the occurrence of resistance to commonly used antibiotics. Materials and Methods: We collected milk samples from 110 lactating dairy goats in Thika subcounty to screen for subclinical mastitis using the California mastitis test. Bacterial isolation and identification were performed according to colony morphology, the hemolytic pattern on sheep blood agar, lactose fermentation on MacConkey plates, Gram staining, and standard biochemical tests. The antibiotic susceptibility of the isolates was determined by the agar disk diffusion method using penicillin G, cephalexin, cefoxitin, and cefotaxime antibiotic disks. The double-disk synergy test using amoxicillin-clavulanic acid was employed as a confirmatory test for extended-spectrum β-lactamase (ESBL) production. Fisher's exact test was used to determine the risk factors associated with the occurrence of antibiotic resistance (p≤0.05 was considered significant). Results: Of the 110 dairy goats sampled, 72.7% (80) were positive for subclinical mastitis. Isolation and identification of the bacteria from the positive samples yielded 149 bacteria isolates, including Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter spp., Yersinia spp., coagulase-negative staphylococci, and Escherichia coli. A high percentage (76.5%, 114/149) of the bacterial isolates was resistant to at least one of the tested antibiotics. At least 56/106 isolates (52.8%) showing cross-resistance to the β-lactam antibiotics were resistant to all four of the tested antibiotics, while only one isolate was resistant to three antibiotics (penicillin G, cephalexin, and cefoxitin). The double-disk synergy test confirmed that none of the isolates possessed ESBLs. Pre- and post-milking practices (p=0.0336) were found to be significantly associated with the occurrence of antibiotic resistance. Conclusion: A large proportion of the goats in our study cohort were infected with β-lactam-resistant bacteria associated with subclinical mastitis. Because the identified bacteria are of zoonotic importance, further studies should be undertaken to determine the transmission dynamics between humans and livestock and to identify novel intervention strategies.

Download Full-text

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.

Download Full-text

Prevalence and Antibiograms of Salmonella in Commercially Produced Crocodile meat in Zimbabwe

Tanzania Veterinary Journal ◽

10.4314/tvj.v36i1.1 ◽

2021 ◽

Vol 36 (1) ◽

pp. 1-14

Author(s):

A.Z. Nhidza ◽

C. Gufe ◽

J. Marumure ◽

Z. Makuvara ◽

T. Chisango ◽

...

Keyword(s):

Hazard Analysis ◽

Control Point ◽

Penicillin G ◽

Diffusion Method ◽

Biochemical Tests ◽

Disk Diffusion Method ◽

Critical Control Point ◽

Meat Samples ◽

Low Prevalence ◽

Susceptibility Profiles

The presence of Salmonella in food products and emergence of antibiotic resistance are the major challenges facing public health policies. A total of 2749 crocodile meat samples obtained from the Central Veterinary Laboratories in Zimbabwe were screened for Salmonella specieswere collected from three Zimbabwean commercial farms between the year 2012 and 2019 for a retrospective observational study to determine the prevalence and magnitude of antibiotics resistant Salmonella species in crocodile meat. The isolation of Salmonella was in accordance with the ISO 6579:2002 and the antibiotic susceptibility testing was carried out based on Clinical and Laboratory Standard Institute’s recommendations by means of the Kirby-Bauer disk diffusion method. SILAB Database was used to determine the prevalence of Salmonella species. Prevalence was stratified by year and farms. Twenty Salmonella isolates were identified using biochemical tests, and 15 were confirmed by polymerase chain reaction (PCR). Antimicrobial susceptibility profiles of the confirmed Salmonella isolates were examined using 14 antibiotics. The overall prevalence of Salmonella species in crocodile meat samples was 0.5%. The prevalence of Salmonella species ranged from 0.04% to 0.44% in the crocodile meat samples and annual prevalence ranged from 0.01% to 1%. The highest prevalence of Salmonella (4.4%) was recorded in the year 2012. Salmonella isolates from one of the three tested farms were resistant to Erythromycin (73.33%), Ampicillin (80%), and Penicillin G (100%). Generally, Salmonella isolates displayed lower resistance to Cefepime, Ceftriaxone, Amikacin, Tetracycline, Ertapenem, Florfenicol, and Erythromycin (0-53.33%) whereas all Salmonella isolates showed susceptibility to Cefepime, Ceftriaxone, Ertapenem, and Florfenicol. Although the study indicates low prevalence of Salmonella species in crocodile meat, there is a need for strict implementation of Hazard Analysis Critical Control Point (HACCP) to reduce contamination rates in meat and its products

Download Full-text

Molecular Detection and Antibiotyping of Multidrug-Resistant Salmonella Isolated from Houseflies in a Fish Market

Pathogens ◽

10.3390/pathogens8040191 ◽

2019 ◽

Vol 8 (4) ◽

pp. 191 ◽

Cited By ~ 5

Author(s):

Sobur ◽

Hasan ◽

Haque ◽

Mridul ◽

Noreddin ◽

...

Keyword(s):

Molecular Detection ◽

Multidrug Resistant ◽

Diffusion Method ◽

Resistant Bacteria ◽

Salmonella Spp ◽

Disk Diffusion Method ◽

Antibiotic Resistant ◽

Fish Market ◽

Pcr Method ◽

High Level

Houseflies (Musca domestica) are well-known mechanical vectors for spreading multidrug-resistant bacteria. Fish sold in open markets are exposed to houseflies. The present study investigated the prevalence and antibiotypes of multidrug-resistant (MDR) Salmonella spp. in houseflies captured from a fish market. Direct interviews with fish vendors and consumers were also performed to draw their perceptions about the role of flies in spreading antibiotic-resistant bacteria. A total of 60 houseflies were captured from a local fish market in Bangladesh. The presence of Salmonella spp. was confirmed using PCR method. Antibiogram was determined by the disk diffusion method, followed by the detection of tetA, tetB, and qnrA resistance genes by PCR. From the interview, it was found that most of the consumers and vendors were not aware of antibiotic resistance, but reported that flies can carry pathogens. Salmonella spp. were identified from the surface of 34 (56.7%) houseflies, of which 31 (91.2%) were found to be MDR. This study revealed 25 antibiotypes among the isolated Salmonella spp. All tested isolates were found to be resistant to tetracycline. tetA and tetB were detected in 100% and 47.1% of the isolates, respectively. Among the 10 isolates phenotypically found resistant to ciprofloxacin, six (60%) were found to be positive for qnrA gene. As far as we know, this is the first study from Bangladesh to report and describe the molecular detection of multidrug-resistant Salmonella spp. in houseflies in a fish market facility. The occurrence of a high level of MDR Salmonella in houseflies in the fish market is of great public health concerns.

Download Full-text

Prevalence of Plasmid-Mediated Quinolone Resistance Genes among Extended-Spectrumβ-Lactamase-ProducingKlebsiella pneumoniaeHuman Isolates in Iran

Journal of Pathogens ◽

10.1155/2015/434391 ◽

2015 ◽

Vol 2015 ◽

pp. 1-7 ◽

Cited By ~ 15

Author(s):

Ehsaneh Shams ◽

Farzaneh Firoozeh ◽

Rezvan Moniri ◽

Mohammad Zibaei

Keyword(s):

Klebsiella Pneumoniae ◽

Resistance Genes ◽

High Frequency ◽

Quinolone Resistance ◽

Confirmatory Test ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Pcr Products ◽

Pcr Method

The purpose of this study was to determine the prevalence and molecular characterization of plasmid-mediated quinolone resistance (PMQR) genes (qnrA, qnrB, qnrS, aac(6′)-Ib-cr, andqepA) among ESBL-producingKlebsiella pneumoniaeisolates in Kashan, Iran. A total of 185K. pneumoniaeisolates were tested for quinolone resistance and ESBL-producing using the disk diffusion method and double disk synergy (DDST) confirmatory test. ESBL-producing strains were further evaluated for theblaCTX-Mgenes. The PCR method was used to show presence of plasmid-mediated quinolone resistance genes and the purified PCR products were sequenced. Eighty-seven ESBL-producing strains were identified by DDST confirmatory test and majority (70, 80.5%) of which carriedblaCTX-Mgenes including CTX-M-1 (60%), CTX-M-2 (42.9%), and CTX-M-9 (34.3%). Seventy-seven ESBL-producingK. pneumoniaeisolates harbored PMQR genes, which mostly consisted ofaac(6′)-Ib-cr(70.1%) andqnrB(46.0%), followed byqnrS(5.7%). Among the 77 PMQR-positive isolates, 27 (35.1%) and 1 (1.3%) carried 2 and 3 different PMQR genes, respectively. However,qnrAandqepAwere not found in any isolate. Our results highlight high ESBL occurrence with CTX-M type and high frequency of plasmid-mediated quinolone resistance genes among ESBL-producingK. pneumoniaeisolates in Kashan.

Download Full-text