Screening for oxacillin resistant salmonella species isolated from palms of some primary school pupils within Kaduna south lga, Nigeria

Salmonella species is the causative agent of typhoid fever which is a disease characterized by high mortality and morbidity worldwide. This study was carried out to screen oxacillin resistantSalmonella species isolated from palms of some primary school pupils and food vendors within Kaduna South LGA, Nigeria. Three hundred (300) swab samples were collected from pupils and food vendors of the three selected primary schools as the sampling location. Salmonella enterica was isolated and identified using standard bacteriological methods. Isolates were susceptible to ciprofloxacin 28 (70.0%), Augmentin® 25 (65.0%) amoxicillin 25 (62.5%) and vancomycin 22 (55.0%) but showed resistance to oxacillin 9 (22.5%), ampicillin 12 (30.0%), chloramphenicol 15 (37.5%) and tetracycline 16 (40.0%). Antibiotics that exhibited intermediate susceptibility were methicillin 8 (20.0%) and gentamicin 11 (27.5%). Ciprofloxacin was the most effective antimicrobial agent against Salmonella enterica. The presence of oxacillin-resistant Salmonella enterica was detected via Polymerase Chain Reaction (PCR) and agarose gel electrophoresis. The study recommends that regular monitoring of antibiotic susceptibility pattern and good hygiene practices such as hand washing with soap and water and the use of alcoholic based hand sanitizers should be encouraged.

Phenotypic and genotypic characterization of oxacillin-susceptible and mecA positive Staphylococcus aureus strains isolated in Uruguay / Caracterización fenotípica y genotípica de cepas de Staphylococcus aureus sensibles a oxacilina y mecA positivas aisladas en Uruguay

Abstract The aim of this study was to characterize phenotypically and genotypically 27 mecApositive Staphylococcus aureus strains with oxacillin MICs of ≤2 g/ml by Vitek 2, isolated indifferent regions of Uruguay. Susceptibility to oxacillin and cefoxitin was studied by gradient dif-fusion, disk diffusion to cefoxitin, and Phoenix and MicroScan systems. PBP2a was determined.SCCmec typing was performed and the isolates were compared by PFGE. Twenty-six isolateswere susceptible to oxacillin; one strain was susceptible to cefoxitin by disk diffusion and 3strains by gradient diffusion. Phoenix and MicroScan panels detected methicillin resistance in25 and 27 strains, respectively. Twenty-six strains tested positive for PBP2a. Twenty-six strainscarried SCCmec V and 24 belonged to pulsotype A. One strain carried SCCmec IV and did notbelong to pulsotype A. Cefoxitin disk diffusion test and PBP2a detection correctly identified 26of these 27 strains as MRSA. PFGE results suggest the dissemination of a cluster of MRSA carryingSCCmec V.

Resumen El objetivo de este estudio fue caracterizar fenotípicamente y genotípicamente 27 cepas de Staphylococcus aureus positivas para mecA y con CIM de oxacilina <2 pg/ml según Vitek 2, obtenidas en diferentes regiones del país. La sensibilidad frente a la oxacilina y la cefoxitina se estudió por difusión en gradiente, por disco-difusión (cefoxitina) y por los sistemas Phoenix y MicroScan. Se analizó la portación de PBP2a, se realizó la tipificación de SCCmec y las cepas se compararon mediante PFGE. Resultaron sensibles a oxacilina por difusión en gradiente 26 cepas; una fue sensible a cefoxitina por disco-difusión y 3 lo fueron por difusión en gradiente. Los sistemas Phoenix y MicroScan detectaron resistencia a meticilina en 25 y 27 cepas, respectivamente. Asimismo, 26 cepas portaban PBP2a y 26 cepas mostraron presencia de SCCmec V, 24 correspondieron al pulsotipo A. Una portaba SCCmec IV y no perteneció al pulsotipo A. La prueba de disco-difusión con cefoxitina y la detección de PBP2a identificaron 26 de 27 cepas como MRSA. La PFGE sugiere la diseminación de un grupo MRSA con SCCmec V. © 2022 Asociación Argentina de Microbiología. Publicado por Elsevier Espana, S.L.U. Este es un artículo Open Access bajo la licencia CC BY-NC-ND (https://creativecommons.org/licenses/by-nc-nd/4.0/).

Chemical composition and antimicrobial activity of two extract of propolis against isolates of Staphylococcus spp. and multiresistant bacterials / Composição química e atividade antimicrobiana de dois extratos de própolis contra isolados de Staphylococcus spp. e bactérias multirresistentes

There is a growing need to discover and develop alternative therapies for the treatment of mastitis caused by Staphylococcus spp. and multidrug-resistant bacterial infections. This study examined the chemical composition and antimicrobial potential of two propolis extracts (EPA and EPB) against seventy-seven isolates of Staphylococcus spp. obtained from subclinical bovine mastitis; three clinical strains of MRSA and two from clinical strains of S. aureus ATCC, identified as S. aureus ATCC 6538 and S. aureus ATCC 25923. The total phenolic content was determined by the Folin-Ciocalteau method, the total flavonoid content by the Dowd method and the phenolic profile was quantified by HPLC-DAD. The MBC values of the extracts were evaluated by broth microdilution method. The amount of total phenolic and flavonoid compounds was higher in EPA than EPB. Both extracts revealed the presence of caffeic, coumaric, cinnamic, ferulic and 3,4-dihydroxybenzoic acids, with higher concentrations of coumaric and cinnamic acids. Staphylococcus spp. isolates were susceptible to EPA (90.9%), EPB (83.1%) and oxacillin (80.5%). The oxacillin susceptible isolates were also susceptible to EPA (70.1%) and EPB (80.6%), whereas those oxacillin-resistant strains were also susceptible to EPA (40.0%) and to EPB (26.7%). MBC ranged from 34.3 to 68.7µm/mL for EPA and from 68.7 to 137.5µg/mL for EPB. Both extracts inhibited significantly (100%) the clinical strains of MRSA, S. aureus ATCC 6538 and S. aureus ATCC 25923 at the concentration of 68.7µg/mL. It is concluded that both extracts of propolis, whose main constituents are coumaric and cinnamic acids, have high antimicrobial activity against the microorganisms studied, and EPA also against oxacillin-resistant strains. These findings reinforce its potential use for the treatment of bovine mastitis.(AU)

É cada vez mais oportuna a necessidade de descobrir e desenvolver terapias alternativas para tratamento da mastite causada por Staphylococcus spp. e de infecções bacterianas multirresistentes. Este estudo examinou a composição química e o potencial antimicrobiano de dois extratos etanólicos de própolis (EPA e EPB) contra setenta e sete isolados de Staphylococcus spp. obtidos a partir de mastite bovina subclínica; três estirpes clínicas de MRSA e duas de linhagens clínicas de S. aureus ATCC, identificadas como, S. aureus ATCC 6538 e S. aureus ATCC 25923, ambas metacilina resistentes. O teor total de fenólicos foi determinado pelo método de Folin-Ciocalteau, o teor de flavonoides totais pelo método Dowd e o perfil fenólico foi quantificado por HPLC-DAD. CBM dos extratos foi avaliada pelo método de microdiluição em caldo. A quantidade total de compostos fenólicos e flavonoides foi maior no EPA do que no EPB. Ambos os extratos revelaram a presença dos ácidos cafeico, cumárico, cinâmico, ferúlico e 3,4-di-hidroxibenzóico, com maiores concentrações de ácidos cumárico e cinâmico. Os isolados de Staphylococcus spp. foram sensíveis a EPA (90,9%), EPB (83,1%) e oxacilina (80,5%). Os isolados suscetíveis à oxacilina também foram suscetíveis ao EPA (70,1%) e ao EPB (80,6%), enquanto os do resistente à oxacilina foram suscetíveis ao EPA (40,0%) e ao EPB (26,7%). MBC variou de 34,3 a 68,7µm/mL para EPA e de 68,7 a 137,5µg/mL para EPB. Ambos os extratos inibiram significativamente (100%) as linhagens clínicas de MRSA, S. aureus ATCC 6538 e S. aureus ATCC 25923 na concentração de 68,7µg/mL. Conclui-se que os extratos etanólicos da própolis, cujos principais constituintes são os ácidos cumário e cinâmico, possuem atividade antimicrobiana contra os micro-organismos estudados, e o EPA também contra as cepas resistentes à oxacilina. Estes achados reforçam seu potencial uso para o tratamento da mastite bovina.(AU)

Isoenzyme genotyping and phylogenetic analysis of oxacillin-resistance Staphylococcus aureus isolates

Aim: The propagation of S. aureus in hospital and dental environments is considered an important public health problem since resistant strains can cause serious infections in humans. The genetic variability of 99 oxacillin-resistant S. aureus isolates (ORSA) from the dental patients (oral cavity) and environments (air) was studied by isoenzyme genotyping. Methods: S. aureus isolates were studied using isoenzyme markers (alcohol dehydrogenase, sorbitol dehydrogenase, mannitol-1-phosphate dehydrogenase, malate dehydrogenase, glucose dehydrogenase, D-galactose dehydrogenase, glucose-6-phosphate dehydrogenase, catalase and α/ß-esterase) and genetic (Nei's statistics) and cluster analysis (UPGMA algorithm). Results: A highly frequent polyclonal pattern was observed in this population of ORSA isolates, suggesting various sources of contamination or microbial dispersion. Genetic relationship analysis showed a high degree of polymorphism between the strains, and it revealed three taxa (A, B and C) distantly genetically related (0.653≤dij≤1.432) and fifteen clusters (I to XV) moderately related (0.282≤dij<0.653). These clusters harbored two or more highly related strains (0≤dij<0.282), and the existence of microevolutionary processes in the population of ORSA. Conclusion: This research reinforces the hypothesis of the existence of several sources of contamination and/or dispersal of ORSA of clinical and epidemiologically importance, which could be associated with carriers (patients) and dental environmental (air) (AU)

Staphylococcus aureus con resistencia múltiple a los antibióticos (MDR) en un Hospital de Maracaibo- Venezuela / Multidrug-resistant (MDR) Staphylococcus aureus in a Maracaibo’s hospital, Venezuela

Staphylococcus aureus resistente a oxacilina (SAOR) continúa siendo una causa importante de infecciones nosocomiales en todo el mundo. Se determinó la resistencia a los antibióticos de cepas intrahospitalarias, clasificándolas en multidrogo-resistentes, extensamente drogo-resistentes o pandrogo-resistentes. Las muestras biológicas fueron recolectadas entre septiembre 2013-febrero 2014 y procesadas de acuerdo a técnicas de bacteriología convencional. La resistencia a los antibióticos se determinó mediante el método de difusión con discos en agar y el gen mecA se detectó mediante reacción en cadena de la polimerasa. Se observó baja prevalencia de SAOR intrahospitalario (13,86%). La mayor resistencia fue a eritromicina (66,07%), mientras que la resistencia frente a aminoglucósidos, fluoroquinolonas, clindamicina y tetraciclina fue inferior al 25%; la resistencia frente a trimetoprim/sulfametoxazol fue muy baja y el 100% de las cepas mostraron sensibilidad a rifampicina, linezolid, vancomicina y teicoplanina. El fenotipo de resistencia a MLSB más frecuente fue el de resistencia a eritromicina y susceptibilidad a clindamicina (33,93%, fenotipo MSB). Las cepas SAOR aisladas presentaron 25 antibiotipos diferentes, siendo la mayoría de los aislamientos multidrogo-resistentes (55,36%). No se observó resistencia extensa a los antibióticos ni pandrogo-resistencia y la presencia del gen mecA se demostró en todos los aislamientos resistentes a oxacilina.

Oxacillin-resistant Staphylococcus aureus (ORSA) has remained a major cause of nosocomial infections worldwide. The antibiotic resistance of isolations was determined and we classify them in multidrug-resistant, extensively drug-resistant or pandrug-resistant. The biological samples of patients from a Maracaibo’s Hospital, during September 2013 to February 2014, were processed according to conventional techniques of bacteriology. Antibiotic resistance was determined by disk diffusion method in agar and the mecA gene was detected by polymerase chain reaction. It was observed a low prevalence of nosocomial ORSA (13.86%). The higher antibiotic resistance was observed against erythromycin (66.07%) and a resistance lower than 25% to aminoglycosides, fluoroquinolones, tetracycline and clindamycin. The isolates showed a very low resistance to trimethoprim/sulfamethoxazole and all isolates were susceptible to rifampicin, linezolid, vancomycin and teicoplanin.The majority of isolates had a MSB phenotype (33.93%), with erythromycin resistance and susceptibility to clindamycin. The ORSA isolates in this study had 25 different antibiotypes and the majority of them were multidrug-resistant (55.36%). There was not both extensively drug-resistant and pandrug-resistant isolates and the presence of the mecA gene was demonstrated in all isolates of ORSA.

Utilização de PCR-multiplex para identificação de Staphylococcus aureus e avaliação da resistência à oxacilina e mupirocina / Multiplex PCR use for Staphylococcus aureus identification and oxacillin and mupirocin resistance evaluation

Oxacillin-resistant Staphylococcus aureus represents a serious problem in hospitals worldwide, increasing infected patients? mortality and morbidity and raising treatment costs and internment time. In this study, the results of using the Multiplex PCR technique to amplify fragments of the genes femA (specific-species), mecA (oxacillin resistance) and ileS-2 (mupirocin resistance) were compared with those of tests conventionally used to identify S. aureus isolates and ascertain their resistance to drugs. Fifty S. aureus strains were isolated from patients receiving treatment at UNOESTE University Hospital in Presidente Prudente, SP, Brazil. The 686 bp fragment corresponding to the gene femA was amplified and detected in all the isolates. On the other hand, the 310 bp fragment corresponding to the mecA gene was amplified in 29 (58%) of the isolates. All of the isolates showed sensitivity to mupirocin in the agar diffusion test, which was corroborated by the lack of any amplicon of the 456 bp fragment corresponding to the ileS-2 gene, in the PCR bands. The conventional tests to identify S. aureus and detect resistance to oxacillin and mupirocin showed 100% agreement with the PCR Multiplex results. The use of techniques for rapid and accurate identification of bacteria and assessment of their resistance may be valuable in the control of infection by resistant strains, allowing the rapid isolation and treatment of an infected patient. However, the results demonstrate that traditional phenotypic tests are also reliable, though they take more time.

Staphylococcus aureus resistente à oxacilina representa um problema grave em hospitais de todo o mundo, aumentando a morbidade e mortalidade de pacientes infectados e, elevando os custos do tratamento e tempo de internação. Neste trabalho, foram comparados os resultados da técnica de PCR Multiplex para amplificação dos fragmentos dos genes femA (espécie-específico), mecA (resistência à oxacilina) e ileS-2 (resistência à mupirocina) com os resultados da identificação e testes convencionais para avaliação da resistência. Cinqüenta S. aureus foram isolados de pacientes atendidos no Hospital Universitário "Dr. Domingos Leonardo Cerávolo" da Unoeste, em Presidente Prudente, SP, Brasil. Houve amplificação do fragmento 686 pb, correspondente ao gene femA para todos os isolados. Por outro lado, houve amplificação do fragmento 310 pb correspondente ao gene mecA em 29 (58%) dos isolados. Todos os isolados mostraram sensibilidade à mupirocina observados no teste da difusão em ágar, e também pela ausência de amplificação do fragmento 456 pb, correspondente ao gene ileS-2. Os resultados dos testes convencionais para identificação de S. aureus e avaliação de resistência à oxacilina e mupirocina mostrou 100% de concordância com os resultados da PCR Multiplex. A utilização de técnicas mais rápidas e precisas para identificação e avaliação de resistência pode ser valiosa para o controle de infecção por cepas resistentes, permitindo rápido isolamento e tratamento do paciente. Entretanto os resultados demonstram que testes fenotípicos tradicionais também são confiáveis, apesar do maior tempo de execução.

Oxacillin Resistance in 175 Clinical Staphylococcus aureus Strains / 中华医院感染学杂志

OBJECTIVE To study the incidence of ?-lactamases and oxacillin-resistant Staphylococcus aureus and their drug resistance in our hospital. METHODS The clinical isolates were identified by VITEK-60 of Bio-Merieux of France. K-B agar diffusion method and confirmed test were used to detect the drug resistance of oxacillin-resistant S. aureus. RESULTS Among 175 S. aureus isolates, the incidence of ?-lactamases was 94.3% and the incidence of oxacillin-resistant S. aureus was 28.6%. Oxacillin-resistant S. aureus was mostly isolated from pus/wound (52.0%), then from sputum and throat swab (32.0%). CONCLUSIONS To cure infections caused by ?-lactamases-noproducing S. aureus, penicillin is the best choice. For infections caused by ?-lactamases-producing but oxacillin sensitive S. aureus, the first generation cephalosporins are the best choice, while curing infections caused by ?-lactamases-producing and oxacillin- resistanct, S. aureus nitrofurantoin and linezolid are the best choice. The resistance rate to vancomycin is zero. It should be carefully used in therapy.