Community-genotype methicillin-resistant Staphylococcus aureus skin and soft tissue infections in Latin America: a systematic review

ABSTRACT Background: Community-genotype methicillin-resistant Staphylococcus aureus (CG-MRSA) emerged in the 1990s as a global community pathogen primarily involved in skin and soft tissue infections (SSTIs) and pneumonia. To date, the CG-MRSA SSTI burden in Latin America (LA) has not been assessed. Objective: The main objective of this study was to report the rate and genotypes of community-genotype methicillin-resistant Staphylococcus aureus (CG-MRSA) causing community-onset skin and soft tissue infections (CO-SSTIs) in LA over the last two decades. In addition, this research determined relevant data related to SSTIs due to CG-MRSA, including risk factors, other invasive diseases, and mortality. Data sources: Relevant literature was searched and extracted from five major databases: Embase, PubMed, LILACS, SciELO, and Web of Science. Methods: A systematic review was performed, and a narrative review was constructed. Results: An analysis of 11 studies identified epidemiological data across LA, with Argentina presenting the highest percentage of SSTIs caused by CG-MRSA (88%). Other countries had rates of CG-MRSA infection ranging from 0 to 51%. Brazil had one of the lowest rates of CG-MRSA SSTI (4.5-25%). In Argentina, being younger than 50 years of age and having purulent lesions were predictive factors for CG-MRSA CO-SSTIs. In addition, the predominant genetic lineages in LA belonged to sequence types 8, 30, and 5 (ST8, ST30, and ST5). Conclusion: There are significant regional differences in the rates of CG-MRSA causing CO-SSTIs. It is not possible to conclude whether or not CG-MRSA CO-SSTIs resulted in more severe SSTI presentations or in a higher mortality rate.

Molecular characteristics of methicillin-resistant Staphylococcus aureus isolates from hospital and community environments in northeastern Brazil

ABSTRACT This study characterized 30 MRSA isolates from intensive care unit (ICU) environment and equipment surfaces and healthy children. The SCCmec types I, IVa and V were detected in HA-MRSA isolates while CA-MRSA showed the SCCmec type IVa and V. Most isolates were classified as agr group II. All isolates presented the sei gene, and only HA-MRSA were positive for etb e tst genes. Three genotypes were related to Pediatric (ST5/SCCmecIV) and Berlin (ST45/SCCmecIV) clones. The present study showed molecular similarity between CA- and HA-MRSA isolates in hospital and community settings in a Brazilian region.

Retrospective analysis of methicillin-resistant staphylococcus aureus skin and soft tissue infection among patients admitted at an academic university hospital from 2011 to 2015: A five-year review

Introduction@#The emergence of methicillin-resistant Staphylococcus aureus (MRSA) is a challenge in the management of skin and soft tissue infections (SSTIs). @*Objective@#To describe the epidemiology of MRSA SSTIs among admitted patients at the University of Santo Tomas Hospital (USTH).@*Methods @#This was a retrospective study of inpatients with MRSA SSTIs from 2011-2015. MRSA infections were classii ed as community-associated (CA-MRSA) and healthcare-associated (HA-MRSA). Demographic characteristics, clinical proi le, comorbidities, complications, risk factors, antibiotic susceptibility and resistance, treatment used, and clinical outcome were determined.@*Results@#Out of the 331 inpatients with Staphylococcus aureus SSTIs, 211 had MRSA with a prevalence of 63.7%, 80.1% of MRSA were CAMRSA while 19.9% were HA-MRSA. The mean age was 41.58 years with male predominance. The majority presented with abscess (62.9%), on the legs (21.8%). The abscess was signii cantly associated with CA-MRSA while infected wounds, previous hospitalization, and surgery were correlated with HA-MRSA. Growing resistance to ciprol oxacin, tetracycline, macrolides, co-trimoxazole, and clindamycin was noted. A low percentage of resistance to vancomycin and linezolid was observed. Almost all cases improved with appropriate antibiotic therapy and 3.3% mortality@*Conclusion@#More than half of the patients with Staphylococcus aureus SSTIs had MRSA. and were mostly CA-MRSA and males. Abscess on the leg was the common presentation and signii cantly associated with CA-MRSA. Infected wounds, previous hospitalization, and surgery were associated with HA-MRSA. There was high resistance of MRSA to ciprol oxacin and tetracycline while low resistance to vancomycin and linezolid. Almost all improved with appropriate treatment.

Phenotypic and Genotypic Characterization, and Detection of PVL Encoding Gene in Methicillin Resistant Staphylococcus Aureus Strains Isolated From Patients Admitted to a Tertiary Hospital In Kuantan, Malaysia

@#Introduction: Methicillin-resistant Staphylococcus aureus is globally a major public health threat. Resistance to methicillin originates from a modified protein (PBP2a) encoded by the mecA gene. The PVL gene as an important virulence factor increases the pathogenicity of MRSA. Epidemiology and characteristics of MRSA differ in different geographical regions. This study was conducted to characterize and determine the antibiotic susceptibility profile of MRSA strains isolated from patients in Hospital Tengku Ampuan Afzan, Pahang, Malaysia and to detect the presence of the mecA and PVL genes in the isolates. Materials and methods: In this study a total of 36 isolates of MRSA have been collected during a period of three months (1stFebruary –30thApril 2018). The susceptibility pattern of the isolates to ten different commonly used antibiotics were determined and the target genes were addressed by real-time PCR experiment. Results: Based on the identifying criteria, 44.4% of the isolates were CA-MRSA, and 55.5% were HA-MRSA. Resistance to oxacillin, cefoxitin and penicillin was 100%, gentamicin 88.8%, erythromycin 33.3%, tetracycline 77.7%, trimethoprim-sulfamethoxazole 61.1%, clindamycin 13.8%, chloramphenicol 11.1%, but no resistant strain of vancomycin was detected. Most of the isolates were resistant to more than three groups of antibiotics. Realtime PCR revealed that all the isolates were mecA positive and 4 isolates were PVL-positive. PVL-positive strains were CA-MRSA and susceptible to clindamycin. Conclusion: The study confirms multi-drug resistant MRSA in the study area, and shows that resistance to methicillin is mecA mediated. PVL carrier strains were present and related to CA-MRSA strains of the isolates.

Is community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) an emerging pathogen among children in Brazil?

ABSTRACT Background: Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is spreading worldwide, but little is known about the epidemiology of this pathogen in Brazil. Objective: To evaluate clinical and microbiological features of children with S. aureus infections admitted to a university hospital. Methods: This was a cross-sectional study evaluating the potential risk factors for CA-MRSA, and a retrospective cohort evaluating in-hospital clinical outcomes. To include patients with both community and hospital-associated infections, we screened the results of the microbiological laboratory tests from January 1, 2012, to December 31, 2016. According to the phenotype, we classified the isolates in Methicillin-Susceptible S. aureus (MSSA), Hospital-Associated Methicillin-Resistant S. aureus (HA-MRSA), and CA-MRSA. Clinical data were collected from the patients' medical records. Results: We identified 279 cases of S. aureus infections (MSSA = 163, CA-MRSA = 69, HA-MRSA = 41). Overall, the incidence density of CA-MRSA and MSSA infections increased while the HA-MRSA incidence density decreased over the study period. CA-MRSA infected patients were more likely to present with skin and soft tissue infections (OR: 2.83, 95%CI: 1.54-5.33, p < 0.001) and osteomyelitis (OR: 4.76; 95%CI: 1.16-22.71, p = 0.014) when compared to MSSA and HA-MRSA infections. Unadjusted case fatality rates were similar between MSSA-infected patients (3.14%, 5/159) and CA-MRSA infected patients (3.80%, 3/79, p = 0.792), while HA-MRSA infected patients were more likely to die in the hospital (12.20%, 5/41, p = 0.013). Conclusions: CA-MRSA is an emergent pediatric pathogen in Brazil. Our results highlight the relevance of choosing an appropriate initial antimicrobial drug for treating children with severe S. aureus infections.

Community-acquired methicillin-resistant Staphylococcus aureus carrying SCCmec type IV and V isolated from healthy children attending public daycares in northeastern Brazil

Abstract Nasal colonization with methicillin-resistant Staphylococcus aureus (MRSA) have increasingly been reported in healthy communities. This study aimed to assess the rate of S. aureus in general and MRSA in particular from nasal secretion of children in daycare centers in Vitória da Conquista, Brazil. The isolates were identified based on morphology, biochemical tests and by PCR. Detection of virulence genes, biofilm production, and susceptibility test by disk diffusion agar were performed. MRSA isolates were characterized by spa, SCCmec, and multilocus sequence typing (MLST). S. aureus were recovered from 70 (47.3%) of 148 children. Among the 11 MRSA strains (15.7%), two SCCmec types (IV and V) were detected. MLST identified four STs related to three clonal complexes (CC): 5, 45, and 398. Four spa types were found circulating in this setting. Resistance of S. aureus isolates to ampicillin, erythromycin, ciprofloxacin, clindamycin, and tetracycline was 80%, 32.8%, 7.1%, 7.1% and 4.3%, respectively. One isolate presented intermediate resistance to vancomycin detected by Etest methodology. All strains were biofilm producers. The virulence genes seb, sec, spa, and pvl were detected in some isolates. This study revealed a high rate of children carrying MRSA among healthy attendees in daycare centers in Vitória da Conquista, Brazil.

Clinical and molecular characteristics of invasive community-acquired methicillin-resistant Staphylococcus aureus infection in Chinese neonates / 中华微生物学和免疫学杂志

Objective To analyze the clinical and molecular features of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infection in neonates and to investigate their antibiotic resistance profiles.Methods A total of 35 invasive CA-MRSA strains were collected from six hospitals in 2014.Multilocus sequence typing (MLST), staphylococcal cassette chromosome mec (SCCmec) typing and spa typing were used to analyze these isolated CA-MRSA strains.In vitro antibiotic susceptibilities of those strains to 15 antibiotics were analyzed by using agar dilution method.Results Up to 88.6% patients were late-onset infection and septicemia (24, 68.5%) was the most common infection among the 35 cases.A total of 16 patients (45.7%) suffered from complications.Caesarean section and premature birth were risk factors for invasive CA-MRSA infection.ST59-MRSA-SCCmecⅣa-t437 (14, 40%) was the most predominant CA-MRSA clone, followed by ST59-MRSA-SCCmecⅤ-t437 (13, 37.1%).The incidence of severe complications caused by ST59-MRSA-SCCmecⅤ-t437 was higher than that caused by ST59-MRSA-SCCmecⅣa-t437 (P<0.05).Up to 85.7% of the isolated CA-MRSA strains were multidrug-resistant strains.Conclusion This study shows that neonatal invasive CA-MRSA infections mainly result in septicemia and are often accompanied by complications and involve multiple organs.Multidrug-resistant CA-MRSA strains are prevalent in neonates.ST59-MRSA-SCCmecⅣa-t437 is the predominant clone causing neonatal invasive CA-MRSA infection.

Characteristics, Detection And Typing Methods Of Community Acquired Methicillin Resistant Staphylococcus Aureus (CA-MRSA) – A Review

@#Staphylococcus aureus aregram positive cocci which colonizethe skin and mucous membranes particularly the anterior nares. Prevalence of nosocomial infections associated with methicillin resistant S. aureus have been reported in hospitals (HA-MRSA) for over five decades. Recently,community-acquired MRSA (CA-MRSA) has emerged as a cause of skin and soft tissue infections in healthy individuals. These strains are sensitive to antimicrobials, carry genes for Panton-Valentine leukocidin (PVL) toxin and belong to the staphylococcal cassette chromosome (SCC) mec type IV or V. The suspected mode of transmission involves close contact with carriers leading to skin or nasal colonization that resultin subsequent active infection. Molecular typing is used to determine the mode of transmission of CA-MRSA in the community.General typing methods such as pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) and specific methods for Staphylococci such as SCCmec typing and spa typing have the capability to characterize bacterial chromosomes and mobile genetic elements. Combination of these molecular typing methods is necessary as each method has its own advantages with respect to discriminatory power, rapidity, cost effectiveness, reproducibility, and ease of performance.

Community-associated methicillin-resistant Staphylococcus aureus infections in Aboriginal children attending hospital emergency departments in a regional area of New South Wales, Australia: a seven-year descriptive study

Objective: Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) can cause bacterial skin infections that are common problems for Aboriginal children in New South Wales (NSW). MRSA is not notifiable in NSW and surveillance data describing incidence and prevalence are not routinely collected. The study aims to describe the epidemiology of CA-MRSA in Aboriginal children in the Hunter New England Local Health District (HNELHD). Methods: We linked data from Pathology North Laboratory Management System (AUSLAB) and the HNELHD patient administration system from 33 hospital emergency departments. Data from 2008–2014 for CA-MRSA isolates were extracted. Demographic characteristics included age, gender, Aboriginality, rurality and seasonality. Results: Of the 1222 individuals in this study, 408 (33.4%) were Aboriginal people. Aboriginal people were younger with 45.8% aged less than 10 years compared to 25.9% of non-Aboriginal people. Most isolates came from Aboriginal people who attended the regional Tamworth Hospital (193/511 isolates from 149 people). A larger proportion of Aboriginal people, compared to non-Aboriginal people, resided in outer regional (64.9% vs 37.2%) or remote/very remote areas (2.5% vs 0.5%). Most infections occurred in summer and early autumn. For Aboriginal patients, there was a downward trend through autumn, continuing through winter and spring. Discussion: Aboriginal people at HNELHD emergency departments appear to represent a greater proportion of people with skin infections with CA-MRSA than non-Aboriginal people. CA-MRSA is not notifiable in NSW; however, pathology and hospital data are available and can provide valuable indicative data to health districts for planning and policy development.

Infecciones por Staphylococcus aureus resistente a la meticilina adquirido en la comunidad en pacientes de Villavicencio, Colombia / Community-acquired methicillin resistant Staphylococcus aureus infections in Villavicencio, Colombia

Introducción: los Staphylococcus aureus son patógenos muy versátiles, con capacidad de causar un gran rango de enfermedades en los humanos. Sin embargo, el papel que juegan sus factores de virulencia en el desarrollo de las infecciones no se ha entendido completamente. Algunos tipos clonales están muy bien equipados para causar enfermedad en todas las personas, mientras que otros causan enfermedad solo a algunos miembros de una comunidad. Objetivo: determinar la prevalencia de infecciones por Staphylococcus aureus resistente a meticilina adquiridas en la comunidad en pacientes de la ciudad de Villavicencio, Colombia. Métodos: estudio descriptivo, prospectivo de corte transversal, en 46 muestras obtenidas de absceso, secreción, sangre, orina, líquido pericárdico, líquido pleural, aspirado traqueal, forúnculo. Los individuos participantes no estuvieron hospitalizados en los últimos meses, ni recibieron tratamiento antimicrobiano y no presentaron signos y/o síntomas clínicos. Los aislamientos fueron identificados por pruebas convencionales microbiológicas y se determinó la susceptibilidad antimicrobiana para los diferentes antibióticos a través de MicroScan™ Pos Combo Panel Type pc 24 (Dade Behring, USA). Se detectaron los genes nuc, mecA y LukS-PV relacionados con la identificación y virulencia de esta especie. Resultados: de las 46 muestras analizadas, el 100 por ciento resultaron positivas para S. aureus, de éstas 46 (100 %) fueron resistentes a meticilina y 44 (95,6 por ciento) presentaron el gen para la LPV. Conclusiones: en Colombia y específicamente en Villavicencio poco se conoce de la epidemiologia del SARM- AC. Deben realizarse estudios de vigilancia epidemiológica y tipificación molecular que nos acerquen a entender más el comportamiento de su epidemiologia y así mismo diseñar mejores estrategias de prevención y control(AU)

Introduction: staphylococcus aureus is a very versatile pathogen, with a capacity to cause a great range of conditions in humans. However, the role played by its virulence factors in the development of infection is not thoroughly understood. Some clonal types are very well equipped to cause disease in all persons, whereas others only affect some members of a community. Objective: determine the prevalence of community-acquired methicillin resistant Staphylococcus aureus infections in patients from the city of Villavicencio in Colombia. Methods: a descriptive cross-sectional prospective study was conducted of 46 samples obtained from abscesses, secretions, blood, urine, pericardial fluid, pleural fluid, tracheal aspirates and boils. Participants had not been hospitalized in recent months nor had they received any antimicrobial treatment, and they did not present any clinical signs and/or symptoms. The isolates were identified by means of conventional microbiological tests. Antimicrobial susceptibility to the various antibiotics was determined using MicroScan™ Pos Combo Panel Type pc 24 (Dade Behring, USA). The genes nuc, mecA and LukS-PV were detected. These are related to the identification and virulence of the study species. Results: of the 46 samples analyzed, 46 (100 percent) were positive for S. aureus, 46 (100 percent) were resistant to methicillin and 44 (95.6 percent) contained the LPV gene. Conclusions: in Colombia and specifically in Villavicencio, little is known about the epidemiology of CA-MRSA. Epidemiological screening and molecular typing studies should be conducted to gain insight into the epidemiology of CA-MRSA and design better prevention and control strategies(AU)

Antimicrobial Resistance and Molecular Characteristics of Nasal Staphylococcus aureus Isolates From Newly Admitted Inpatients

Staphylococcus aureus, or methicillin-resistant S. aureus (MRSA), is a significant pathogen in both nosocomial and community infections. Community-associated MRSA (CA-MRSA) strains tend to be multi-drug resistant and to invade hospital settings. This study aimed to assess the antimicrobial resistance and molecular characteristicsof nasal S. aureus among newlyadmitted inpatients.In the present study, 66 S. aureus isolates, including 10 healthcare-associated MRSA (HA-MRSA), 8 CA-MRSA, and 48 methicillin-sensitive S. aureus (MSSA) strains, were found in the nasal cavities of 62 patients by screening 292 newlyadmitted patients. Antimicrobial resistance and molecular characteristics of these isolates, including spa-type, sequence type (ST) and SCCmec type, were investigated. All isolates were sensitive to linezolid, teicoplanin, and quinupristin/dalfopristin, but high levels of resistance to penicillin and erythromycin were detected. According to D-test and erm gene detection results, the cMLSB and iMLSB phenotypes were detected in 24 and 16 isolates, respectively. All 10 HA-MRSA strains displayed the cMLSB phenotypemediated by ermA or ermA/ermC, while the cMLSB CA-MRSA and MSSA strains carried the ermB gene. Molecular characterization revealedall 10 HA-MRSA strains were derived from the ST239-SCCmec III clone, and four out of eight CA-MRSA strains were t437-ST59-SCCmec V. The results suggest that patients play an indispensable role in transmitting epidemic CA-MRSA and HA-MRSA strains.

Profile of community-acquired Methicill in Resistant Staphylococcus Aureus Skin and Soft-Tissue infections among children admitted at the Philipine General Hospital

Abstract@#CA-MRSA infection is a global concern. It is important to determine the local prevalence of CA-MRSA skin and soft-tissue infection as this information will provide a more accurate and rational basis for empiric treatment, improve management and outcomes in patients, and reduce the economic burden associated with failed treatment. This study was conducted to determine the clinical profile and prevalence of CA-MRSA skin and soft tissue infections among pediatric patients admitted at the Philippine General Hospital. @*Methods@#A prospective, observational study was performed involving all pediatric patients admitted at U-PGH for skin and soft tissue infections from September to December 2012. Demographic profile, clinical characteristics of patients, results of laboratory examinations, the outcome of treatment were described and summarized. Risk factors for acquisition of MRSA were also determined. Period-prevalence was computed. @*Results@#There were 25 children admitted for SSTIs, 16 have positive cultures and 62.5% of these had CA-MRSA. The majority were male children younger than 5 years old without identifiable risk factors. infections presented as solitary masses and cellulitis usually at the head and neck area. isolates were taken from aspirates during incision and drainage. Invasive infections were seen 3 patients. The length of hospital stay, type of antibiotics used and surgery performed was variable. All patients were discharge well and there were no mortalities. The period prevalence of CA-MRSA among children with SSTI was 0.36. @*Conclusion@#CA-MRSA as a cause of SSTIs in Filipino children is an emerging concern, especially in very young patients even without risk factors. management of SSTI’s should include incision and drainage of abcesses and prompt submission of aspirates for culture and antibiotic sensitivity testing. The period prevalence of pediatric patients with SSTI is high among hospitalized patients. Empiric antibiotics with MRSA coverage such as clindamycin and vancomycin should be considered clinical situations wherein MRSA is deemed likely.

Molecular characterization of community- & hospital-acquired methicillin-resistant & methicillin-sensitive Staphylococcus aureus isolates in Sikkim.

Background & objectives: The two major genotypic markers that distinguish community acquired (CA) from hospital acquired (HA) methicillin resistant staphylococcus aureus (MRSA) isolates are the architecture of mobile genetic element (SCCmec type) and presence of panton valentine leukocidin (PVL) toxin. This study was conducted to determine the molecular characteristics of CA- and HA- MRSA and methicillin sensitive S. aureus (MSSA) isolates in Sikkim. Methods: A total of 150 clinical isolates of S. aureus isolated from various clinical specimens were subjected to duplex (mec-A and pvl gene) and multiplex (SCCmec typing) PCR. Results: of the 150 isolates, 53 (35.33%) and 66 (44%) were positive for mec-A (MRSA) and pvl genes, respectively. Thirty eight (25.33%) met the definition of CA-MRSA and 15 (10%) of HA-MRSA and the remaining 63 (42%) and 34 (22.66%) as CA- and HA-MSSA, respectively. No significant difference was seen in the distribution of PVL toxin in MRSA and MSSA isolates, but it was significantly (P<0.001) high in overall MRSA isolates than in MSSA. The majority of the MRSA isolates showed a double amplification band of SCCmec type III plus V (54.71%), and only a fewer isolates were amplified by single DNA fragments of type I (1.88%), III (3.77%), IVa (1.88%) and V (11.32%). SCCmec types I, III, IVa, were found only in HA-MRSA isolates, whereas type V in both the CA- and HA-MRSA. AST pattern showed that 18.42 per cent (7/38) and 46.66 per cent (7/15) were multidrug resistant (MDR)-CA-MRSA and MDR-HA-MRSA, respectively. Interpretation & conclusions: The present results show that SCCmec type V MRSA has been on the rise, and genotypic markers such as pvl gene detection used for the differentiation of these clinically distinct isolates of MRSA may not be reliable.

Electric stimulations mediated beta lactam resistance reversal and correlation with growth dynamics of community acquired methicillin resistant Staphylococcus aureus.

The community associated methicillin resistant Staphylococcus aureus (CA-MRSA) is a serious issue of public health. Here, we conducted an experimental approach to determine: (i) the optimal significant stimulation range of electrical current for effective checking of CA-MRSA growth; (ii) the effect of electrical stimulations on methicillin susceptibility and possible beta lactam resistance reversal; and (iii) the variation in the level of ATP as function of exposure to electric current. An 8 chambered electrical system was developed for DC flow in control and test sets, with and without drug (oxacillin 4 mg/ml). Measurement of growth by CFU/ml and spectrometry, susceptibility and ATP levels were calculated and interpreted. Linear pattern in reduction of ATP was observed with respect to the intensity of electric current (EC) and an enhanced inhibitory effect was explicit with 1000 microampere (μA) with 30 min exposure. At 4000 μA exposure to DC at 180 min and in combination of drug (μA+D), the growth of CA-MRSA was substantially checked to 0.23 absorbance in comparison to current without drug and the effect of DC electrical current to the culture showed that 10 μA, 100 μA and 4000 μA current exposure in combination of oxacillin (μA+D), markedly reduced the CFU to an average of 256.4. ATP level was linearly reduced with exposure to EC.

Staphylococcus aureus nasal carriage among outpatients attending primary health care centers: a comparative study of two cities in Saudi Arabia and Egypt

Epidemiological and molecular data on community acquired methicillin resistant Staphylococcus aureus (CA-MRSA) are still scarce in both Egypt and Saudi Arabia. There is almost no data regarding methicillin resistant Staphylococcus aureus (MRSA) prevalence in both countries. This study was conducted to investigate the prevalence and molecular epidemiology of S. aureus and MRSA nasal carriage among outpatients attending primary health care centers in two big cities in both countries. A total of 206 nasal swabs were obtained, 103 swabs from each country. S. aureus isolates were characterized by antibiotic susceptibility, presence of mecA and PVL genes, SCCmec-typing and spa typing, the corresponding Multi locus sequence typing clonal complex was assigned for each spa type based on Ridom StaphType database. MRSA was detected in 32% of the Egyptian outpatients while it was found in 25% of the Saudi Arabian outpatients. All MRSA isolates belonged to SCCmec type V and IVa, where some isolates in Saudi Arabia remained nontypeable. Surprisingly PVL+ isolates were low in frequency: 15% of MRSA Egyptian isolates and 12% of MRSA isolates in Saudi Arabia. Two novel spa types were detected t11839 in Egypt, and t11841 in Saudi Arabia. We found 8 spa types among 20 isolates from Egypt, and 12 spa types out of 15 isolates from Saudi Arabia. Only two spa types t008 and t223 coexisted in both countries. Four clonal complexes (CC5, CC8, CC22, and CC80) were identified in both Egypt and Saudi Arabia. However, the data collected lacked a representation of isolates from different parts of each country as only one health center from each country was included, it still partially illustrates the CA-MRSA situation in both countries. In conclusion a set of control measures is required to prevent further increase in MRSA prevalence.

Portación nasal de staphylococcus aureus meticilino resistentes en poblaciones de la comunidad / Nasal colonization with methicillin-resistant staphylococcus aureus in the community

Staphylococcus aureus (SA) causa infecciones graves. Las debidas a cepas resistentes a meticilina representan undesafío terapéutico. Actualmente hay un aumento de casos de infecciones de piel y tejidos blandos con inusitadagravedad debidas a S. aureus meticilinorresistentes adquiridos en la comunidad (SAMR AC) pero se desconoce latasa de colonización de la población sana en nuestro medio. El propósito de este trabajo fue determinar la portación nasal en grupos de deportistas y personas que habitan en residencias de ancianos. Se tomaron hisopados nasales de 332 personas, 180 alojados en 4 residencias de ancianos y 152 de 7 grupos de deportistas, los cuales fueron extraídos, conservados y cultivados por los métodos convencionales. La caracterización molecular fue efectuada por PCR buscando el tipo de cassette cromosómico estafilocócico con el gen mecA (SCCmecA) y el gen que codifica la leucocidina de Panton-Valentine. Se asiló SA en 83 pacientes (25%), de los cuales 40 fueron SA meticilinosensibles (21,1%) y 13 SAMR (3,9%). Ocho casos fueron clasificados fenotípicamente y genotípicamente como SAMR AC (2,4%). Todos tenían SCCmecA tipo IV. Es necesaria una atenta vigilancia ya que las infecciones de piel y tejidos blandos de la comunidad no deberían ser tratadas con antibióticos betalactámicos

Staphylococcus aureus isolates are common causes of skin and soft tissue infections and other invasive infections. Those due to methicillin resistant strains represent a therapeutic challenge. Currently there is an increase in cases due to community-acquired methicillin-resistant S. aureus (CA-MRSA) but the rate of colonization of the healthy population is unknown in our country. The purpose of this study was to determine nasal carriage in sportsmen and people living in nursing homes in Rosario. Nasal swabs of 101 people staying in 4 nursing homes and of 98 from 7 groups of athletes were obtained. The samples were extracted, preserved, and cultured by conventional methods. PCR was performed in order to study the type of staphylococcal chromosome cassette mecA (SCCmecA) gene and the gene encoding the Panton-Valentine leukocidin. S. aureus was isolated in 48 patients (24.1%), of which 40 were methicillin-sensitive S. Aureus (20.1 %), and 8 methicillin resistant S. aureus (4.0%). Five cases were characterized phenotypically and genotypically as CA-MRSA (2.5%). All of them had type IV SCCmecA. Careful surveillance is required because skin and soft tissue infections in the community should not be treated with beta-lactam antibiotics

Clinical and Diagnostic Significance of Methicillin-resistant Staphylococcus aureus Infection in Bangladesh: A Systematic Review.

Background: Accurate diagnosis of Methicillin-resistant Staphylococcus aureus (MRSA) is essential for the clinician. In Bangladesh MRSA creates a great problem for the treatment of infection. Objective: The purpose of the present study was to observe the clinical and diagnostic significance of MRSA infection in Bangladesh. Design: Systematic review of published articles in Bangladesh. Data Sources: PubMed (Medline), Embase, Scopus, Web of Science, the Cochrane Library, and the World Health Organization (WHO) Regional Databases (African, eastern Mediterranean, Latin American and Caribbean, western Pacific, and southeast Asian regions) as well as Google Scholar, Banglajol, Asiajol. Review Methods: The search was restricted to full articles published from January 2000 (publication date of the first study identified by the research) to December 2013. Studies were excluded that did not provide appropriate data on the prevalence of MRSA. Only English language was applied. Result: A total number of 125 studies were identified during systematic review which were relevant to the present research question and among these only 14 studies were met the criteria for analysis. The level of evidence and freedom from bias of these studies were generally low. MRSA was diagnosed phenotypic in most of the articles. Majority were isolated from skin wound. The isolation rate of MRSA among all culture isolates ranged from 4.8-78.7%. From all studies diagnosis of MRSA infection was done from hospital setting; however, only two studies had been reported from community settings though the CDC definition was not followed in either study. Conclusion: Significance of methicillin-resistant Staphylococcus aureus infection in Bangladesh is very high leading to a huge clinical as well as laboratory burden in the heath care facilities as well as in the community settings of Bangladesh.

The multifaceted resources and microevolution of the successful human and animal pathogen methicillin-resistant Staphylococcus aureus

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most important bacterial pathogens based on its incidence and the severity of its associated infections. In addition, severe MRSA infections can occur in hospitalised patients or healthy individuals from the community. Studies have shown the infiltration of MRSA isolates of community origin into hospitals and variants of hospital-associated MRSA have caused infections in the community. These rapid epidemiological changes represent a challenge for the molecular characterisation of such bacteria as a hospital or community-acquired pathogen. To efficiently control the spread of MRSA, it is important to promptly detect the mecA gene, which is the determinant of methicillin resistance, using a polymerase chain reaction-based test or other rapidly and accurate methods that detect the mecA product penicillin-binding protein (PBP)2a or PBP2’. The recent emergence of MRSA isolates that harbour a mecA allotype, i.e., the mecC gene, infecting animals and humans has raised an additional and significant issue regarding MRSA laboratory detection. Antimicrobial drugs for MRSA therapy are becoming depleted and vancomycin is still the main choice in many cases. In this review, we present an overview of MRSA infections in community and healthcare settings with focus on recent changes in the global epidemiology, with special reference to the MRSA picture in Brazil.

Staphylococcus aureus meticilino resistente adquirido en la comunidad: una nueva amenaza / Community acquired methicillin-resistant Staphylococcus: A new threat

Objetivos: Conocer la frecuencia de Staphylococcus aureus meticilino resistente adquirido en la comunidad (SAMR-AC) en neumonía adquirida en la comunidad (NAC); examinar sus características clínicas - evolutivas y analizar factores de riesgo. Pacientes, material y métodos: Estudio retrospectivo, descriptivo, observacional, realizado en una unidad de cuidados intensivos respiratorios entre 2006 y 2012. Resultados: Se evaluaron 180 pacientes con NAC con diagnóstico etiológico. Etiologías más frecuentes: Streptococcus pneumoniae (50.5%), Haemophillus influenzae (18.3%) ySAMR-AC (12.2%, 22 casos). La neumonía por SAMR-AC se presentó en individuos jóvenes, mayoritariamente hombres. En el 81.8% de los casos el foco primario fue infección de piel y estructuras relacionadas (IPER), 95.4% presentó criterios clínicos de sepsis, 72.7% tuvo compromiso radiológico bilateral y 45.5% desarrolló derrame pleural. El 40.9% requirió ventilación mecánica y el 45.4% utilizó drogas vasoactivas. El 81.8% de los pacientes no alcanzó criterios de estabilidad clínica al cabo de la primer semana y la mortalidad fue del 36.3%, significativamente superior al resto de los microorganismos (8.8%, p<0,001). Los factores clínicos asociados con mayor riesgo de SAMR-AC fueron la presencia de IPER concomitante, compromiso radiológico bilateral, presencia de criterios clínicos de sepsis, edad inferior a 30 años y requerimiento de drogas vasoactivas. Los factores que se asociaron con mortalidad en NAC fueron la etiología por SAMR-AC y el compromiso radiológico bilateral. Conclusiones: La neumonía por SAMR-AC es una patología emergente, asociada a elevada morbimortalidad. Debe ser considerada en pacientes jóvenes, con presencia concomitante de IPER, compromiso radiológico bilateral, criterios clínicos de sepsis o necesidad de drogas vasoactivas.

Objectives: To know the incidence of Community Acquired Pneumonia (CAP) caused by Methicillin Resistant Sthaphylococcus aureus (MRSA), to examine their clinical and developmental characteristics and to analyze risk factors. Materials and Methods: Retrospective, descriptive and observational study carried out at a Respiratory Intensive Care Unit, between 2006 and 2012. Results: 180 patients with etiologic diagnosis of CAP were evaluated. The most common causes were Streptococcus pneumoniae (50.5%), Haemophillus influenzae (18.3%) and MRSA (12.2%, 22 cases). Community Acquired MRSA (CA-MRSA) pneumonia was present in young people, especially in male. In 81.8% of the cases, skin and related structure infections (SRSI) were the primary focus, 95.4% presented clinical criteria of sepsis, 72.7% had bilateral radiology involvement and 45.5% developed pleural effusion. 40.9% needed mechanical ventilation and 45.4% used vasoactive drugs. Clinical stability at the first week was not reached in 81.8% and mortality rate was 36.6%, significantly higher than for pneumonia caused by other microorganisms (8.8% p<0,001). Clinical factors related with high risk of CA-MRSA pneumonia were the concomitant presence of SRSI, bilateral radiology involvement, clinical criteria of sepsis, age <30 years old and need for vasoactive drugs. Factors related to CAP mortality were CA-MRSA aetiology and bilateral radiology involvement. Conclusions: CA-MRSA pneumonia is an emergent disease with high morbidity and mortality. It must be considered in young patients, with SRSI, bilateral radiology involvement, clinical criteria of sepsis or intake of vasoactive drugs.

Incidence of Community-associated Methicillin-resistant Staphylococcus aureus Infections in a Regional Hospital / Journal of Rural Medicine

<b>Background and Objective:</b> Since the early 2000s, the incidence of methicillin-resistant <i>Staphylococcus aureus</i> (MRSA) infections among the community of people lacking known healthcare risk factors has increased. This MRSA infection is referred to as community-associated MRSA (CA-MRSA) infection and is distinct from hospital-associated MRSA (HA-MRSA) infection, which occurs among people with known healthcare risk factors. Understanding the epidemiology of CA-MRSA infections is critical; however, this has not been investigated in detail in Japan. Our objective was to investigate the incidence of CA-MRSA infections in a regional hospital. <BR><b>Patients and Methods:</b> We investigated CA-MRSA isolates and infections in a rural regional hospital by reviewing medical records of one year. Infections were classified as CA-MRSA if no established risk factors were identified. <BR><b>Results:</b> During 2008, 31 <i>Staphylococcus aureus</i> (<i>S. aureus</i>) isolates were detected in 29 unique patients, with 1 methicillin-sensitive <i>S. aureus</i> (MSSA) isolates obtained from 19 patients (66%) and MRSA obtained from 10 patients (34%). In the 10 patients with MRSA, the number of HA-MRSA and CA-MRSA cases were nine (32% of patients with <i>S. aureus</i> isolates) and one (3%), respectively. The patient with CA-MRSA was diagnosed with cellulitis due to CA-MRSA. All nine patients with HA-MRSA exhibited colonization. <BR><b>Conclusion:</b> We observed a CA-MRSA case in a regional hospital in Japan, suggesting that incidence trends of CA-MRSA should be considered in future research and treatment.