Emergence and spread of a new community-genotype methicillin-resistant Staphylococcus aureus clone in Colombia

Treating osteoarticular infections in a Role 2 in Chad: a bacterial epidemiological study

INTRODUCTION

The treatment of osteoarticular infections in Africa is a medical and surgical challenge due to the difficulties in managing antibiotic therapy after the surgical procedure. The objectives of this study were to identify the types of bacteria in osteoarticular lesions in patients treated in Chad and to determine the spectrum of resistance encountered and the efficacy of available antibiotics.

MATERIAL AND METHODS

This is a retrospective study of all intraoperative osteoarticular and soft tissue samples taken in a French Role 2 Medical Treatment Facility of N'Djamena during surgery for chronic osteoarticular infections, in Chad, for 1 year.

RESULTS

A total of 160 bacterial strains were identified, with a predominance of Gram-negative bacillus (GNB) and staphylococcus infections. Among staphylococci, 80% were methicillin-sensitive streptococci which were generally multidrug-sensitive. Enterococci were resistant to third-generation cephalosporins, first-generation fluoroquinolones and gentamycin. Among GNB, there was a predominance of enterobacteria compared with non-fermenting GNB, of which 52% were multidrug-resistant and produced extended spectrum beta-lactamases (ESBL).

CONCLUSION

Staphylococcus aureus infections are most often sensitive to available antibiotics and therefore have better prognoses than infections caused by other bacteria. In contrast, in half of the cases of GNB, infections were caused by bacteria producing ESBL, thus posing the problem of multidrug-resistance, the risks of which are increased in precarious situations. Therefore, the type of bacteria appears to be a major prognostic factor in the treatment of osteoarticular infections in a Role 2 in Chad. This criterion will need to be considered before any treatment decisions are made.

Clonal Distribution and Antibiotic Susceptibility of Staphylococcus aureus from Pediatric Patients: 8-Year Trends in a Children's Hospital in Colombia

Emergence of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) strains in healthcare settings has changed the hospital epidemiology of MRSA in the last few years. Despite a global increase in MRSA frequency, infections caused by methicillin-susceptible S. aureus (MSSA) have persisted in healthcare settings and the community. Staphylococcus aureus isolates were collected between 2009 and 2017 at the Children's Hospital of a Caribbean city in South America. Methicillin-resistant isolates were subjected to SCCmec typing. Representative isolates were analyzed by multilocus sequence typing (MLST) and spa typing. Antibiotic susceptibility was assessed by agar dilution method. D-zone test was performed in erythromycin-resistant isolates to determine macrolide/lincosamide/streptogramin resistance. Spa typing revealed 10 different spa types. The main epidemic clones circulating during the study period were: ST8-MRSA-IVc, ST923-MRSA-IVa and ST8-MRSA-IVa. The study found high frequencies of PVL genes and resistance to erythromycin and clindamycin in the isolates. This study provides the first description of the population structure of MRSA and MSSA causing infections attended in the participating Children's Hospital. ST8-MRSA-IVc, ST923-MRSA-IVa and ST8-MRSA-IVa were the most prevalent in the isolate population.

Epidemiology of the Staphylococcus aureus CA-MRSA USA300 in Belgium

The methicillin-resistant Staphylococcus aureus (MRSA) sequence type (ST) 8 Panton-Valentine toxin (PVL)-positive USA300 clone has a worldwide distribution. The USA300 North American (NA) variant, harbouring the arginine catabolic mobile element (ACME), is predominant in the USA while the Latin American (LV) variant is predominant in Northern South America. Both variants have failed to become endemic in Europe. We examined here the epidemiology of the USA300 clone in Belgium from 2006 to 2019. A total of 399 clonal complex 8 PVL-positive MRSA isolates received between 2006 and 2019 by the Belgian National Reference Laboratory for S. aureus were investigated for the presence of ACME. Selected ACME-positive (n=102) and ACME-negative (n=16) isolates were sequenced, characterized for the presence of several resistance and virulence molecular markers and subjected to phylogenetic analysis. A total of 300 isolates were USA300-NA (ACME-positive), while only 99 were ACME-negative. Most USA300-NA interspersed in the phylogeny analysis with isolates from other countries, suggesting multiple introductions. However, two big clades were maintained and spread over a decade, peaking between 2010 and 2017 to finally decrease. Few ACME-negative isolates, mainly related to trips to South America, were identified as USA300-LV. The remaining ACME-negative isolates were ST8 SCCmec IVb or ST923 SCCmec IVa (COL923). Two clades of the USA300-NA clone have successfully spread in Belgium, but seem to currently decrease. Related South American variants have been detected for the first time in Belgium, including the emerging COL923 clone.

Guía de práctica clínica para el diagnóstico y manejo de las infecciones de piel y tejidos blandos en Colombia

Las infecciones de piel y tejidos blandos (IPTB) representan la tercera causa de consulta por enfermedad infecciosas a los servicios médicos, después de las infecciones respiratorias y urinarias. Se presenta una guía de práctica clínica (GPC) con 38 recomendaciones basadas en la evidencia, graduadas bajo el sistema SIGN, para el diagnóstico y tratamiento de pacientes adultos con IPTB en el contexto colombiano, posterior a un proceso de adaptación de GPC publicadas y la búsqueda sistemática y síntesis de literatura para la actualización de la evidencia científica. Además, se realizó un consenso de expertos para la evaluación de las potenciales barreras para la implementación de las recomendaciones y la evaluación del grado de recomendación en el contexto local.

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

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.

Molecular epidemiology of the community-associated methicillin-resistant staphylococcus aureus clones: a synthetic review

The article presents a synthetic molecular characterization of the methicillin-resistant Staphylococcus aureus and describes the most important community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) clones that circulate nowadays in the world: the main molecular and epidemiological characteristics, as well as notions related to the clinic of infections produced by these clones and their antibiotic resistance spectrum.

The predominant clone of CA-MRSA in North America is USA300 – ST8-IV in North America, in Australia – Queensland (Qld) MRSA (ST93-IV), in Europe – ST80-IV, in Asia there is a high heterogeneity of clones population, in Africa the distribution of CA-MRSA clones is unclear, and in South America – USA 1100 and USA300-Latin American variant are predominant.

The molecular diagnosis is performed by highly specialized institutions. The knowledge of clones allows the study of antibiotic resistance spectrum for each one, a fact of great importance for medical practice. Molecular epidemiology of the CA-MRSA shows that lowly restricted sales of antibiotics in shops and pharmacies, as well as medical prescribing practices without a laboratory investigation, especially in Eastern Europe and Asia, contribute to the development of new MRSA clones with increased resistance to antibiotics.