Resistência à mupirocina entre isolados de Staphylococcus aureus de profissionais de enfermagem

Susceptibility to chlorhexidine and mupirocin among methicillin-resistant Staphylococcus aureus clinical isolates from a teaching hospital

Despite the widespread use of chlorhexidine (CHX) to prevent infection, data regarding the in vitro action of CHX against methicillin-resistant Staphylococcus aureus(MRSA) are limited. Clinical isolates from Hospital das Clinicas, Sao Paulo, Brazil, identified during 2002/2003 and 2012/2013 were studied to describe the susceptibility to CHX and mupirocin, molecular characteristics, and virulence profile of MRSA. Susceptibility test to Mupirocin was performed by the disk diffusion method and to CHX by the agar dilution technique. PCR for virulence genes, mecA gene and Staphylococcal Cassette Chromosome mec (SCCmec) types were investigated as well. Mupirocin- and CHX-resistant isolates were sequenced using the Illumina^TM plataform. Two hundred and sixteen MRSA clinical isolates were evaluated: 154 from infected and 62 from colonized patients. Resistance to mupirocin was observed in four isolates assigned as SCCmec type III and STs (ST05; ST239 and ST105) carrying mupA and blaZ, two of them co-harboring the ileS gene. Only one isolate assigned as SCCmec type III was resistant to CHX (MIC of 8.0 μg.mL^-1) and harbored the qacA gene. Resistance to chlorhexidine and mupirocin were found in isolates carrying qacA and mupA in our hospital. Since these genes are plasmid-mediated, this finding draws attention to the potential spread of resistance to mupirocin in our hospital.

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.

Colonização bacteriana e resistência antimicrobiana em trabalhadores de saúde: revisão integrativa

Resumo Objetivo: Analisar as evidências científicas disponíveis na literatura sobre os microrganismos que colonizam os trabalhadores de saúde e sua associação com a resistência a antimicrobianos. Métodos: Revisão integrativa de literatura. A busca dos estudos primários foi realizada nas bases de informação: National Library of Medicine National Institutes of Health, Cumulative Index to Nursing and Allied Health Literature, Web of Science, Scopus e Biblioteca virtual em saúde. Os descritores utilizados foram aplicados de acordo com particularidades de cada base de dados e obtidos por consulta nos Descritores de Ciências em Saúde e Medical Subject Headings. Resultados: A revisão foi composta de 14 estudos primários. Na análise das amostras as pesquisas encontraram principalmente Staphylococcus aureus e Staphylococcus aureus resistente a meticilina colonizando os trabalhadores de saúde. A resistência das bactérias à clindamicina e oxacilina apresentaram maior destaque nas amostras. Conclusão: O Staphylococcus aureus foi evidenciado nos estudos como principal bactéria colonizadora dos trabalhadores de saúde. A preocupação é que essas bactérias apresentam grande capacidade de resistência aos antibióticos beta-lactâmicos.

STAPHYLOCOCCUS AUREUS IN NURSING PROFESSIONALS AND THE MICROORGANISM’S SUSCEPTIBILITY PROFILE TO ANTIMICROBIALS

ABSTRACT Objective: to identify the carrier’s state and the susceptibility profile of Staphylococcus aureus isolated from saliva and nasal secretion of nursing professionals to antibiotics. Method: cross-sectional study that used saliva and nasal secretion samples of 100 nursing professionals who provide care for patients with HIV/Aids. Results: forty-three percent of the participants presented positive saliva or nasal secretion samples for Staphylococcus aureus. Of the 74 nasal secretion samples with Staphylococcus aureus, 14.9% presented oxacillin resistance; 91.9% presented penicillin resistance; 44.6% presented erythromycin resistance, and 41.9% presented clindamycin resistance. Of the 12 positive saliva samples, 16.7% presented oxacillin resistance; 100.0% presented penicillin resistance; 33.4% presented erythromycin resistance, and 25.0% presented clindamycin resistance. Conclusion: nursing professionals, once aware of their carrier state of multi-resistant microorganisms, will supervise their care practices and more efficiently adopt measures for prevention and control of the epidemiological chain of these bacteria in their work environment.