Marcadores fenotípicos e genotípicos de resistência aos antimicrobianos em enterobactérias e Staphylococcus spp. e detecção de genes para a produção de enterotoxina estafilocócica em cepas isoladas de equipamentos da cozinha de um hospital universitário no município do Rio de Janeiro

• Autor(a) principal: Miyahira, Roberta Fontanive
• Data de Publicação: 2012
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UERJ
• Texto Completo: http://www.bdtd.uerj.br/handle/1/14365
• topic: Salmonella spp; Enterobacteria; Staphylococcus spp; Kitchen equipment; Antimicrobial resistance; Beta-lactamases; Enterotoxins; Salmonella spp; Enterobacterias; Staphylococcus spp; Equipamentos de cozinha hospitalar; Resistência aos antimicrobianos; β-lactamases; Enterotoxinas; Salmonella; Staphylococcus; Enterobacterias; Infecção hospitalar; Resistência beta-lactâmica; Equipamentos hospitalares; CNPQ::CIENCIAS BIOLOGICAS::MICROBIOLOGIA

Enterobacteria are important agents of infections related to health care services and antimicrobial resistance by production of β-lactamases is an additional problem in this scenario. Staphylococcus spp is considered a human pathogen frequently associated with infections acquired in hospital. The aim of this study was to evaluate antimicrobial resistance in isolates of enterobacteria and Staphylococcus spp. isolated from equipment used in the preparation of diets for the patients admitted to a university hospital in the city of Rio de Janeiro, and to verify presence of genes encoding enterotoxins in Staphylococcus spp. Enterobacteria and Staphylococcus spp. were isolated and identified by conventional methodology. All isolates were tested by disk diffusion method. We performed the minimum inhibitory concentration (MIC) by broth microdilution technique. The search for genes encoding β-lactamases in enterobacteria was performed by polymerase chain reaction (PCR) for the genes blaTEM, blaSHV, blaCTX-M, blaOXA-1 and blaCMY-2. For Staphylococcus spp. were screened by PCR, the genes for resistance to methicillin, gentamicin and erythromycin and the genes encoding enterotoxins (sea-see, seg-sej, sen-ser and seu). We recovered 97 isolates of enterobacteria, 40 from blender and 57 from mixer and 40 isolates of Staphylococcus spp., 20 of each equipment. Among the enterobacteria, Enterobacter spp. was isolated more frequently (n=37, 38%). We also isolated six isolates of Salmonella spp. Among the enterobacteria, 80% (n=79) were resistant to at least one antimicrobial and 38% (n=37) to three or more. Phenotypic expression of presumptive β-lactamase type AmpC was detected in 32 strains. The blaCMY-2 gene was not found. Twelve isolates showed inhibition zones with screaning test positive for the detection of ESBL. We have detected the presence of the gene blaSHV in K. pneumoniae subsp. pneumoniae. The sequencing of the gene identify as blaSHV-36. Among the Staphylococcus, eight were identified as coagulase-positive (SCP) and 32 as coagulase-negative (SCN). The eight isolates of SCP were identified as S. aureus subsp. aureus. Among the SCN, the most frequently identified species were: S. caprae (n=7, 17.5%), S. simulans (n=5, 12.5%) and S. epidermidis (n=4, 10%). Of these, 83% (n=33) were resistant to at least one antimicrobial and 30% (n=12) were resistant to more than three. Two isolates (5%) of S. epidermidis showed resistance to six antibiotics and genes for resistance to methicillin, erythromycin and gentamycin. All isolates that were resistant to gentamicin in MIC and TSA showed the gene aac(2')/aph(6''). ermB gene was also observed in S hominis subsp hominis that was resistance to erythromycin in MIC and TSA. We have detected the presence of at least one gene encoding enteroxotxina in 83% (n=33) of isolates. The gene seg was detected in 11 isolates, the gene sei in 17 isolates and the gene sen in 31 isolates. The results imply diets prepared with such equipment as a vehicle for spreading enteropathogens and Staphylococcus spp. with resistance markers and enterotoxin-encoding genes relevant in the hospital.