Ocorrência de Staphylococcus sp. em ambiente hospitalar, caracterização de superfícies e adesão de Staphylococcus aureus em sondas nasoenterais de poliuretano e silicone

• Ano de defesa: 2007
• Autor(a) principal: Lima, Júnia Cápua de
• Orientador(a): Andrade, Nélio José de
• Banca de defesa: Coimbra, Jane Sélia dos Reis , Mendonça, Regina Célia Santos , Pinto, Cláudia Lúcia de Oliveira
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Mestrado em Ciência e Tecnologia de Alimentos
• Departamento: Ciência de Alimentos; Tecnologia de Alimentos; Engenharia de Alimentos
• País: BR
• Palavras-chave em Português: Adesão bacteriana; Staphylococcus spp.; Sondas nasoenterais
• Palavras-chave em Inglês: Bacterial adhesion; Staphylococcus spp.; Nasoenteral tubes
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::CIENCIA E TECNOLOGIA DE ALIMENTOS::CIENCIA DE ALIMENTOS::MICROBIOLOGIA DE ALIMENTOS
• Link de acesso: http://locus.ufv.br/handle/123456789/2827

Staphylococcus species were isolated and identified from enteral diets, ambient air from the Intensive Care Unit (ICU) and from the enteral nutrition preparation room, handlers of feeding tubes and diets, preparation surfaces, patient s nasal mucous and polyurethane and silicone nasoenteral tubes used in rooms of a municipal hospital. The isolates were identified using the API Staph kit (BioMérieux®, France). Sensibility of isolates to antimicrobial agents was evaluated by the detection method using paper discs impregnated with the following antibiotics: ciprofloxacin-CIP (5 µg), amikacin-AMI (30 µg), clindamycin-CLI (2 µg), clarithromycin-clar (15 µg), ceftriaxone-CRO (30 µg), ceftazidime-CAZ (30 µg), imipenem- IMP (10 µg), oxacylin-OXA (1 µg), sultamicillin- ampicillin and sulbactam-APS (10/10 µg) and vancomycin-Van (30 µg). Specimens of polyurethane and silicone tubes were analyzed for rupture tension and stretching (Instron Testing Machine), hydrophobicity analysis of internal surfaces by contact angle measurement (goniometer) and surface roughness and topography by atomic force microscopy. Adhesion of Staphylococcus aureus isolates to tube internal surfaces was evaluated by standard plate count and scanning electron microscopy. High Staphylococcus sp counts were confirmed in the ICU air (2.15 ± 0.36 log UFC.m-3), in the diet preparation room (1.64 ± 0.17 log UFC.m-3) and in the used tubes (between 6.88 log UFC.cm-2 and 7.38 log UFC.cm-2). S. aureus was the most frequent species amongst the isolates (52.44%), with the largest percentage in nasoenteral tubes (28.05%). Among 48 isolates analyzed, 44 were sensitive to imipenem, a carbapenemic antibiotic, corresponding to 91.6%, and one isolate was sensitive to the glycopeptide vancomycin (2.1%). However, 47 (87.5%) isolates were resistant to the antimicrobial ceftazidime, in the cephalosporin class (cephens). The polyurethane tube was more resistant than the silicone one in the rupture tension and stretching tests and was shown hydrophilic (Ow = 50.2 ± 0.61), whereas the silicone tube was hydrophobic (Ow = 74.6 ± 1.30). The polyurethane tube showed higher mean surface roughness than the silicone one, with mean roughness (Ra) of 2.87 nm, with maximum difference between the highest and the lowest point (Rt) of 53.90 nm. There was occurrence of irregularities such as protuberances, fissures, rifts and holes on the surface photomicrographies. The microscopic analysis showed that S. aureus was capable to adhere to both surfaces. After three days of tests, S. aureus mean counts were not different (p>0.05), reaching 1.11 log UFC.cm-2 for polyurethane and 0.99 log UFC.cm-2 for silicone. The importance of the several factors involved in microorganism adherence to surfaces still has to be better and more clearly established. The use of models simulating bacterial contamination of polymers is crucial for new developments. New polymers should be researched and tested for the production of nasoenteral tubes in order to reduce or inhibit bacterial adhesion by modifying physicochemical surface characteristics.