Estudo de portadores nasais de Staphylococcus aureus e do risco de infecção sistêmica em pacientes sob regime de hemodiálise em dois centros de diálise da Grande Vitória, ES

• Autor(a) principal: Araujo, Manuela Tedesco
• Data de Publicação: 2011
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Espírito Santo (riUfes)
• Texto Completo: http://repositorio.ufes.br/handle/10/5952
• topic: Hemodialysis; Nasal carriage; Vancomycin; Colonização nasal; Vancomicina; Doenças Infecciosas e Parasitárias; Staphylococcus aureus; Hemodiálise; 61

Staphylococcus aureus is a pathogen that has the ability to colonize approximately half of the patients undergoing hemodialysis and also is the main cause of infections in these patients. The nasal colonization by S. aureus is a risk factor for developing bacteremia and, despite the great importance in determining the colonization status of patients undergoing hemodialysis, there is no currently a standardized methodology to classify such patients. This study was designed in order to: determine the status of nasal colonization of patients undergoing hemodialysis in two dialysis centers; to improve the reference methodology to classify the status of nasal colonization and assess the risk conferred by nasal colonization in the development of bacteriemia. The study included 219 patients of which 22.8% were nasal carriers of S. aureus. All 182 samples of S. aureus isolates were sensitive to oxacillin and vancomycin but 2.7% (5 / 182) samples were heteroresistant to vancomycin. The classification of the nasal carriage status was performed in 178 patients of which 22.5% were nasal carriers of S. aureus [20% (8 / 40) with persistent and 80% (32/40) intermittent carriers] and 77.5% (138/178) non-carriers. Among the types of colonization, only persistent nasal colonization was substantially associated with the development of bacteremia caused by S. aureus conferring a risk of 17.6% (p = 0.05). The use of fistula demonstrated a protective effect featuring 7% (p = 0.00) and 11% (p = 0.01) the risk conferred by the use of the catheter on the development of bacteremia caused by S. aureus or other microorganisms, respectively. Also, the use of a protocol with seven weekly collections showed an excellent correlation with the reference method (k = 0.834) to distinguish the types of nasal carriers and had a PPV and PNV equal to 100% to differentiate patients with persistent and intermittent colonization, therefore it can be used as an alternative to the reference protocol for screening S. aureus nasal carriers and be used as a surveillance measure. Given the high risk conferred by persistent colonization, our results suggest that classification of nasal carriers is a very important measure to minimize the risk for development of bacteraemia in patients undergoing hemodialysis