Monitoramento de Corynebacterium striatum em hospital universitário da região metropolitana do Rio de Janeiro: aspectos epidemiológicos, microbiológicos e do potencial de virulência

• Autor(a) principal: Gusmão, Letícia Nunes Marones de
• Data de Publicação: 2018
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UERJ
• Texto Completo: http://www.bdtd.uerj.br/handle/1/14387
• topic: Corynebacterium striatum; Health-care associated infections; Virulence; Nosocomial outbreak; Virulência (Microbiologia); Corynebacterium striatum Epidemiologia; Corynebacterium striatum Microbiologia; Virulência (Microbiologia); Infecção hospitalar Epidemiologia; Infecções por Corynebacterium; Hospital Universitário Pedro Ernesto Aspectos da Saúde; CNPQ::CIENCIAS BIOLOGICAS::MICROBIOLOGIA

Corynebacterium striatum has been associated with an increasing number of cases of healthcare-associated infections (HAI), representing an important issue, as they increase mortality and morbidity rates and prolong hospitalizations, resulting, thus, in economic and social damages.Virulence factors such as resistance to antimicrobial agents, ability to adhere to diverse surfaces and to yield biofilm, slime, hydrolytic and proteolytic enzymes may contribute to bacterial pathogenicity. We aimed to analyze, retrospectively and prospectively, the epidemiological, microbiological and virulence aspects of C. striatum strains from the Hospital of the University of the State of Rio de Janeiro - HUPE / UERJ, identified during the period of August/2009 to December/2016. At first we confirmed the efficacy (100% compatibility with 16SrRNA and rpoB gene sequencing) of the MALDI-TOF technique and the screening scheme proposed by the LDCIC/UERJ for C. striatum identification. In the other hand, the semi-automated API Coryne System has presented very low scores with the possibility of failure to identify C. striatum. Eighty nine C. striatum strains were sent from HUPE/UERJ to LDCIC for identification, with the highest number of isolates in 2011/2012 (48.31%). The general ICU and UCIPG section had the highest percentages of isolated C. striatum strains (17.98% and 13.48%). Most of the samples were isolated from the respiratory tract (51.69%) and blood (16.85%). The clonality of 18 samples were investigated by PFGE. Ten PFGE types (I to X) were identified, with eight of them (I, II, V-X) related to blood samples and catheters. Seventy two samples were submitted to the disc diffusion antimicrobial susceptibility test and 90.3% had a multidrug resistance (MDR) profile. Vancomycin was the only antimicrobial agent with 100% bacterial sensitivity. The ermX, aphA1 and cmx resistance genes were investigated by conventional PCR in four MDR samples (pulse I, II, V) and two MDS samples (pulse III and IV). All MDR samples showed amplicons for all genes whereas MDS samples were negative for all genes. All tested samples has showed slime production in the Congo Red Medium and yielded biofilm on the polyurethane catheter and polystyrene surfaces, except 2401 BR-RJ/2012-MDR strain. Ultrastructural analysis by scanning electron microscopy has demonstrated mature biofilms after 48 hours of incubation, allowing observes hollow voids and the production and accumulation of extracellular material. The results indicate that MDR and MDS C. striatum biofilm producers were responsible for severe infections, including infections in patients using invasive medical devices, at HUPE/UERJ. Our data emphasize that C. striatum should not be underestimated, neglected or dismissed as contaminants by health professionals. This infectious agent should be take into account as a pathogen related to health-care associated infections (HAI) in Brazil and efforts should be made to monitoring and elaborate strategies for the prevention, control and treatment of this corynebacteriosis.