masterThesis
Caracterização fenotípica e molecular da resistência antimicrobiana em Acinetobacter sp: ênfase aos β-lactâmicos
Fecha
2015-05-14Registro en:
LOPES, Maria Carolina Soares. Caracterização fenotípica e molecular da resistência antimicrobiana em Acinetobacter sp: ênfase aos β-lactâmicos. 2015. 124 f. Dissertação (Mestrado em Ciências Biológicas) – Programa de Pós-Graduação em Ciências Biológicas. Universidade Federal do Rio Grande do Norte, 2015.
Autor
Lopes, Maria Carolina Soares
Resumen
The Hospital Infections are the main cause of morbidity and mortality in hospitalized patients. Isolations reports of multidrug-resistant Acinetobacter from clinical specimens obtained from hospitalized patients and the hospital are more frequent. Thus, this study aimed to characterize molecular and phenotypic isolated from Acinetobacter sp. for susceptibility to antimicrobials, with emphasis on β-lactams. Clinical isolates and hospital surfaces isolates of Acinetobacter sp. were collected in four hospitals located in the city of Natal-RN, from March 2013 to March 2014. The identification of the isolates was carried out by standard laboratory tests, the MALDI-TOF system and research blaOXA-51 gene. The antimicrobial susceptibility was evaluated by disk diffusion method. For tigecycline drug, the minimum inhibitory concentration (MIC) was determined by the E-test. Furthermore, screening tests were performed for AmpC enzymes, and ESBL Carbapanemases and research of genes for carbapenemases (IMP-1, VIM-1, NDM-1, KPC-2, OXA-23, OXA-24, OXA- 58, OXA-143) by technique of polymerase chain reaction (PCR). Factors associated with the presence of multidrug resistance were also studied. 242 samples were studied, with 155 clinical samples and 87 samples of hospital surfaces. The mean occurrence of Acinetobacter sp. in the hospitals studied was 7.6% in clinical sample and 12.8% in samples of hospital surfaces. In this, the sites most contaminated by this bacterium was the bench procedures and the floor. Two hundred and thirty seven samples (97.9%) and 198 (81.8%) of the samples were identified as A.baumannii by conventional tests and MALDI-TOF, respectively, and the positivity of blaOXA-51 gene occurred in 235( 97.1%) samples. Most, 141 (58.2%) of the strains of Acinetobacter sp. They were resistant to three or more classes of antibiotics. A positive test for the detection of enzyme AmpC were 5.8% in Test Hodge was 61.1% and the β-lactamase Metallo was 78.5% detection test. No samples proved producing ESBL. The genes most commonly found were the blaOXA-23 and blaOXA-143. The use of invasive devices (p = 0.001), the amount of antimicrobials used (p = 0.01), the ICU stay (p = 0.008) and hospitalization in a public hospital (p = 0.05) presented themselves as factors associated with the acquisition of Acinetobacter sp. strains MDR. Death was the most frequent clinical outcome (p <0.001) in patients with infection by these strains. The high number of multidrug-resistant Acinetobacter antimicrobial, isolated from patients and especially of inanimate surfaces in hospitals is disturbing. This scenario may compromise both the empirical treatment of seriously ill patients as the hospital infection control strategies.