Multirresistência em Acinetobacter baumannii e pesquisa de carbapenemases no Hospital e Maternidade Municipal de Uberlândia

Abstract

ABSTRACT The bacteria belonging to the genus Acinetobacter, are Gram-negative and immobile coccobacilli, are species that are isolated in several infectious sites and in hospital environment. They are usually associated with outbreaks of health care-related infections and can cause a variety of infections. They occur mainly in intensive care units (ICUs) and can extend the patient's hospitalization time, resulting in increased mortality, morbidity, and treatment costs. Outbreaks of this microorganism have been associated with multiple resistance to antimicrobial agents, especially carbapenems, which have been widely used to treat these infections. However, the resistance of A. baumannii to carbapenems is a reality, attributed mainly to the production of carbapenemases. With this, the objective of this study was to analyze the resistance profile of clinical samples of A. baumannii resistant to carbapenems and other antimicrobials, as well as to evaluate the production of Beta-lactamases, in a municipal hospital. The study was carried Hospital and Maternity Hospital Dr. Odelmo Leão Carneiro, located in the city of Uberlandia / MG. The samples were evaluated by antibiogram, originating from bloodstream infection from the years 2013 to 2017, and then performed the synergism test with ethylenediaminetetraacetic acid (EDTA), Cloxacillin and Boronic Acid Phenyl. Sixty-nine samples of bloodstream infections by carbapenem resistant A. baumannii were recovered. Of these, 75.4% were from patients admitted to a hospital ICU. Most of the samples came from blood cultures, from the years of 2013 and 2016, and the patients were mainly aged over 41 years. Samples showed resistance to most antimicrobials, but all were sensitive to Polimixin B and 82.5% to Tobramycin. The mechanism of resistance sought by the synergism test for the metallo-beta-lactamase type enzyme (MBL) was the most found, but 58% of the samples showed negative results. In association with the mechanisms of resistance, a difference in distributions was found in the years 2013 and 2016, with a higher expression of Klebsiella pneumoniae carbapenemase (KPC) and loss of porine in 2013, and a negative result in 2016. In individuals aged between 21 and 40 years, there was a greater expression of the MBL and KPC mechanisms, the latter being more frequent outside the ICUs. To better choose the treatment against A. baumannii infections, there is a need for epidemiological surveillance, a survey of hospital infection rates and the use of more severe microbiological criteria, including antimicrobial exchange and research on the main mechanisms of resistance expressed by bacteria associated with hospital infections.