Culturas de vigilância de resistência de pacientes internos em unidade de terapia intensiva do hospital referência em doenças infecciosas do Rio Grande do Norte

Abstract

Epidemiological surveillance cultures are a set of techniques for isolation and identification of microorganisms resistant to antimicrobials in colonized individuals in order to prevent outbreaks and their transmission between them. In this work, samples were collected from the rectal, axillary and nasal sites of 24 patients in the ICU of the Rio Grande do Norte state reference hospital in infectious diseases, in order to describe the bacterial profile in this unit. Forwarded to the Mycobacterial Laboratory (LABMIC) / UFRN, the specimens were isolated as to their etiology and bacterial resistance. For Gram-negative bacilli (BGN) strains resistant to carbapenems, their minimum inhibitory concentration (MIC) against Imipenem and Polymyxin B was determined and conventional PCRs were performed in order to characterize the presence of the blaNDM, blaIMP-1, blaIMP-2, blaVIM-1, blaVIM-2, blaOXA-23, blaOXA-48, blaKPC and mcr-1 genes. For Gram-positive cocci (CGP) characterized as resistant to Oxacillin, the determination of the MIC for Vancomycin was performed by Etest®. As a result, 62 bacteria with a resistance profile were isolated and identified, with 48 (77%) BGN and 14 (23%) CGP. Among BGNs, 54% were producers of extended-spectrum betalactamases. All CGPs showed resistance to Oxacillin and sensitivity to Vancomycin. Nineteen samples (09 Pseudomonas aeruginosa, 06 Acinetobacter spp. and 04 Klebsiella pneumoniae) showed resistance to carbapenems (Rcarb). For Rcarb genes, 04 (21%) samples presented the blaNDM-1 gene, 01 K. pneumoniae, 01 Acinetobacter spp. and 02 P. aeruginosa. The blaKPC gene was found in 08 (42.1%) samples: 03 K. pneumoniae, 04 P. aeruginosa and 01 Acinetobacter spp. It is noticed that the phenotypic and genotypic characteristics of the bacteria identified in this work are responsible for severe therapeutic failures, leading to an increase in patients' morbidity and mortality, demonstrating the complexity of the bacterial resistance issue.