Serratia marcescens resistente a carbapenêmicos: epidemiologia, avaliação genotípica e fenotípica

Abstract

Melo GVBP. Carbapenemic resistant Serratia marcescens: epidemiology, genotypic and phenotypic evaluation [thesis]. São Paulo: "Faculdade de Medicina, Universidade de São Paulo"; 2019. Serratia marcescens is an opportunistic agent, most often associated with nosocomial infection. It has high adaptability to the environment and ability to acquire antimicrobial resistance. This study is a retrospective cohort of patients colonized or infected with carbapenem-resistant Serratia marcescens (CrSm) between 2010 and 2013, admitted to the Instituto Central do Hospital das Clínicas de São Paulo (ICHC-FMUSP). Epidemiological data were collected through medical records and we analysed the isolates available in a strain bank. Risk factors for infection and sensitivity profile for broth microdilution were evaluated. We also investigated resistance mechanisms through PCR, PFGE and Whole Genome Sequencing.Sixty-three patients were included, 43 colonized and 20 with infection, including 12 from the bloodstream. Polymyxin use, renal failure, and catheter use within 30 days prior to isolation of CrSm and haematopoietic stem cell transplantation were correlated with infection in the univariate analysis and polymyxin use was the only one that remained in the analysis. multivariate. Forty-two isolates were analyzed from 35 patients and 3 environmental samples. MIC testing revealed 4 carbapenem-sensitive isolates, 42% sensitivity to amikacin and 27% sensitivity to tigecycline. Twenty-five of the 42 isolates carried blaKPC-2, which was the most frequent carbapenemase. An isolate carried blaNDM. The result of the PFGE indicates that there is a predominant clone, to which 71% of the isolates belong.We conclude that the LISTA DE ABREVIATURAS E SIGLAS A/S2 Ampicillin/Sulbactam AMI Amicacina AVC Acidente vascular cerebral AVCI Acidente vascular cerebral isquêmico AZT Aztreonam BCP Broncopneumonia BHI Brain Heart Infusion BHR Broad host ranges CI Cateter implantável CIM Concentração inibitória mínima