Background
During the COVID-19 pandemic, the burden of nosocomial infections caused by MDR pathogens has caused a shortage of polymyxins. Thus, we evaluated the in vitro synergism and antibiofilm activity of antimicrobial combinations and propose a test kit for synergism against carbapenem-resistant Acinetobacter baumannii (CRAB).
Methods
Fifty-six CRAB isolates were tested for synergy between meropenem, gentamicin and ampicillin/sulbactam. MICs were determined by broth microdilution. Synergism was tested using chequerboard analysis, followed by a time–kill curve. Additionally, minimum biofilm eradication concentration was determined and the antibiofilm activity of the combinations was evaluated by MTT assay and biomass reduction. A test kit was developed for routine laboratory testing to detect synergism.
Results
All CRAB isolates were resistant to gentamicin and ampicillin/sulbactam. Chequerboard synergism occurred against 75% of the isolates. Meropenem + ampicillin/sulbactam was the most frequent combination with synergism (69%), followed by ampicillin/sulbactam + gentamicin (64%) and meropenem + gentamicin (51%). All combinations presented only bacteriostatic activity and no bactericidal or antibiofilm effects. The routine laboratory test showed 100% accuracy compared with other in vitro assays.
Conclusions
Our study demonstrates the potential role of antibiotic combinations against planktonic bacteria. In vitro synergism is possible and can be an alternative treatment for patients with CRAB infection during a polymyxin shortage.
Introdução. Casos que associam COVID-19 e Síndrome de Guillain-Barré (SGB) em pacientes críticos foram raramente evidenciados na literatura. Objetivo. Nesse contexto, esse artigo (aprovado pelo Comitê de Ética em Pesquisa, 56769722.7.0000.0020) visa relatar o caso de JIB. Relato de Caso. Paciente masculino, 75 anos, internado na Unidade de Terapia Intensiva, teve o diagnóstico de SGB confirmado pelos achados clínicos (rápida instalação da tetraparesia, tetraplegia flácida bilateral simétrica e déficits sensoriais), pela hiperproteinorraquia no líquido cefalorraquidiano (LCR) e pela polirradiculoneuropatia desmielinizante aguda na eletroneuromiografia. Após o diagnóstico, recebeu tratamento com imunoglobulina 0.4g/Kg/dia por 5 dias e, na alta hospitalar, já apresentava resolução completa dos sintomas.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.