title: Exploring Dangerous Connections between Klebsiella pneumoniae Biofilms and Healthcare-Associated Infections.
abstract: Healthcare-associated infections (HAI) are a huge public health concern, particularly when the etiological agents are multidrug resistant. The ability of bacteria to develop biofilm is a helpful skill, both to persist within hospital units and to increase antibiotic resistance. Although the links between antibiotic resistance, biofilms assembly and HAI are consensual, little is known about biofilms. Here, electron microscopy was adopted as a tool to investigate biofilm structures associated with increased antibiotic resistance. The K. pneumoniae strains investigated are able to assemble biofilms, albeit with different kinetics. The biofilm structure and the relative area fractions of bacteria and extracellular matrix depend on the particular strain, as well as the minimal inhibitory concentration (MIC) for the antibiotics. Increased values were found for bacteria organized in biofilms when compared to the respective planktonic forms, except for isolates Kp45 and Kp2948, the MIC values for which remained unchanged for fosfomycin. Altogether, these results showed that the emergence of antimicrobial resistance among bacteria responsible for HAI is a multifactorial phenomenon dependent on antibiotics and on bacteria/biofilm features.
authors.affiliation: Departamento de Engenharia Química, Instituto Superior Técnico, Universidade de Lisboa, Av Rovisco Pais, 1049-001 Lisboa, Portugal. maria.bandeira@tecnico.ulisboa.pt.
authors.forename: Maria
authors.initials: M
authors.lastname: Bandeira
authors.affiliation: Departamento de Engenharia Química, Instituto Superior Técnico, Universidade de Lisboa, Av Rovisco Pais, 1049-001 Lisboa, Portugal. pac@ist.utl.pt.
authors.forename: Patricia Almeida
authors.initials: PA
authors.lastname: Carvalho
authors.affiliation: Departamento de Microbiologia e Imunologia, ; iMed.UL, Faculdade de Farmácia, Universidade de Lisboa, Av Prof Gama Pinto, 1649-003 Lisboa, Portugal. aduarte@ff.ul.pt.
authors.forename: Aida
authors.initials: A
authors.lastname: Duarte
authors.affiliation: Departamento de Doenças Infeciosas, Instituto Nacional de Saúde Dr Ricardo Jorge, Av Padre Cruz, 1649-016 Lisboa, Portugal. maria.jordao@insa.min-saude.pt.
authors.forename: Luisa
authors.initials: L
authors.lastname: Jordao