Emerging Issues and Initial Insights into Bacterial Biofilms: From Orthopedic Infection to Metabolomics

Abstract

Bacterial biofilms, enigmatic communities of microorganisms enclosed in an extracellular matrix, still represent an open challenge in many clinical contexts, including orthopedics, where biofilm-associated bone and joint infections remain the main cause of implant failure. This study explores the scenario of biofilm infections, with a focus on those related to orthopedic implants, highlighting recently emerged substantial aspects of the pathogenesis and their potential repercussions on the clinic, as well as the progress and gaps that still exist in the diagnostics and management of these infections. The classic mechanisms through which biofilms form and the more recently proposed new ones are depicted. The ways in which bacteria hide, become impenetrable to antibiotics, and evade the immune defenses, creating reservoirs of bacteria difficult to detect and reach, are delineated, such as bacterial dormancy within biofilms, entry into host cells, and penetration into bone canaliculi. New findings on biofilm formation with host components are presented. The article also delves into the emerging and critical concept of immunometabolism, a key function of immune cells that biofilm interferes with. The growing potential of biofilm metabolomics in the diagnosis and therapy of biofilm infections is highlighted, referring to the latest research.

Global Trends in Orthopedic Biofilm Research: A Bibliometric Analysis of 1994-2022

“… 8 This study also highlighted emerging non-invasive techniques (eg, disclosing agents and biomarkers α-defensin) and the need for standardization to improve diagnostic accuracy and clinical translation. A recent review 53 discussed the interdisciplinary efforts required to combat biofilm infections in orthopedic medicine, combining insights from microbiology, immunology, biochemistry, and materials science to develop innovative diagnostic and therapeutic approaches. This study delved into the intricate processes behind biofilm formation, such as bacterial dormancy and infiltration into host cells and bone structures, which contribute to the chronicity of infections and their resistance to conventional antibiotics.…”

Research and Application of Chitosan Nanoparticles in Orthopedic Infections

“…Biofilms are microbial communities embedded within polymeric extracellular matrixes that can attach to biotic and abiotic surfaces ( Figure 2 ). 25 Upon implant placement, bacteria can attach to the implant surface and form biofilms at the implant site, resulting in local microbial infections. 26

Figure 2 Bacterial biofilm adheres to the bone plate and continuously releases planktonic bacteria, leading to infections that cannot be completely cured.

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