Strategies for combating bacterial biofilm infections

Formation of biofilm is a survival strategy for bacteria and fungi to adapt to their living environment, especially in the hostile environment. Under the protection of biofilm, microbial cells in biofilm become tolerant and resistant to antibiotics and the immune responses, which increases the difficulties for the clinical treatment of biofilm infections. Clinical and laboratory investigations demonstrated a perspicuous correlation between biofilm infection and medical foreign bodies or indwelling devices. Clinical observations and experimental studies indicated clearly that antibiotic treatment alone is in most cases insufficient to eradicate biofilm infections. Therefore, to effectively treat biofilm infections with currently available antibiotics and evaluate the outcomes become important and urgent for clinicians. The review summarizes the latest progress in treatment of clinical biofilm infections and scientific investigations, discusses the diagnosis and treatment of different biofilm infections and introduces the promising laboratory progress, which may contribute to prevention or cure of biofilm infections. We conclude that, an efficient treatment of biofilm infections needs a well-established multidisciplinary collaboration, which includes removal of the infected foreign bodies, selection of biofilm-active, sensitive and well-penetrating antibiotics, systemic or topical antibiotic administration in high dosage and combinations, and administration of anti-quorum sensing or biofilm dispersal agents. Antibiotics alone are often ineffective in the treatment of bacterial biofilm infections and new strategies are needed. Once bacteria shift from their free-swimming state to the structured community of a biofilm, they become much harder to kill with conventional antibiotic regimens. A review by Zhi-Jun Song and colleagues at Denmark’s University Hospital of Copenhagen explores the challenges of diagnosing and eliminating biofilms that form on the surface of implanted medical devices. At present, the best solution is early detection followed by aggressive treatment with multiple antibiotics and removal of the device in question. However, recent research suggests other possible solutions, including drugs that interfere with communication between bacteria or disrupt their ability to anchor to surfaces, and viruses that specifically infect and kill biofilm-forming microbes.