Biofilm Infections

Approximately 60% of all hospital-associated infections, over one million cases per year, are due to biofilms that have formed on indwelling medical devices. Device-related biofilm infections increase hospital stays and add over one billion dollars/year to U.S. hospitalization costs. Since the use and the types of indwelling medical devices commonly used in modern healthcare are continuously expanding, especially with an aging population, the incidence of biofilm infections will also continue to rise. The central problem with microbial biofilm infections of foreign bodies is their propensity to resist clearance by the host immune system and all antimicrobial agents tested to date. In fact, compared to their free floating, planktonic counterparts, microbes within a biofilm are 50 – 500 times more resistant to antimicrobial agents. Therefore, achieving therapeutic and non-lethal dosing regimens within the human host is impossible. The end result is a conversion from an acute infection to one that is persistent, chronic, and recurrent, most often requiring device removal in order to eliminate the infection. This text will describe the major types of device-related infections, and will explain the host, pathogen, and the unique properties of their interactions in order to gain a better understanding of these recalcitrant infections.

Biofilms in Infection and Disease Control: A Healthcare Handbook outlines the scientific evidence and rationale for the prevention of infection, the role biofilms play in infection control, and the issues concerning their resistance to antimicrobials. This book provides practical guidance for healthcare and infection control professionals, as well as students, for preventing and controlling infection. Biofilms are the most common mode of bacterial growth in nature. Highly resistant to antibiotics and antimicrobials, biofilms are the source of more than 65 percent of health care associated infections (HCAI), which, according to the WHO, affect 1.4 million people annually. Biofilms are involved in 80 percent of all microbial infections in the body, including those associated with medical devices such as catheters, endotracheal tubes, joint prostheses, and heart valves. Biofilms are also the principle causes of infections of the middle-ear, dental caries, gingivitis, prostatitis and cystic fibrosis. Importantly, biofilms also significantly delay wound healing and reduce antimicrobial efficiency in at-risk or infected skin wounds. Provides specific procedures for controlling and preventing infection Includes case studies of HCAI, and identifies appropriate treatments Presents national government standards for infection prevention and control Includes extensive references and links to websites for further information

This book reviews the current concepts in biofilm formation and its implications in human health and disease. The initial chapters introduce the mechanisms of biofilm formation and its composition. Subsequently, the chapters discuss the role of biofilm in acute and chronic infections. It also explores the pivotal role of both innate and adaptive immunity on the course of biofilm infection. In addition, the book elucidates the bacterial biofilm formation on implantable devices and the current approaches to its treatment and prevention. It analyzes the possible relationship between antimicrobial resistance and biofilm formation. Finally, the book also summarizes the current state-of-the-art therapeutic approaches for preventing and treating biofilms. This book is a useful resource for researchers in the field of microbiology, clinical microbiology, and also medical practitioners.

Rather than existing in a planktonic or free-living form, evidence indicates that microbes show a preference for living in a sessile form within complex communities called biofilms. Biofilms appear to afford microbes a survival advantage by optimizing nutrition, offering protection against hostile elements, and providing a network for cell-to-cell signaling and genetic exchange. Biofilms, Infection, and Antimicrobial Therapy provides an in-depth exploration of biofilms, offering broad background information, as well a detailed look at the serious concerns to which biofilm-associated infections give rise. Prosthetic device infections, such as those involving artificial heart valves, intravascular catheters, or prosthetic joints, are prime examples of biofilm-associated infections. With the increasing use of such devices in the modern practice of medicine, the prevalence of these infections is expected to increase. Unfortunately, one of the most troubling characteristics of microbes found in biofilms is a profound resistance to antimicrobial agents. As biofilm-associated infections are particularly difficult to treat, they result in significant mortality, morbidity, and increased economic burden. Clearly, a better understanding of the pathogenesis of these infections and improved means for prevention and treatment are urgently needed! InBiofilms, Infection, and Antimicrobial Therapy, Drs Pace, Rupp, and Finch assemble the contributions of more than 50 of the world’s leading authorities on microbial biofilms who present recent findings on antibacterial tolerance and bacterial persistence associated with biofilms and discuses the implications of those findings with regard to human health. They explore the molecular mechanisms of bacterial adherence, biofilm formation, regulation of biofilm maintenance, and cell-to-cell communication and present the latest information on various treatment protocols that should aid physicians in the treatment of these refractory and often difficult-to-treat infections.

Throughout the biological world, bacteria thrive predominantly in surface-attached, matrix-enclosed, multicellular communities or biofilms, as opposed to isolated planktonic cells. This choice of lifestyle is not trivial, as it involves major shifts in the use of genetic information and cellular energy, and has profound consequences for bacterial physiology and survival. Growth within a biofilm can thwart immune function and antibiotic therapy and thereby complicate the treatment of infectious diseases, especially chronic and foreign device-associated infections. Modern studies of many important biofilms have advanced well beyond the descriptive stage, and have begun to provide molecular details of the structural, biochemical, and genetic processes that drive biofilm formation and its dispersion. There is much diversity in the details of biofilm development among various species, but there are also commonalities. In most species, environmental and nutritional conditions greatly influence biofilm development. Similar kinds of adhesive molecules often promote biofilm formation in diverse species. Signaling and regulatory processes that drive biofilm development are often conserved, especially among related bacteria. Knowledge of such processes holds great promise for efforts to control biofilm growth and combat biofilm-associated infections. This volume focuses on the biology of biofilms that affect human disease, although it is by no means comprehensive. It opens with chapters that provide the reader with current perspectives on biofilm development, physiology, environmental, and regulatory effects, the role of quorum sensing, and resistance/phenotypic persistence to antimicrobial agents during biofilm growth.

Bacterial biofilm is a complex structure with diverse bacterial cells in a highly organized and ordered group within a matrix of extracellular polymeric substances they produce. Microbes attach to surfaces to develop biofilms, a sophisticated process regulated by factors such as nutritional status and biotic/abiotic surface features. An established biofilm structure mainly comprises bacterial cells, proteins, nucleic acid, and exo-polysaccharides that are extracellular macromolecules excreted as tightly bound layers in microbes, providing a perfect niche for bacteria to exchange genetic material between cells. In addition, bacterial cells in the matrix also communicate via quorum sensing, which greatly impacts biofilm processes. Under clinical circumstances, bacterial biofilm shows great resistance to antibiotics, disinfectants, and body defense systems, making it difficult for clinicians to eradicate and facilitate many infectious disease processes, leading to chronic infections of patients with long-term hospitalization and high mortality rates. Therefore, it is very important to understand the recent advances in forming, regulating, and eradicating biofilms in human infections to better prevent, control, and treat biofilm infections in humans. Written by an international team of basic and clinical researchers, the chapters of this book provide novel insights and advanced knowledge for life science researchers, clinical researchers, doctors, and other interested readers on some of the latest developments in biofilms.

This book will cover both the evidence for biofilms in many chronic bacterial infections as well as the problems facing these infections such as diagnostics and treatment regimes. A still increasing interest and emphasis on the sessile bacterial lifestyle biofilms has been seen since it was realized that that less than 0.1% of the total microbial biomass lives in the planktonic mode of growth. The term was coined in 1978 by Costerton et al. who defined the term biofilm for the first time.In 1993 the American Society for Microbiology (ASM) recognised that the biofilmmode of growth was relevant to microbiology. Lately many articles have been published on the clinical implications of bacterial biofilms. Both original articles and reviews concerning the biofilm problem are available.

The number of patients affected by and dying from what can be considered as a "biofilm disease" is higher than heart disease and cancer combined. Thus, this is a hugely important work that describes the molecular mechanisms of cell-to-cell communication among bacterial cells in a biofilm, the development of antibiofilm inhibitors such as quorum-sensing inhibitors, and the use of biofilm inhibitors to prevent and treat bacterial infections in humans and other animals.