Journal Article

Clostridium difficile infection: new developments in epidemiology and pathogenesis

Gerding, Dale N., Wilcox, Mark H., Rupnik, Maja

2009

Overview

Key Points This article reviews the latest clinical and fundamental research data on the important human pathogen Clostridium difficile . The clinical aspects of C. difficile infection (CDI) that are discussed include description of the disease spectrum and severity, and the signs, symptoms and clinical pathogenesis of CDI. An overview of the available treatment options for CDI is also given, including discussion of the problems associated with each therapeutic approach and new recommendations for treatment based on disease severity and the numbers of recurrences. CDI prevention is also discussed. Prevention methods include preventing acquisition of C. difficile spores by patients (using barrier and cleaning methods) and reducing the risk of symptomatic infection if the organism is encountered, primarily by avoidance of unnecessary use of antimicrobials. The laboratory diagnosis and characterization of C. difficile is also reviewed. The main detection methods and diagnostic tests, including the recent development of molecular testing and two-step diagnostic protocols, are discussed. The main molecular typing techniques used for C. difficile and the importance of antibiotic resistance testing are described. The changing epidemiology of CDI is reviewed. Important changes in the epidemiology of CDI have been observed over the past five years, especially increased infection rates in hospitals, increased disease severity, and increased rates and mortality with patient age. Most of these changes are presumed to be driven by presence of a new epidemic strain, C. difficile BI/NAP1/027. Changes in host populations (human versus animal populations with previous low risk), a possible increase in community associated disease, and new risk factors have also been observed. The known C. difficile virulence factors (TcdA and TcdB) and newly recognized virulence factors and their role in pathogenesis are discussed. The role of antibiotics in the development of CDI is discussed in relation to the susceptibility of C. difficile to antibiotics taken by the patient. The implication of the resistance of C. difficile to the fluoroquinolone class of antibiotics, and fluoroquinolones as an increasing risk factor for CDI, are discussed. Since 2001, the prevalence and severity of Clostridium difficile infection have increased substantially, and C. difficile is now considered to be one of the most important causes of health care-associated infections. Here, Rupnik, Wilcox and Gerding discuss the recent epidemiological changes in C. difficile infection and our current knowledge of C. difficile virulence factors. Clostridium difficile is now considered to be one of the most important causes of health care-associated infections. C. difficile infections are also emerging in the community and in animals used for food, and are no longer viewed simply as unpleasant complications that follow antibiotic therapy. Since 2001, the prevalence and severity of C. difficile infection has increased significantly, which has led to increased research interest and the discovery of new virulence factors, and has expanded and focused the development of new treatment and prevention regimens. This Review summarizes the recent epidemiological changes in C. difficile infection, our current knowledge of C. difficile virulence factors and the clinical outcomes of C. difficile infection.

• Publisher: Nature Publishing Group UK,Nature Publishing Group
• Subject: Animals / Anti-Bacterial Agents - therapeutic use / Antibiotics / Biomedical and Life Sciences / Blood / Causes of / Clinical outcomes / Clostridium difficile / Clostridium difficile - drug effects / Clostridium difficile - metabolism / Clostridium difficile - pathogenicity / Clostridium infections / Colon / Complications and side effects / Diagnosis / Diarrhea / Drug therapy / Enterocolitis, Pseudomembranous - drug therapy / Enterocolitis, Pseudomembranous - epidemiology / Enterocolitis, Pseudomembranous - microbiology / Enterocolitis, Pseudomembranous - prevention & control / Epidemiology / Health aspects / Health care / Hospitals / Humans / Infections / Infectious Diseases / Inflammatory bowel disease / Leukocytes / Life Sciences / Medical Microbiology / Microbiology / Models, Theoretical / Parasitology / Pathogenesis / Prevention / R&D / Research & development / review-article / Virology / Virulence / Virulence Factors - metabolism / Virulence Factors - physiology