‘Superbug’ Colonizes Colon
Ashley Mood (5 PM Micro) is worried about the stuff we eat. We have mentioned Clostridium difficile in class previously, and indicated how antibiotic therapy can render susceptible patients even more susceptible, due to elimination of the normal intestinal microbial flora. Here is Ashley with her dire report:
Nosocomial infections are increasingly becoming a patient safety issue in hospitals. Microbial pathogens adapt to hospital settings and proliferate in this environment after infecting patients vulnerable to their effects. The pathogen Methicillin Resistant Staphylococcus aureus (MRSA), has acquired a resistance to antimicrobial agents and has enhanced survival properties which has presented health care professionals with a dilemma when treating patients. Recently, a spore forming bacteria known as Clostridium difficile has fallen under this category of infections.
C. difficile is the agent that causes a wide spectrum of gastrointestinal diseases known as C.difficile infections or CDI. Antibiotics that interrupt a person’s normal gastrointestinal microbiota bring about these infections. CDI ranges from mild diarrhea to life threatening pseudomembranous colitis which is a chornic usually life threatening gastrointestinal disease. This ‘superbug’ accounts for about $3.2 billion each year in health care costs just in the United States alone.
In research published in a journal, PLoS Pathogens, Dena Lyras and Glen Carter from Monash University have demonstrated how a mutation that occurs naturally in C.difficile can cause this potentially life threatening gastrointestinal disease in hospital patients who are receiving antibiotic treatment. They say that the C.difficile can colonize in the colon because antibiotics diminish the protective bacteria that is usually there. Dangerous strains of C.difficile are produced when a mutation wipes out anti-sigma factor TcdC, an inbuilt disease regulator. This mutation is an important factor in the development of hypervirulence in C. difficile infections because the mutation leads to increased production of toxins. These particular strains of disease are hypervirulent as well as resistant to broad-spectrum antibiotics. The broad-spectrum class of drugs that the reasearchers used was fluoroquinolones. They found that C.difficile is highly resistant to this class of drugs. C.difficile is also causing disease in children and pregnant women who previously were not at risk.
With C.difficile becoming a major health concern, the researchers conducted a study to determine how these superbugs develop in order to learn how to treat them. In the study they were able to better understand how they develop, how they cause disease, and why they are so harmful and the next step is to develop new ways to combat the rising rates of infection due to C.difficile.