JUL 15, 2015 2:59 PM PDT

Diversity of Gut Microbiota Predicts Resistance to Clostridium difficile

WRITTEN BY: Sarah Hertrich
Clostridium difficile is most commonly referred to as a healthcare-associated infection (HAI), with at risk-populations including older adults who are currently receiving medical care or who are taking antibiotics. According to the CDC, in 2011 there were approximately 50,000 infections caused by C. difficile. Of the persons infected 29,000 died within 30 days of their initial diagnosis. C. difficile is a type of spore-forming bacteria that produces two types of enterotoxins. It accounts for 15-25 % antibiotic associated diarrhea (AAD). C. difficile infection can also result in pseudomembranous colitis (PMC), toxic megacolon, perforations of the colon, sepsis and sometimes death. It is currently regarded as the leading cause of hospital-acquired infections in the US.
Clostridium difficile is the leading cause of hospital acquired infections in the United States.
Researchers at the University Of Maryland School Of Medicine have recently discovered that certain species present in the gut may help protect colonization by C. difficile. When the normal microflora in the gut are wiped out by antibiotics, C. difficile has the opportunity to colonize the gut and produce enterotoxins, which is why antibiotic treatment is considered a major risk factor for acquiring a C. difficile infection. In their study, researchers administered one of 7 different antibiotics in mice order to alter the indigenous bacteria present in the gut. Following a 24 h recovery period, mice were challenged with C. difficile spores. Fecal samples from the treated mice were collected on the day of the C. difficile challenge as well as the day after the challenge. Fecal samples were processed to enumerate aerobic as well as anaerobic bacteria present in the samples followed by DNA sequencing. The research team used relative abundance data to build a machine learning regression model to predict the levels of C. difficile that could be found in the fecal samples 24 h following the challenge.

Bacterial populations including Porphyromonadaceae, Lachnospiraceae, Lactobacillus, and Alistipes were reported to be protective against C. difficile colonization and Escherichia and Streptococcus species were found to help enhance C. difficile colonization. One species, Akkermansia, was found to have a strong dependency on other members of the microbiota. The authors of the study concluded that individual bacterial populations do not drive colonization resistance to C. difficile. Instead, authors believe that different bacterial species present in the gut work together to mediate colonization resistance against C. difficile.

The findings of this study could lead to better methods to assess the risk of a particular patient to acquire a hospital acquired infection, such as C. difficile. This would require sequencing of the patient's gut microbiota to determine what bacterial species are missing and added back via probiotic treatment. This method could be used as a pre-screening preventative, similar to those used to screen for MRSA in hospital settings upon admission of a new patient.

Sources: CDC, American Society for Microbiology
About the Author
  • I am a postdoctoral researcher with interests in pre-harvest microbial food safety, nonthermal food processing technologies, zoonotic pathogens, and plant-microbe interactions. My current research projects involve the optimization of novel food processing technologies to reduce the number of foodborne pathogens on fresh produce. I am a food geek!
You May Also Like
DEC 05, 2019
Drug Discovery & Development
DEC 05, 2019
New Injection that Treats Peanut Allergy
Peanut allergies affect between 1 and 3% of the US population. Associated with a heightened risk of severe anaphylactic reactions, oral immunotherapy is th...
DEC 09, 2019
Genetics & Genomics
DEC 09, 2019
Researchers Rewire E. coli to Consume Carbon Dioxide
Milo et. al.   Researchers have genetically rewired the metabolism of Escherichia coli to be autotrophic, using formate (COOH) as a food sou...
DEC 27, 2019
Microbiology
DEC 27, 2019
Using a Cancer Drug to Fight Antibiotic-Resistant Pathogens
It takes a long time for a drug to be approved for use in humans; repurposing existing drugs is one way to get around that hurdle....
JAN 31, 2020
Microbiology
JAN 31, 2020
Wuhan Coronavirus: WHO Declares Global Emergency
Since the first cases of a novel Coronavirus were detected in Wuhan, China a few weeks ago, the virus has spread around the globe....
FEB 04, 2020
Microbiology
FEB 04, 2020
Revealing How a Common Virus Evades the Immune System
The human metapneumovirus (HMPV) might now be well-known, but it is the second biggest cause of respiratory infections....
FEB 17, 2020
Immunology
FEB 17, 2020
Another HIV vaccine attempt fizzles out
Years of work and over $100 million in study costs have been abandoned after an HIV-vaccine tested in South Africa failed to protect treated individuals ag...
Loading Comments...