Wisdom Wednesday: What allows C. difficile to survive so well in the gut?

Clostridium difficile is a particularly hardy type of bacteria, which is very difficult to treat. It often affects people during a hospital stay – especially if they have taken antibiotics. Why is it this resilient, and does knowing this lead to better treatments?

According to some experts, Clostridium difficile infections are ever on the rise and becoming increasingly difficult to treat. This means that researchers need to find new and better ways of targeting this stubborn bacterium. Among other symptoms, C. difficile can cause diarrhea, which can range from mild to extremely severe. In the most extreme cases, the infection can even lead to death.

Recently, a team from the London School of Hygiene and Tropical Medicine in the United Kingdom made a new and important discovery: C. difficile releases a special compound that allows it to gain ground over gut bacteria and to establish a strong presence in the gut environment. This findings are now published in the journal PLOS Pathogens.

C. difficile infections often appear after a person has followed a treatment with antibiotics, because these drugs work by essentially killing bacteria. Unfortunately, antibiotic do not only destroy the bacteria that cause harm.

Antibiotics also disrupt the balance of the gut microbiota, which contains many types of bacteria that are harmless and promote or sustain the health of the intestines. When this happens, C. difficile sometimes takes hold – and fighting it is often very complicated.

For the first time, researcher Lisa Dawson and team found that the release of para-cresol by C. difficile affects the growth of many microorganisms in the gut and allows it to prevail over other bacteria.



Working with a mouse model, the scientists observed that para-cresol targets other gut bacteria – including Escherichia coli and Klebsiella oxytoca – and prevents them from growing. These bacteria would otherwise compete with C. difficile, disrupting its expansion: however, the compound’s effect prevents them from doing so.

These findings, she suggests, may allow researchers to develop therapies that target and neutralize the mechanism that lends this bacterium some of its resilience.

My Take:
E. coli, K. oxytoca and C. difficile are all commensal bacteria. They are neither good nor bad when their numbers are contained in the gut. However, overgrowth of any commensal bacteria results in infection of the gut.

The research is interesting and may lead to new treatment(s) but we already know the cause of C. difficile infections – overuse of antibiotics. Yes, we need to find better ways to treat C. difficile but we already know how to prevent it – reduce antibiotic use in hospitals and pediatrician’s offices.

Many hospitals place all patients on antibiotic therapy regardless of their diagnosis. It’s done, just like the chest x-ray – because that’s normal operating procedure. A similar scenario plays out in the pediatrician’s office when antibiotics are commonly prescribed for the flu. Flues are viral infections, accounting for 90% of all upper respiratory infections. They do not respond to antibiotics, but C. difficile can and often does within three months of antibiotic therapy in children.

Bottom Line:
The way to avoid C. difficile is to avoid the antibiotics whenever possible. If you are diagnosed with C. difficile, request treatment with S. bolardii. It’s a yeast that should displace the C. difficile, allowing the gut microbiota to recover.

Source: September 12, 2018 NIH