Crohn’s disease is one of the most common forms of inflammatory bowel disorders.
While there are known triggers that cause the condition to flare up, the exact cause of Crohn’s disease remains unknown (1).
Sadly, there is no remedy for the disease, which can cause diarrhea, fever and fatigue, abdominal pain and cramping, bloody stool, mouth sores, reduced appetite and weight loss, and perianal disease. Instead, patients are advised to manage their symptoms as best as they can.
In Crohn’s disease, most people experience inflammation only in the last segment of the small intestine (ileum). However, it can also affect the colon (2).
While some flare-ups can be gradual, giving you time to get home to manage your symptoms, others have no warning. Worse yet, the disease may even go into periods of remission and restart without any obvious trigger.
According to estimates, around 780,000 Americans suffer from the debilitating disease (3).
Crohn’s: A Fungal Infection?
Scientists know that gut bacteria may contribute to the development of Crohn’s, but the exact mechanism is still unknown. Thankfully, a new study from Case Western Reserve University found that a fungus may also play a role in the condition (4).
In the mBio-published study, researchers used fecal samples to assess the bacteria and fungi of people with Crohn’s disease. They found that patients with Crohn’s had two bacteria present in their feces— E. coli and Serratia marcescens. Tube tests confirmed that these bacteria, along with the fungus Candida tropicalis, create a biofilm in the small intestine that triggers inflammation (5).
“The fungus is found as a colonizer in our gut. Change in the microbiota caused by a number of factors, including use of antibiotics, allow this fungus to flourish and start causing problems,” explains Mahmoud A. Ghannoum, Ph.D., professor and director of the Center for Medical Mycology at Case Western Reserve and University Hospitals Case Medical Center (6).
“We already know that bacteria, in addition to genetic and dietary factors, play a major role in causing Crohn’s disease,” he said.
“Essentially, patients with Crohn’s have abnormal immune responses to these bacteria, which inhabit the intestines of all people. While most researchers focus their investigations on these bacteria, few have examined the role of fungi, which are also present in everyone’s intestines.”
A Family Affair
The results were later compared to first-degree relatives who did not have the disease. The study included a total of 69 people from 13 families in France and Belgium.
Researchers found that the presence the bacteria and fungus were higher in people with Crohn’s than in their healthy relatives. Researchers also noted that beneficial bacteria were lower in affected patients. These results were compared with families completely unaffected by Crohn’s.
Professor Ghannoum, who led the study, said in a press release: “Among hundreds of bacterial and fungal species inhabiting the intestines, it is telling that the three we identified were so highly correlated in Crohn’s patients.”
“Furthermore, we found strong similarities in what may be called the ‘gut profiles’ of the Crohn’s-affected families, which were strikingly different from the Crohn’s-free families.”
“We have to be careful, though, and not solely attribute Crohn’s disease to the bacterial and fungal makeups of our intestines. For example, we know that family members also share diet and environment to significant degrees. Further research is needed to be even more specific in identifying precipitators and contributors of Crohn’s.”
Specialists Respond
In response to the study, Dr. Wendy Edwards, research manager at Crohn’s and Colitis UK, said: “We welcome the findings of this research which gives further evidence as to the role that fungi may play in the cause of Crohn’s disease.”
“Although the sample size of patients within this study is small, it has highlighted a potentially interesting area for further research… Crohn’s and Colitis UK are also currently funding work in this important area in order to further advance our worldwide understanding of bacteria and fungi and the role they play in Crohn’s disease.”
Dr. Jean Frederic Colombel, a gastroenterologist at The Mount Sinai Hospital in New York, also participated in the research.
He said: “Although fungi have been known to be in our bodies, this study sheds more light on the role it can play… Maybe in the future if we want to treat patients with Crohn’s disease… We should think about not only their bacteria but also the fungi,” he told Healthline.
The Future Of Crohn’s Disease Treatment
Researchers noted that this was the first time that any fungus has been linked to Crohn’s in humans, although it had been previously observed in mice. It’s also the first time that Serratia marcescens was potentially implicated in symptoms of the disease.
Since the study was conducted in a small group of patients in two European countries, critics believe that more research will be needed to see if these findings would apply to patients in other countries.
Prior to the study, Crohn’s was believed to be due to heredity and a malfunctioning immune system. This new information may lead to new treatment options for patients living with Crohn’s.