New and very interesting research that comes out of Sweden shows that there is an association between Crohns and a viral strain known as enterovirus.
Research has discovered that a group of children that has Crohn's disease also have a virus in their intestines. This virus is known as enterovirus.
This is the first time that a link has been discovered between IBD (inflammatory bowel disease) and enteroviruses, which are a genus of positive-sense single-stranded RNA viruses. These finding were published in the international journal Clinical and Translational Gastroenterology
Alkwin Wanders,who is one of the authors of the study at Uppsala University Hospital & Uppsala University, believes that the results could help better understand the root causes of Crohn's disease.
Not much is known about what causes Crohn's disease; there have been over 140 gene mutations associated with condition. Most of the genes that have been identified play a role in immune defense
There have been many theories suggesting that the condition could be caused by a lack of immune defense against various different pathogens, which would mean that Crohn's disease is a result of both genetic factors & environmental factors.
Researchers at McGill University and Génome Québec Innovation Centre, along with scientists from other Canadian and Belgian institutions, discovered there are DNA variations in a gene that increase susceptibility to developing Crohn's disease. Their finding was published in Nature Genetics.
Crohn's diseases is characterized by inflammation of the digestive tract, affecting different parts of the gut, from the mouth down to the anus. Symptoms include: weight loss, strictures in the intestines diarrhea and severe stomach ache.
The genes associated with the onset of the condition are vital for the immune defense against a certain type of RNA virus.
A research team in Sweden set out to determine whether this type of virus might be linked to a higher risk of developing Crohn's disease. They wanted to see whether a group of patients with Crohn's disease had RNA viruses. They focused particularly on a group of RNA viruses called enteroviruses - which infect the intestinal mucous lining. What they found was that children suffering from Crohn's disease had significantly higher numbers of enteroviruses in their intestines compared to those in the control group - without Crohn's disease.
The scientists also identified enteroviruses in nerve cell ganglia (in deeper parts of the intestinal wall). In addition, receptors for a group of enteroviruses were found in the intestinal mucous linings and nerve cell ganglia, which gives insight into how the virus enters the system of nerves in the intestine.
They also found that enteroviruses are also stored in nerve cells in the intestine and then spread via nerve fibers to other parts of the intestine.
Alkwin Wanders, said that this would explain the periodic nature of the disease.
The study included a total of nine children with advanced Crohn's disease as well as fifteen with incipient symptoms of the disease. The investigators said that there needs to be further research conducted on a larger group of patients to fully understand the link.
The authors said the results from this study "show, for the first time, significant presence of HEV-B in the mucosa and enteric nervous system of patients with ileocecal Crohn's disease (ICD)."
They concluded: Our data should be put in perspective of what others have found and discussed in terms of a role of interplay between mutations in genes encoding proteins involved in innate viral immunity and autophagy, and the presence of microorganisms, both viruses and bacteria, as a triggering factor of Crohn's disease."
Written by Joseph Nordqvist
18 July 2013