BBC NEWS | Health | Fresh theory on cause of Crohn'sWow. A new theory, some supporting evidence, a new therapeutic direction... This doesn't happen too often. Crohn's may be another of those mysterious diseases that were once thought to be infectious, then auto-immune, and are now again considered infectious.
...The UCL team also tested Crohn's patients' response to bacteria by injecting a harmless form of E. coli under their skin.
This resulted in a huge increase in blood flow to the inflamed area in healthy volunteers - but a much smaller increase in the Crohn's patients.
The researchers found this abnormally low blood flow could be corrected by treatment with Viagra.
The researchers believe that, because Crohn's patients have weakened immune systems, they are unable to destroy bacteria that penetrate the intestinal wall.
Thus the bacteria are left to build up in the tissue, stimulating the secretion of inflammatory chemicals that trigger the symptoms of Crohn's...
Will ulcerative colitis turn out to have an utterly unrelated mechanism? And what does this do to one of my favorite research programs -- using worms to treat inflammatory bowel disease?
Keeping fingers crossed ...