Another study theorized that the human immune system traditionally evolved with the presence of parasites inside the body and that the lack thereof due to modern hygiene standards has weakened the immune system. Test subjects were reintroduced to harmless parasites, with positive responses. Microbes
It is hypothesized that maintenance of commensal microorganism growth in the GI tract is dysregulated, either as a result or cause of immune dysregulation.There is an apparent connection between Crohns disease, Mycobacterium, other pathogenic bacteria, and genetic markers. A number of studies have suggested a causal role for Mycobacterium avium subspecies paratuberculosis (MAP), which causes a similar disease, Johnes disease, in cattle. In many individuals, genetic factors predispose individuals to Mycobacterium avium subsp. paratuberculosis infection. This bacterium may produce certain compounds containing mannose, which may protect both itself and various other bacteria from phagocytosis, thereby possibly causing a variety of secondary infections.NOD2 is a gene involved in Crohns genetic susceptibility. It is associated with macrophages diminished ability to phagocytize MAP. This same gene may reduce innate and adaptive immunity in gastrointestinal tissue and impair the ability to resist infection by the MAP bacterium. Macrophages that ingest the MAP bacterium are associated with high production of TNF-α.Other studies have linked specific strains of enteroadherent E. coli to the disease.
Differential diagnosis
Other conditions with similar symptoms as Crohns disease includes intestinal tuberculosis, Behçets disease, ulcerative colitis, nonsteroidal anti-inflammatory drug enteropathy, irritable bowel syndrome and celiac disease. Irritable bowel syndrome is excluded when there are inflammatory changes. Celiac disease cannot be excluded if specific antibodies (anti-transglutaminase antibodies) are negative, nor in absence of intestinal villi atrophy. Management
There is no cure for Crohns disease and remission may not be possible or prolonged if achieved. In cases where remission is possible, relapse can be prevented and symptoms controlled with medication, lifestyle and dietary changes, changes to eating habits (eating smaller amounts more often), reduction of stress, moderate activity, and exercise. Surgery is generally contraindicated and has not been shown to prevent relapse. Adequately controlled, Crohns disease may not significantly restrict daily living. Treatment for Crohns disease involves first treating the acute problem and its symptoms, then maintaining remission of the disease. Lifestyle changes
Certain lifestyle changes can reduce symptoms, including dietary adjustments, elemental diet, proper hydration, and smoking cessation. Patients with Crohns disease are very interested in diet. Recent reviews underlined the importance to adopt diets that are best supported by evidence, even if little is known about the impact of diets on these patients. Diets that include higher levels of fiber and fruit are associated with reduced risk, while diets rich in total fats, polyunsaturated fatty acids, meat, and omega-6 fatty acids may increase the risk of Crohns. Maintaining a balanced diet with proper portion control can help manage symptoms of the disease.