It consists of a generalized inflammation that affects the digestive tract, partially, or in all its extension. Causes gastrointestinal disorders: diarrhea, dyspepsia, gas, incontinence, pain, abdominal distension, among others. It is estimated that it can obey various causes, the most important being:

1. Genetics, genetic predisposition
2. Immunological, alteration of the immune system
3. Microbiotics, infections and alteration of the intestinal microbiota
4. Environmental, factors such as smoking, alcoholism or eating certain foods may favor it

The disease occurs for periods and then may remit and reappear indefinitely. Crohn's disease may be accompanied by other conditions such as arthritis , ankylosing spondylitis, bone disorders, skin disorders. This indicates that it should be considered as part of a more complex inflammatory systemic syndrome. It can be caused by the mycrobacterium avium.