Inflammatory bowel disease inflammatory changes. Crohn's can affect any part of the gastrointestinal tract, from mouth to anus ("skip lesions"), although a majority of the cases start in the terminal ileum. Ulcerative colitis, in contrast, is restricted to the colon and the rectum. Microscopically, ulcerative colitis is restricted to the mucosa (epithelial lining of the gut), while Crohn's disease affects the full thickness of the bowel wall ("transmural lesions"). Lastly, Crohn's disease and ulcerative colitis present with extra-intestinal manifestations (such as liver problems, arthritis, skin manifestations and eye problems) in different proportions. In 10–15% of cases, a definitive diagnosis neither of Crohn's disease
Oral manifestations of systemic disease Oral manifestations of systemic disease Oral manifestations of systematic disease are signs and symptoms of disease occurring elsewhere in the body detected in the oral cavity and oral secretions. High blood sugar can be detected by sampling saliva. Saliva sampling may be a non-invasive way to detect changes in the gut microbiome and changes in systemic disease. The association between the salivary microbiome and with Polycystic Ovarian Syndrome has been characterized. "[S]aliva microbiome profiles correlate with those in the stool, despite the fact that the bacterial communities in the two locations differ greatly. Therefore, saliva may be a useful alternative