Crohns and colitis

Crohn's disease and colitis are often referred to together as inflammatory bowel disease (IBD.) Crohns is a chronic inflammatory disease of the intestines. It can affect the digestive system from mouth to the anus, and can causes breaks within the linings of both the small and large intestine. Whereas ulcerative colitis only typically affects the colon (large intestine) and inflammation caused by Crohns may be in patches, whereas inflammation due to ulcerative colitis is continuous.

Crohn’s disease is a non-contagious disease but the cause of it is unknown although it is suspected to be due to a bacterial infection and can be genetically inherited.  Within a patient with IBS the immune system is chronically activated by any molecules, not just harmful such as bacteria, viruses and fungi. It is this continued abnormal activation which results in chronic inflammation and ulceration. The gene NOD2 is thought to be responsible for the abnormal activation of the immune system; it is this gene which can be inherited. The symptoms and severity vary among patients and symptoms can fluctuate in periods of remission (inactivity) and relapse (activity.)  Symptoms include abdominal pain, diarrhea and rectal bleeding. In crohn’s disease pain is commonly experienced in the lower right abdomen and in colitis the lower left of the abdomen.

Neither Crohns nor Colitis has a cure, but there is medication available to induce remissions and maintain them whilst reducing side effects. Anti-inflammatory agents such as corticosteroids and antibiotics are often used. With most of the drugs there a negative side effects, such as with corticosteroids there is increased risk of acne, weight gain, cataracts, depression and high blood pressure. The biggest side effect with corticosteroids is aseptic necrosis; this is a condition in which there is death and degeneration of the hipbone.  Sometimes surgery is used as treatment to divert digestive waste away from the inflamed colon, such as a ileostomy; during this operation the ileum is disconnected from the colon and re-routed through a hole made in the abdomen, through which an external bag is attached to collect waste products. Usually after several months when the colon has recovered, the stoma (gap in abdomen) is closed and the ileum reattached to the colon.

References:

http://www.medicinenet.com/crohns_disease/article.htm
http://www.nhs.uk/Conditions/Crohns-disease/Pages/Treatment.aspx
http://www.nhs.uk/Conditions/Crohns-disease/Pages/Treatment.aspx
http://www.columbia-stmarys.org/Crohn_vs_Ulcerative_Colitis