* Error around 7:30: Chron's instead of Ulcerative Colitis
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This video will be in some more intestinal pathology! Here, we are going to talk about a group of diseases called inflammatory bowel disease. The two major subtypes you need to know are Chron's disease and ulcerative colitis. While no one is sure what exactly causes IBD, it appears to have an autoimmune component as well as environmental factors and bacterial factors. Whatever the case, you need to know both and how to differentiate the two.
Ulcerative colitis: this is a continuous inflammation that begins in the rectum and moves up the colon. Chron's jumps around, causing jumping injuries, but more commonly it affects the terminal ileum. This can lead to B12 deficiency and megaloblastic anemia! Because of this difference in location, UC more commonly causes bloody diarrhea, LLQ pain and can be resected to cure the disease.
The two also differ because of the nature of the inflammation. UC usually involves the mucosa and the submucosa. Chron is usually transmural. In UC, due to its superficial nature, it can affect haustra and lead to straight pipe in images, ulcers and pseudopolíps. In Chron is due to its transmural inflammation that can lead to fistulas and stenosis, as well as perianal disease.
Now just a quick oversight. There are extra-GIT manifestations of IBD. These include things like pyoderma gangrenosum, erythema nodosum, uveitis, aphthous ulcers, and ARTHRITIS. Never forget that IBD is associated with HLA-B27 arthropathies. Unique complications of UC include primary sclerosing cholangitis. The main finding of the laboratory is that it is P-ANCA positive. The only complications observed in Chron's are calcium oxalate stones.
Pharmacology includes things to suppress the immune response. This includes corticosteroids, MAB against TNF-a, antibiotics and drugs such as sulfasalazine.
Video credits to LY Med YouTube channel