0:00 So, this video we're going to look at IBD, which is inflammatory bowel disease, 0:10 a chronic 0:10 inflammatory bowel disease which pursue a protracted, relapsing, and remitting 0:16 course. 0:17 There are two types of IBDs, and let us look at them now. 0:22 So, IBD typically involve the colon, but of course, one of the types of IBD 0:30 involve 0:31 the whole GIT. 0:34 Now the two types of IBD are ulcerative colitis and Crohn's disease. 0:41 When talking about ulcerative colitis, it mainly presents with inflammation of 0:46 the rectal 0:47 and sigmoid colon, about 40 to 50 percent, and this is referred to as proctitis 1:00 . 1:01 Now comparing that to Crohn's disease, in Crohn's disease, the main area 1:06 affected is 1:07 the cecum and the ileum, the ileo-cecal area. 1:11 40% of Crohn's cases involve the ileo and ileo-colonic area. 1:19 The second most common area affecting Crohn's is the small intestine, about 30 1:25 to 40 percent 1:26 of cases, and in the small intestine, we see the inflammation in segments. 1:32 This is termed skip lesions because you have inflammation and then you have no 1:39 inflammation 1:40 and then you have inflammation again, and then no inflammation, etc. 1:45 Some people who have Crohn's can have skip lesions in the colon, the large 1:51 intestine. 1:51 20% of Crohn's disease cases have this, and this is referred to as Crohn's col 1:57 itis. 1:58 And finally, a small majority of cases have perineal inflammation. 2:04 So those were the four most common areas affected in Crohn's disease. 2:12 And as we have learned, a typical characteristic of Crohn's disease are the 2:18 skip lesions. 2:20 Going back to all sort of colitis, the main areas affected as we talked about 2:26 is the rectal 2:27 sigmoid area, and this is termed proctitis. 2:31 Well, a characteristic of all sort of colitis is that the inflammation can 2:37 spread and it 2:38 spreads approximately. 2:41 So from the rectal sigmoid area up the descending colon, 30 to 40 percent of 2:47 all sort of colitis 2:48 cases have this, and this is termed left-sided colitis. 2:54 If the inflammation spread far enough that it reaches the transverse colon, 2:58 this is known 2:59 as extensive colitis. 3:02 So we just saw the common areas affected in all sort of colitis and Crohn's 3:07 disease. 3:08 And we saw that they had some differences in that all sort of colitis spreads 3:13 distal 3:13 to proximal, and Crohn's disease have skip lesions and mainly affects the ile 3:18 osteical 3:19 area. 3:22 But there are a lot more differences which we will go over later on. 3:26 But first, let us look at the signs and symptoms associated with the 3:30 inflammatory bowel disease. 3:33 So signs and symptoms of inflammatory bowel disease can include, but not always 3:38 , diarrhea, 3:39 rectal bleeding, abdominal pain, tenesmus, fever, weight loss, vomiting, cramps 3:46 , and 3:46 muscle spasms. 3:49 This looks more at the differences now and similarities between the two types 3:54 of inflammatory 3:56 bowel disease. 3:59 So we will look at the differences in gender, incidents, smoking, association, 4:06 the onset, 4:07 location, pathology, histological differences, as well as complications. 4:14 So in ulcerative colitis, both genders are affected in the same ratio, whereas 4:20 in Crohn's 4:21 they affect more female than male. 4:25 Incidents of ulcerative colitis and Crohn's disease are similar, except there 4:28 are more 4:29 cases of Crohn's disease diagnosed per year, 2.1 to 20 per 100,000. 4:38 Smoking is very interesting for inflammatory bowel disease, because for ulcer 4:43 ative colitis, 4:44 smoking is actually a protective factor, whereas if you smoke in Crohn's this 4:49 actually 4:50 aggravates the condition. 4:53 The onset of ulcerative colitis and Crohn's are roughly the same. 4:58 The location which we talked about earlier for ulcerative colitis is mainly the 5:03 distal 5:03 colon, the rectum and sycamoid area, remember? 5:08 And for Crohn's it's the distal ilium and sycam, but it can also affect other 5:14 areas 5:14 along the GIT. 5:17 Now let's talk about the pathology, the differences. 5:20 So for ulcerative colitis, it is a continuous inflammatory lesion that 5:26 basically progresses 5:28 from the distal colon to the proximal colon. 5:33 Now whereas in Crohn's it is typically discontinuous, patchy, gut inflammation 5:39 with skip lesions. 5:42 Histologically ulcerative colitis is a superficial inflammation, whereas Crohn 5:46 's disease is 5:46 a transmural inflammation, which means that it actually goes through all the 5:52 layers of 5:52 the colon. 5:56 Complications of ulcerative colitis include severe bleeding, toxic make a colon 6:00 , rupture 6:00 of bowel as well as colon cancer. 6:03 For Crohn's disease, complications is more severe, because histologically it 6:09 affects 6:09 all the layers of the GIT, transmural inflammation. 6:13 So therefore, complications include stenosis, abcess formation, fistula, colon 6:18 cancer as 6:18 well as perforation. 6:20 Okay, now let's put all this into drawing. 6:25 Let us first zoom into the ulcerative colitis affected colon here. 6:30 So here is the inflammation of the large intestine. 6:33 The superficial inflammation, remember. 6:38 Ulcerative colitis, it changes as in relapsing and remitting. 6:43 When the disease is active, it causes ulceration and inflammation. 6:48 When inactive, the cells are basically dying. 6:52 You get atrophy of cells following the inflammatory reaction. 7:00 In ulcerative colitis, you can get complications such as severe bleeding, toxic 7:05 make a colon, 7:05 rupture of the bowel and colon cancer. 7:10 Now if we were to take a section of the large intestine, we have the hist 7:15 ological layers, 7:16 of course, the musculitis, the submucosa, the mucosa, and you can also have 7:22 these things 7:22 called pseudopolyps, which is a characteristic feature of ulcerative colitis. 7:28 Psychopolyps arise because the cells of the colon are trying to regenerate, but 7:34 they regenerate 7:36 weirdly causing these polyps as a result. 7:40 Now let us compare ulcerative colitis to Crohn's disease. 7:43 In Crohn's disease, it can affect the large intestine or the small intestine. 7:49 Let us zoom into the small intestine. 7:52 So here within the small intestine, you see trans-mural inflammation with skip 7:56 lesions. 7:57 Complications of Crohn's disease include stenosis, abscess formation, fistula, 8:03 colon 8:03 cancer, as well as granulomas. 8:06 If we were to take a cross section of the small intestine, here is the mesentry 8:11 , the 8:12 musculares, the submucosa, and the mucosa. 8:17 We can see in Crohn's disease that all the layers are affected, it is a trans-m 8:23 ural inflammation. 8:24 And so complications of Crohn's disease can be quite serious in that it can 8:28 lead to perforation, 8:30 fistula, etc. 8:35 And in the next video, we will look more actually at the pathophysiology of 8:39 inflammatory 8:40 bowel disease, as well as look at the complications, the local as well as 8:46 systemic, and the investigations 8:48 and management that is performed for inflammatory bowel disease. 8:53 Thank you.
