Gastric Disorders の全文書き起こし

of acute gastritis. 21 00:01:50,760.31664921 --> 00:01:55,900.31664921 Patients would usually present with sudden epigastric pain, nausea, vomiting, and possible hematomasis. 22 00:01:56,220.31664921 --> 00:01:59,810.31664921 Their endoscopy would show reddish mucosa with small superficial erosions. 23 00:02:00,170.31664921 --> 00:02:05,70.31664921 And if we perform biopsy, we would find neutrophilic infiltrates above the basement membrane. 24 00:02:05,675.31664921 --> 00:02:10,795.31664921 Okay, so what do you do then? Just cut out the alcohol and the NSAIDs? Well, yeah, pretty much. 25 00:02:11,125.31664921 --> 00:02:13,415.31664921 Stopping NSAIDs and alcohol is actually the first step. 26 00:02:13,655.31664921 --> 00:02:18,115.31664921 But you can also use proton pump inhibitors, or PPIs, to reduce acid and promote healing. 27 00:02:18,505.31564921 --> 00:02:22,265.31664921 And luckily, the prognosis is usually good if the offending agents are removed. 28 00:02:22,685.31664921 --> 00:02:34,722.55227147 All right, quiz time! Which histological finding is most characteristic of acute gastritis? The answer is neutrophilic infiltrate above the basement membrane. 29 00:02:34,922.55327147 --> 00:02:37,742.55327147 That's the hallmark of acute inflammation in gastritis. 30 00:02:38,677.55327147 --> 00:02:42,87.55327147 Our next case is a six year old man in the ICU with severe burns. 31 00:02:42,257.55327147 --> 00:02:49,57.55327147 He suddenly starts vomiting blood and his endoscopy shows multiple small ulcers in the stomach and duodenum, less than one centimeter in diameter. 32 00:02:49,607.55327147 --> 00:02:50,277.55327147 Yikes. 33 00:02:50,327.55327147 --> 00:02:52,677.55327147 Vomiting blood? That's terrifying. 34 00:02:52,927.55327147 --> 00:02:55,817.55327147 What's happening here? Yep, that's definitely a red flag. 35 00:02:56,17.55327147 --> 00:03:04,757.55327147 This is a case of stress ulcers, which are basically acute mucosal lesions that develop rapidly in critically ill patients due to severe stress, trauma, or shock. 36 00:03:05,77.55327147 --> 00:03:07,37.55327147 And we actually have two types of stress ulcers. 37 00:03:07,417.55327147 --> 00:03:09,77.55327147 The first type is curling's ulcers. 38 00:03:09,327.55327147 --> 00:03:14,927.55327147 They're usually found in the proximal duodenum and commonly occur in patients with severe burns, which is what we see in our patient here. 39 00:03:15,577.55327147 --> 00:03:17,447.55327147 The second type is Cushing's ulcers. 40 00:03:17,617.55327147 --> 00:03:22,707.55227147 These can appear in the stomach, duodenum, or esophagus and are linked to increased intracranial pressure. 41 00:03:23,267.55327147 --> 00:03:27,317.55327147 So it's like the stomach's throwing a fit because the body's under extreme stress. 42 00:03:27,687.55327147 --> 00:03:28,327.55327147 Exactly. 43 00:03:28,477.55227147 --> 00:03:31,67.55327147 The body's stress response can really throw things out of whack. 44 00:03:31,227.55327147 --> 00:03:38,357.55327147 Okay, so what's the reason behind these ulcers? Is it just too much acid? It actually depends on the type of stress ulcer. 45 00:03:38,697.55327147 --> 00:03:44,57.55327147 So for curling's ulcers, the severe burns cause hypovolemia and ischemia to the gastric mucosa. 46 00:03:44,447.55327147 --> 00:03:48,897.55327147 So you basically reduce blood flow to the stomach to the point that it impairs the protective barrier. 47 00:03:49,427.55227147 --> 00:03:53,47.55327147 However, for Cushing's ulcers, it's all about increased intracranial pressure. 48 00:03:53,477.55327147 --> 00:03:55,297.45327147 That high pressure triggers the vagus nerve. 49 00:03:55,447.55327147 --> 00:03:57,817.55327147 and causes a surge in gastric acid secretion. 50 00:03:58,147.55327147 --> 00:04:02,17.55327147 Because if you remember, the vagus nerve is a triggering factor for stomach acid release. 51 00:04:02,397.55327147 --> 00:04:04,887.55327147 All of this leads to acute ulceration of the mucosa. 52 00:04:05,567.55327147 --> 00:04:12,757.55327147 Aha, so curling's ulcers are due to the lack of blood flow, while cushing ulcers are more about too much acid. 53 00:04:12,827.55327147 --> 00:04:16,517.55327147 Exactly, two different roads to the same destination, ulcers. 54 00:04:17,247.55327147 --> 00:04:27,132.55327147 All right, so if a doctor suspects stress ulcers, What kind of clues are they looking for? The typical picture of curling's ulcers is a burn patient with hematemesis or melanoma. 55 00:04:27,672.55327147 --> 00:04:32,422.55227147 Think of getting burned by a curling iron to remember burns as a cause for curling's ulcers. 56 00:04:32,962.55327147 --> 00:04:39,802.55327147 As for Cushing's ulcers, it'll likely be a patient with a history of head trauma or neurosurgery who suddenly gets upper GI bleeding. 57 00:04:40,212.55327147 --> 00:04:42,862.55327147 A nice way to remember this is always cushion the brain. 58 00:04:43,752.55327147 --> 00:04:45,432.55327147 Okay, I like that. 59 00:04:45,472.55327147 --> 00:04:47,862.55327147 I don't think I'll ever confuse those two again. 60 00:04:48,212.55327147 --> 00:04:53,302.55227147 So what about more specific tests like endoscopy? Oh yeah, I was just getting to that. 61 00:04:53,432.55327147 --> 00:05:02,432.55327147 An endoscopy is used to further narrow down the diagnosis, where we can see multiple, small, round ulcers less than one centimeter in diameter with sharply demarcated edges. 62 00:05:02,802.55327147 --> 00:05:06,122.55327147 And these are often seen in different locations based on which type of ulcer it is. 63 00:05:06,537.55327147 --> 00:05:13,207.55327147 Remember, curling's ulcers are usually found in the proximal duodenum, while Cushing's ulcers can appear in the stomach duodenum or even the esophagus. 64 00:05:13,637.55327147 --> 00:05:21,437.55327147 And something important to remember is that these are

acute ulcers, so you would not see any scarring or fibrosis, and that's how you would know they're not chronic ulcers. 65 00:05:21,877.55327147 --> 00:05:22,737.55327147 Got it, got it. 66 00:05:22,747.55327147 --> 00:05:27,927.55327147 So the patient's history plus what we see on endoscopy really helps narrow it down. 67 00:05:28,7.55327147 --> 00:05:29,147.55327147 Exactly, you got it. 68 00:05:29,277.55327147 --> 00:05:32,697.55327147 And the absence of scarring is a big clue that these are acute, not chronic. 69 00:05:33,237.55327147 --> 00:05:41,577.55227147 Okay, so how do we treat these stress ulcers? Can they heal on their own or do you actually need to step in fast? You definitely need to step in. 70 00:05:41,907.55327147 --> 00:05:42,817.55327147 And here's what you do. 71 00:05:43,197.55327147 --> 00:05:49,417.55327147 First, you need to manage the underlying cause, whether that is shock, sepsis, trauma, or increased intracranial pressure. 72 00:05:49,927.55327147 --> 00:05:55,177.55327147 Then you go in with your classic PPI's or H2 blockers to reduce acid production and promote healing. 73 00:05:55,827.55327147 --> 00:06:02,77.55327147 Sometimes, in severe cases, you may need to intervene with endoscopic hemostasis or even surgery to fix any complications. 74 00:06:02,597.55327147 --> 00:06:06,457.55327147 Luckily, though, the prognosis is generally good if the underlying cause is treated quickly. 75 00:06:06,687.55327147 --> 00:06:08,957.55327147 Aha, so it is a race against time. 76 00:06:09,257.55327147 --> 00:06:12,47.55327147 Fix the underlying issue and calm the stomach down. 77 00:06:12,177.55227147 --> 00:06:13,117.55227147 Yep, exactly. 78 00:06:13,207.55327147 --> 00:06:14,927.55327147 The quicker you act, the better the outcome. 79 00:06:15,257.55327147 --> 00:06:25,929.62684111 Alright, quiz time! Which condition is the most commonly associated with Cushing's ulcers? The answer is intracranial injury. 80 00:06:26,179.72684111 --> 00:06:30,109.72684111 Cushing's ulcers are all about the vagal stimulation from increased intracranial pressure. 81 00:06:30,379.72684111 --> 00:06:32,499.72684111 Remember, you always cushion the brain. 82 00:06:33,139.72684111 --> 00:06:34,359.72684111 Yeah, right, right, right. 83 00:06:34,409.72584111 --> 00:06:36,69.72684111 Always cushion the brain. 84 00:06:36,79.72684111 --> 00:06:37,659.72684111 That really is a great mnemonic. 85 00:06:38,379.72684111 --> 00:06:39,749.72684111 Now, on to our next case. 86 00:06:40,509.72684111 --> 00:06:44,909.72684111 A 63 year old woman presents with fatigue, glossitis, and tingling in her hands and feet. 87 00:06:45,339.72684111 --> 00:06:48,609.72684111 Blood tests show megaloblastic anemia and low B12 levels. 88 00:06:48,949.72684111 --> 00:06:50,529.72684111 She has a history of thyroiditis. 89 00:06:50,659.72684111 --> 00:06:54,409.72684111 Her endoscopy reveals atrophic mucosa in the gastric body and fundus. 90 00:06:55,9.72684111 --> 00:07:02,989.72684111 Fatigue, a sore tongue, and tingling? And with a history of thyroiditis, it seems like there's more to the story, huh? Absolutely. 91 00:07:03,89.72684111 --> 00:07:05,389.72684111 This woman likely has autoimmune gastritis. 92 00:07:05,719.72684111 --> 00:07:11,639.72684111 It's a type of chronic gastritis that involves the autoimmune destruction of the gastric parietal cells and sometimes intrinsic factor. 93 00:07:12,109.72684111 --> 00:07:17,979.72684111 It primarily affects the body and fundus of the stomach, leading to atrophy, achlorhydria, and B12 deficiency. 94 00:07:18,399.72684111 --> 00:07:21,949.72684111 Okay, so her own immune system's causing the damage. 95 00:07:21,959.72684111 --> 00:07:22,779.72684111 Yep, you got it. 96 00:07:23,129.72684111 --> 00:07:23,879.72684111 Gotcha, gotcha. 97 00:07:24,389.72684111 --> 00:07:32,284.72684111 Okay, so what's the actual mechanism here? And how does the immune system end up causing this B12 deficiency? Well, it all comes down to autoantibodies. 98 00:07:33,284.72684111 --> 00:07:35,704.72684111 First, we have the anti intrinsic factor antibodies. 99 00:07:36,24.72684111 --> 00:07:42,464.72684111 These prevent the absorption of B12 in the terminal ileum, causing B12 deficiency and eventually megaloblastic anemia. 100 00:07:43,14.72584111 --> 00:07:45,434.72684111 Then, you have the antiparietal cell antibodies. 101 00:07:45,664.72684111 --> 00:07:48,224.72584111 And from their name, you know that they destroy parietal cells. 102 00:07:48,534.72684111 --> 00:07:51,324.72684111 So now the stomach cannot make acid, and you get achlorhydria. 103 00:07:51,784.72684111 --> 00:07:58,314.72684111 This destruction of the parietal cells causes G cells in the antrum to go crazy with gastrin secretion in an attempt to compensate. 104 00:07:58,734.72684111 --> 00:08:00,904.72684111 And that's how you get hypergastronemia. 105 00:08:01,484.72684111 --> 00:08:05,964.72684111 Over time, these G cells undergo hyperplasia and may lead to carcinoid tumors. 106 00:08:06,354.72584111 --> 00:08:08,464.72684111 Wow, so it is like a domino effect. 107 00:08:08,464.72684111 --> 00:08:14,84.72684111 You destroy the parietal cells, lose acid and intrinsic factor, then you don't have B12 anymore. 108 00:08:14,254.72684111 --> 00:08:14,954.72684111 Exactly. 109 00:08:15,24.72684111 --> 00:08:16,914.72584111 And that leads to the symptoms we're seeing. 110 00:08:17,359.72684111 --> 00:08:27,739.72684111 Alright, so if a doctor suspects autoimmune gastritis, what kind of clues should they be looking for? Well, first of all, the patient would present with symptoms of B12 deficiency. 111 00:08:27,739.72684111 --> 00:08:32,879.72684111 So think of fatigue, tingling in the hands and feet, ataxia, and a smooth, beefy red tongue. 112 00:08:33,359.72684111 --> 00:08:41,499.72584111 Then when you look at their lab results, you would see macrocytic anemia, low

B12 levels, high gastrin levels, and of course, positive antiparietal cell antibodies. 113 00:08:41,789.72584111 --> 00:08:50,399.72684111 Okay, and what about their endoscopy? On endoscopy, you would find atrophic mucosa with loss of rugal folds, specifically in the body and fundus of the stomach. 114 00:08:50,759.72684111 --> 00:08:56,903.06017444 And then if you take a biopsy, you would see a lymphocytic infiltrate, intestinal metaplasia, and loss of parietal cells. 115 00:08:57,423.05917444 --> 00:08:58,113.06017444 Got it, got it. 116 00:08:58,423.05917444 --> 00:09:00,223.06017444 So it's a whole collection of clues. 117 00:09:00,253.05917444 --> 00:09:02,393.06017444 Low B12, high gastrin. 118 00:09:02,623.06017444 --> 00:09:05,593.06017444 Positive antibodies and a biopsy confirming it. 119 00:09:05,763.06017444 --> 00:09:08,433.06017444 Yep, it's like piecing together all the puzzle pieces. 120 00:09:09,133.06017444 --> 00:09:17,303.06017444 Okay, so once they figure out it is autoimmune gastritis, how do they treat it? Are we talking lifelong meds? Pretty much, yeah. 121 00:09:17,463.06017444 --> 00:09:21,313.06017444 It's very important for these patients to take B12 supplements for the rest of their lives. 122 00:09:21,633.06017444 --> 00:09:27,153.06017444 They should also regularly monitor for gastric adenocarcinoma and carcinoid tumors because they are at a higher risk. 123 00:09:27,493.05917444 --> 00:09:33,483.06017444 Luckily, their prognosis is good if they maintain their B12, but unfortunately, they're still at risk of gastric cancer. 124 00:09:33,883.06017444 --> 00:09:38,503.06017444 Uh huh, so it is all about managing the damage and keeping an eye out for any bigger threats. 125 00:09:38,543.06017444 --> 00:09:39,433.06017444 Yep, you got it. 126 00:09:40,23.06017444 --> 00:09:51,383.05917444 Okay, Raghda, do you want to guess what time it is? Quiz time! You got it! Now, which of the following laboratory findings is the most characteristic of autoimmune gastritis? A. 127 00:09:51,563.05917444 --> 00:09:53,583.06017444 Low gastrin levels B. 128 00:09:53,763.06017444 --> 00:09:58,343.06017444 High gastrin levels and positive antiparietal cell antibodies C. 129 00:09:58,583.06017444 --> 00:10:00,793.06017444 Hyperchlorhydria or D. 130 00:10:01,33.06017444 --> 00:10:06,935.32149416 High B12 levels The answer is B. 131 00:10:07,105.32149416 --> 00:10:10,355.32149416 High gastrin levels and positive antiparietal cell antibodies. 132 00:10:10,605.32149416 --> 00:10:13,335.32149416 Those are the key markers for autoimmune gastritis. 133 00:10:13,625.32049416 --> 00:10:14,755.32049416 Nice, you got it. 134 00:10:15,25.32149416 --> 00:10:16,385.32149416 Let's go to the next case. 135 00:10:17,526.36484254 --> 00:10:22,216.36484254 Okay, a 50 year old male presents with burning epigastric pain that worsens after meals. 136 00:10:22,346.36484254 --> 00:10:24,466.36484254 And he says he's been experiencing this for months. 137 00:10:24,816.36484254 --> 00:10:28,136.36484254 There's no vomiting or weight loss, and a urea breath test is positive for H. 138 00:10:28,146.36484254 --> 00:10:28,666.36484254 pylori. 139 00:10:28,956.36384254 --> 00:10:32,26.36484254 An endoscopy shows erythematous mucosa in the antrum. 140 00:10:32,611.36484254 --> 00:10:34,541.36484254 Aha, so it is something to do with H. 141 00:10:34,561.36484254 --> 00:10:36,581.36484254 pylori, isn't it? Spot on. 142 00:10:36,721.36484254 --> 00:10:37,791.36484254 This patient has H. 143 00:10:37,801.36484254 --> 00:10:39,861.36484254 pylori associated chronic gastritis. 144 00:10:40,241.36484254 --> 00:10:46,411.36484254 This is actually the most common type of chronic gastritis worldwide, and it usually starts in the antrum but can progress to the whole stomach. 145 00:10:46,801.36384254 --> 00:10:49,281.36384254 Eventually, it leads to atrophy and intestinal metaplasia. 146 00:10:49,716.36484254 --> 00:10:53,526.36484254 with an increased risk of ulcers, mouth lymphoma, and adenocarcinoma. 147 00:10:54,6.36484254 --> 00:10:55,766.36484254 Alright, so what makes H. 148 00:10:55,796.36484254 --> 00:10:58,296.36484254 pylori such a troublemaker? H. 149 00:10:58,306.36484254 --> 00:11:00,886.36484254 pylori shows up, makes a whole mess, and doesn't leave. 150 00:11:01,26.36384254 --> 00:11:06,66.36384254 It uses urease to convert urea into ammonia, which neutralizes stomach acid, allowing it to survive. 151 00:11:06,483.0315092 --> 00:11:14,593.0315092 But that's not all! It also releases cytotoxins such as CAG A that cause chronic inflammation and mucosal damage, leading to atrophy and intestinal metaplasia. 152 00:11:15,103.0315092 --> 00:11:15,763.0315092 Patients with H. 153 00:11:15,793.0315092 --> 00:11:20,673.0315092 pylori infection are at risk of peptic ulcers due to increased gastrin secretion and acid production. 154 00:11:20,893.0315092 --> 00:11:26,313.0315092 And unfortunately, long term infection can lead to malt lymphoma by promoting lymphoid tissue hyperplasia. 155 00:11:27,48.0315092 --> 00:11:30,38.0315092 Wow, so it's not just crashing the party. 156 00:11:30,48.0315092 --> 00:11:32,88.0315092 It's trashing the whole house. 157 00:11:32,548.0315092 --> 00:11:41,378.0315092 It's got urease, allowing it to survive, and cytotoxins, damaging the mucosa, both increasing the risk of peptic ulcers and cancer. 158 00:11:41,773.0315092 --> 00:11:42,513.0315092 Exactly. 159 00:11:42,583.0315092 --> 00:11:44,853.0315092 That's why it's so dangerous if left untreated. 160 00:11:45,173.0315092 --> 00:11:45,563.0315092 Right. 161 00:11:45,663.0315092 --> 00:11:54,713.0315092 And how do doctors spot these patients? Well, they present with burning epigastric pain and tenderness that worsens with meals, nausea, and sometimes bloating. 162 00:11:55,43.0315092 --> 00:11:59,493.0305092 Their endoscopy would show an erythematous specifically in the antrum. 163

00:11:59,993.0315092 --> 00:12:05,323.0315092 On biopsy, you would see neutrophilic infiltrate, lymphoid aggregates, and most importantly, H. 164 00:12:05,353.0315092 --> 00:12:07,413.0315092 pylori visible with special stains. 165 00:12:07,718.0315092 --> 00:12:14,908.0315092 But since endoscopy and biopsy are too invasive, these patients are usually just diagnosed with a positive urea breath test or stool antigen test. 166 00:12:15,198.0315092 --> 00:12:16,688.0315092 We can also detect anti H. 167 00:12:16,718.0315092 --> 00:12:21,288.0315092 pylori IgG antibodies on serology, but this method is not useful for active infection. 168 00:12:21,778.0315092 --> 00:12:22,328.0315092 Got it. 169 00:12:22,348.0315092 --> 00:12:26,518.0315092 So urea breath test or stool antigen test for the diagnosis. 170 00:12:27,78.0315092 --> 00:12:28,698.0315092 And how do you get rid of H. 171 00:12:28,718.0315092 --> 00:12:33,908.0315092 pylori? Do you need to go for antibiotics? Yes, you need to use antibiotics, but not alone. 172 00:12:34,268.0305092 --> 00:12:36,348.0315092 The go to is something called triple therapy. 173 00:12:36,628.0315092 --> 00:12:41,838.0315092 which is made up of PPI plus clarithromycin plus amoxicillin for 10 to 14 days. 174 00:12:42,288.0315092 --> 00:12:43,298.0315092 But sometimes, if the H. 175 00:12:43,308.0315092 --> 00:12:51,788.0315092 pylori is found to be resistant to clarithromycin, you would need to go for quadruple therapy, which involves bismuth, metronidazole, tetracycline, and a PPI. 176 00:12:52,133.0315092 --> 00:12:56,673.0315092 After that, you need to follow up with your patient four weeks after stopping therapy to confirm eradication. 177 00:12:57,23.0315092 --> 00:12:59,993.0315092 That sounds like an intense therapy regimen. 178 00:13:00,333.0315092 --> 00:13:03,813.0315092 Do they usually respond well? Well, luckily, yes. 179 00:13:04,3.0315092 --> 00:13:06,463.0315092 If treated early, these patients have a good prognosis. 180 00:13:06,743.0315092 --> 00:13:12,133.0315092 But the main issue comes when they're left untreated because that increases the risk of ulcers and gastric cancer. 181 00:13:12,933.0315092 --> 00:13:15,893.0315092 Okay, so the sooner you get rid of it, the better. 182 00:13:16,293.0315092 --> 00:13:19,253.0315092 Now, let's go for a practice question. 183 00:13:19,653.0315092 --> 00:13:22,933.0315092 Which complication is most commonly associated with H. 184 00:13:22,963.0315092 --> 00:13:29,83.7528149 pylori infection? The answer is malt lymphoma. 185 00:13:29,453.7528149 --> 00:13:30,143.7528149 Long term H. 186 00:13:30,153.7528149 --> 00:13:36,173.6528149 pylori infection increases the risk of malt lymphoma due to chronic inflammation and lymphoid hyperplasia. 187 00:13:37,427.86653878 --> 00:13:38,527.86653878 Now, on to our next case. 188 00:13:38,677.86653878 --> 00:13:46,197.86653878 Here we have a 48 year old man who presents with burning epigastric pain

that gets worse 2 3 hours after eating, and often wakes him up at night. 189 00:13:46,717.86653878 --> 00:13:49,137.86653878 The pain is temporarily relieved by antacids. 190 00:13:49,417.86653878 --> 00:13:52,207.86653878 He admits to taking NSAIDs regularly for chronic back pain. 191 00:13:52,617.86653878 --> 00:13:54,397.86653878 He does not have weight loss or vomiting. 192 00:13:54,787.86653878 --> 00:13:58,277.86653878 Endoscopy reveals a single ulcer on the anterior wall of the duodenum. 193 00:13:59,47.86653878 --> 00:14:02,777.86653878 Oof, being woken up by stomach pain sounds awful. 194 00:14:03,67.86653878 --> 00:14:05,887.86653878 What's your take on this one? Yeah, it's definitely not fun. 195 00:14:06,237.86653878 --> 00:14:08,607.86653878 This patient has peptic ulcer disease, or PUD. 196 00:14:09,87.86653878 --> 00:14:11,777.86553878 It's characterized by deep focal defects in the mucosa. 197 00:14:12,207.86653878 --> 00:14:16,217.86553878 PUD actually has two main types of ulcers, and those are either gastric or duodenal. 198 00:14:16,737.86553878 --> 00:14:22,647.86653878 Duodenal ulcers are more common and are usually benign, while gastric ulcers are less common and have a higher risk of being malignant. 199 00:14:22,827.86653878 --> 00:14:28,47.86653878 Got it, so duodenal ulcers are more common and more benign than gastric ulcers. 200 00:14:28,272.86653878 --> 00:14:29,2.86653878 Exactly. 201 00:14:29,152.86653878 --> 00:14:31,702.86653878 That's why gastric ulcers may sometimes need a closer look. 202 00:14:32,22.86653878 --> 00:14:39,922.86653878 Okay, and what's causing these ulcers? Is it too much acid, not enough protection, or both? Both, actually. 203 00:14:40,62.86653878 --> 00:14:46,372.86653878 Peptic ulcers form when there's an imbalance between mucosal defense mechanisms and aggressive factors like gastric acid and pepsin. 204 00:14:46,892.86553878 --> 00:14:48,692.86653878 The two main causes of PUD are H. 205 00:14:48,732.86653878 --> 00:14:50,642.86653878 pylori infection and NSAID use. 206 00:14:51,92.86653878 --> 00:14:57,272.86653878 In duodenal ulcers, excess acid secretion is usually the main problem, while in gastric ulcers, it's more about impaired mucosal defense. 207 00:14:58,122.86653878 --> 00:14:59,182.86653878 Aha, okay. 208 00:14:59,552.86653878 --> 00:15:01,972.86653878 So, again, we need to watch out for H. 209 00:15:02,2.86653878 --> 00:15:03,912.86653878 pylori and the NSAIDs. 210 00:15:03,922.86653878 --> 00:15:12,892.86553878 Yep, and remember that NSAIDs inhibit COX enzymes and prostaglandin synthesis, which impairs mucosal defenses by reducing mucus, bicarbonate secretion, and blood flow. 211 00:15:13,456.19987211 --> 00:15:23,976.19987211 Alright, but if someone shows up with these symptoms, how do you end up diagnosing PUD? Well, in order to tell if the problem is in the stomach or the duodenum, the key here is the timing of the pain. 212 00:15:24,331.19987211 --> 00:15:29,481.19987211 The pain in duodenal ulcers actually improves when you eat, and then gets worse again 2 3 hours later or at night. 213 00:15:29,941.19987211 --> 00:15:32,461.19987211 But the pain in gastric ulcers gets worse with eating. 214 00:15:33,111.19987211 --> 00:15:36,981.19987211 Then, if you go in with endoscopy, you would see an ulcer in the stomach or duodenum. 215 00:15:37,681.19987211 --> 00:15:41,91.19987211 For gastric ulcers specifically, you need to assess the risk of malignancy. 216 00:15:41,301.19987211 --> 00:15:48,491.19987211 Just by looking at it on endoscopy, a benign gastric ulcer will appear more clean and punched out, while a malignant one will have more heaped up margins. 217 00:15:48,841.19987211 --> 00:15:52,461.19987211 But to confirm or rule out malignancy in gastric ulcers, you will need a biopsy. 218 00:15:53,186.19987211 --> 00:15:58,826.19987211 Aha, so it is all about connecting the symptoms, timing, and what they see on the scope. 219 00:15:59,96.19987211 --> 00:15:59,826.19987211 Exactly. 220 00:16:00,346.19987211 --> 00:16:04,456.19987211 Plus, labs might show a positive urea breath test or stool antigen test for H. 221 00:16:04,486.19987211 --> 00:16:08,796.19987211 pylori and iron deficiency anemia if there's a chronic blood loss from the ulcer. 222 00:16:09,566.19987211 --> 00:16:17,236.19987211 Okay, and how do they fix it? Can they just cut back on the hot sauce or is there much more to it? There's definitely more involved. 223 00:16:17,346.19987211 --> 00:16:17,626.19987211 For H. 224 00:16:17,656.19987211 --> 00:16:22,736.19987211 pylori positive ulcers, it's the triple or quadruple therapy for 14 days like we mentioned earlier. 225 00:16:23,256.19987211 --> 00:16:28,516.19887211 For NSAID induced ulcers, stopping NSAIDs and starting a PPI for 8 weeks usually does the trick. 226 00:16:29,196.19987211 --> 00:16:35,226.19987211 In cases of complications like bleeding or perforation, endoscopic hemostasis or even surgery might be needed. 227 00:16:35,779.53220544 --> 00:16:38,429.53220544 Luckily though, prognosis is great if treated properly. 228 00:16:39,124.53320544 --> 00:16:41,474.5332054 Nice, sounds like a pretty straightforward plan. 229 00:16:41,824.5332054 --> 00:16:44,74.5332054 Kick out the bacteria or cut out the meds. 230 00:16:44,294.5332054 --> 00:16:44,914.5332054 You got it. 231 00:16:45,4.5332054 --> 00:16:46,624.5332054 Catch it early and you're good to go. 232 00:16:47,197.8655388 --> 00:16:52,67.8665388 Alright Radha, do you really, really want to guess what time it is? Quiz time! You got it. 233 00:16:52,577.8655388 --> 00:17:09,952.8665388 Now, which of the following is the most common complication of peptic ulcer disease? A, gastric outlet obstruction, B, perforation, C, bleeding, or D, fistula formation? The answer is C, bleeding. 234 00:17:10,302.8665388 --> 00:17:13,962.8665388 It's the most common complication occurring in about 15 to 20

percent of cases. 235 00:17:14,432.8665388 --> 00:17:23,852.8665388 Now should we move on to the gastric tumors? Not yet! We discussed a lot of diseases, so let's quickly recap the important points we mentioned before moving on to the next segment. 236 00:17:24,307.8665388 --> 00:17:25,217.8665388 Okay, let's do it. 237 00:17:26,448.871277 --> 00:17:26,908.871277 Alright. 238 00:17:27,468.871277 --> 00:17:33,152.2046103 Starting off with acute gastritis, acute gastritis can be caused by alcohol, NSAIDs, or stress. 239 00:17:33,270.042191 --> 00:17:36,430.042191 Endoscopy reveals reddish mucosa with small erosions. 240 00:17:36,800.042191 --> 00:17:41,300.041191 And biopsy shows neutrophilic infiltrates seen above the basement membrane. 241 00:17:41,650.042191 --> 00:17:45,50.042191 It is treated by PPIs and the stopping of the offending agent. 242 00:17:45,710.042191 --> 00:17:47,180.042191 Next up is stress ulcers. 243 00:17:47,480.042191 --> 00:17:51,330.042191 Krilling's ulcers are caused by severe burns and are often found in the proximal duodenum. 244 00:17:51,750.042191 --> 00:17:57,720.042191 Cushing's ulcers are a result of increased intracranial pressure and are often found in the stomach, duodenum, or even the esophagus. 245 00:17:57,940.041191 --> 00:18:03,880.041191 Endoscopy of stress ulcers reveals multiple small ulcers less than 1 cm with sharply demarcated edges. 246 00:18:04,420.042191 --> 00:18:04,890.042191 Alright. 247 00:18:05,360.042191 --> 00:18:11,490.042191 Chronic autoimmune gastritis is characterized by autoantibodies targeting parietal cells and intrinsic factor. 248 00:18:11,850.042191 --> 00:18:18,100.042191 This leads to achlorhydria, B12 deficiency, megaloblastic anemia, and high gastrin levels. 249 00:18:18,510.042191 --> 00:18:20,880.042191 This increases the risk of carcinoid tumors. 250 00:18:21,200.042191 --> 00:18:23,130.042191 And our main character of today's episode. 251 00:18:23,490.042191 --> 00:18:23,710.042191 H. 252 00:18:23,740.042191 --> 00:18:28,40.042191 pylori is a gram negative bacteria that uses urease and causes chronic gastritis. 253 00:18:28,400.042191 --> 00:18:31,800.041191 It poses a long term risk for malt lymphoma and adenocarcinoma. 254 00:18:32,220.042191 --> 00:18:36,320.042191 Diagnosis can be achieved by a positive urea breath test or stool antigen test. 255 00:18:36,540.041191 --> 00:18:40,910.042191 Treatment involves triple therapy of PPIs with clarithromycin and amoxicillin. 256 00:18:42,261.2915869 --> 00:18:45,711.2915869 Now, last but not least, we have peptic ulcers disease. 257 00:18:46,111.2915869 --> 00:18:50,291.2915869 This can either present as gastric ulcers or, more commonly, duodenal ulcers. 258 00:18:50,701.2915869 --> 00:18:56,551.2915869 Duodenal ulcers are usually benign, while the gastric ulcers carry a higher risk of malignancy. 259 00:18:56,901.2915869 --> 00:18:58,991.2905869 They're mostly caused by NSAIDs or H. 260 00:18:59,11.2915869 --> 00:18:59,611.2915869 pylori. 261 00:19:00,86.2915869 --> 00:19:08,136.2915869 The classic symptom is a burning pain in the stomach which worsens with meals in gastric ulcers and improves with meals in duodenal ulcers. 262 00:19:08,546.2915869 --> 00:19:11,496.2915869 The most common complication in both types is bleeding. 263 00:19:11,786.2915869 --> 00:19:15,606.2915869 This carries a risk of perforation and gastric outlet obstruction. 264 00:19:15,826.2915869 --> 00:19:17,116.2915869 That was quite the recap. 265 00:19:17,216.2905869 --> 00:19:18,576.2915869 Let's jump into our next case. 266 00:19:19,733.5307916 --> 00:19:24,823.5307916 Here, we have a 70 year old man who presents for a routine endoscopy due to a history of chronic gastritis. 267 00:19:25,403.5307916 --> 00:19:27,913.5307916 Endoscopy reveals multiple small polyps in the antrum. 268 00:19:28,113.5307916 --> 00:19:31,273.5307916 Biopsies confirm they are hyperplastic polyps with no dysplasia. 269 00:19:31,733.5307916 --> 00:19:32,703.5307916 Ooh, polyps. 270 00:19:33,413.5307916 --> 00:19:35,113.5297916 Those always sound a bit ominous. 271 00:19:35,303.5307916 --> 00:19:38,533.5317916 How worried should this guy be? Not too much in this case. 272 00:19:38,723.5307916 --> 00:19:42,593.5307916 These hyperplastic polyps are usually benign unless they're larger than 1. 273 00:19:42,593.6307916 --> 00:19:43,133.5307916 5 centimeters. 274 00:19:43,493.5307916 --> 00:19:48,268.4307916 Gastric polyps are mucosal protrusions that develop due to epithelial or stromal hyperplasia. 275 00:19:48,848.5307916 --> 00:19:53,618.5307916 Okay, so more like harmless bumps on the road, unless they start getting too big. 276 00:19:54,98.5307916 --> 00:19:54,838.5307916 Exactly. 277 00:19:54,918.5307916 --> 00:19:58,898.5297916 But adenomatous polyps are the ones to worry about since they carry a higher malignant potential. 278 00:19:59,218.5307916 --> 00:20:07,988.5317916 Okay, and how do these polyps form? Just too much cell growth, or is there more to it? Yup, it's mostly too much cell growth due to chronic inflammation. 279 00:20:08,348.5307916 --> 00:20:18,188.5307916 Hyperplastic polyps arise from regenerative hyperplasia of the gastric epithelium, while fundic gland polyps, on the other hand, are linked to increased gastrin levels due to long term PPI use. 280 00:20:18,718.5307916 --> 00:20:22,788.5307916 Uh huh, okay, so it's like overgrowth, but without the usual checks and balances. 281 00:20:22,798.5307916 --> 00:20:23,78.5307916 Yep. 282 00:20:23,948.5307916 --> 00:20:30,158.5307916 Okay, so if you find these polyps, do you take them out, or do you just keep an eye on them? That's actually a great question. 283 00:20:30,508.5307916 --> 00:20:33,848.5297916 Small hyperplastic polyps usually just need endoscopic surveillance. 284 00:20:34,28.5297916 --> 00:20:37,558.5307916 However, adenomatous polyps should be removed due to their malignant

potential. 285 00:20:37,968.5307916 --> 00:20:41,898.5307916 For fundigland polyps, no treatment is needed unless they're large or dysplastic. 286 00:20:42,8.5307916 --> 00:20:46,128.5307916 Got it, so it is a case of watchful waiting unless they look sketchy. 287 00:20:46,338.5307916 --> 00:20:47,8.5307916 Exactly. 288 00:20:47,473.5307916 --> 00:20:48,493.5307916 Now let me guess. 289 00:20:48,863.5307916 --> 00:20:56,243.5307916 Quiz time! You got it! So, which type of gastric polyp has the highest risk of malignant transformation? A. 290 00:20:56,583.5307916 --> 00:20:58,53.4297916 Hyperoplastic polyp. 291 00:20:58,233.5297916 --> 00:20:58,773.5297916 B. 292 00:20:58,943.5297916 --> 00:21:00,183.5297916 Fundic gland polyp. 293 00:21:00,593.5307916 --> 00:21:01,103.5307916 C. 294 00:21:01,103.6307916 --> 00:21:02,383.5297916 Adenomatous polyp. 295 00:21:02,743.5307916 --> 00:21:03,293.5307916 D. 296 00:21:03,463.5307916 --> 00:21:04,413.5307916 Inflammatory polyp. 297 00:21:07,201.910327 --> 00:21:08,671.909327 The answer is C. 298 00:21:08,741.910327 --> 00:21:09,756.810327 Adenomatous polyp. 299 00:21:10,66.910327 --> 00:21:13,436.910327 They have a high malignant potential, especially if larger than 2 centimeters. 300 00:21:13,786.910327 --> 00:21:14,376.910327 Noted. 301 00:21:14,636.910327 --> 00:21:15,666.910327 Let's keep it moving. 302 00:21:16,813.4493321 --> 00:21:22,173.4493321 Now, our next case is a 65 year old man who presents with weight loss, early satiety, and epigastric pain. 303 00:21:22,433.4493321 --> 00:21:24,453.4493321 He also reports melanoma for a few weeks. 304 00:21:24,773.4493321 --> 00:21:29,573.4483321 Endoscopy shows a large ulcerated mass in the antrum, and biopsies confirm adenocarcinoma. 305 00:21:30,563.4493321 --> 00:21:31,323.4493321 Yikes. 306 00:21:31,463.4493321 --> 00:21:34,413.4493321 Weight loss and melanoma? That's definitely alarming. 307 00:21:34,873.4493321 --> 00:21:38,303.4493321 What's the story here? Yeah, those symptoms are definitely concerning. 308 00:21:38,553.4493321 --> 00:21:44,753.4493321 This is gastric adenocarcinoma, which is the most common gastric malignancy, accounting for over 90 percent of stomach cancers. 309 00:21:45,103.4493321 --> 00:21:46,273.4493321 There are two main types. 310 00:21:46,643.4493321 --> 00:21:49,733.4493321 The first one is the intestinal type, where you have gland like structures. 311 00:21:50,53.4493321 --> 00:21:50,743.4483321 It is linked to H. 312 00:21:50,773.4483321 --> 00:21:53,593.4493321 pylori infection, chronic gastritis, and nitrosamines. 313 00:21:53,998.4493321 --> 00:21:58,228.4493321 The second type is the diffuse type, which has signet ring cells and does not form glands. 314 00:21:58,588.4493321 --> 00:22:05,238.3483321 It's linked to E cadherin mutations and is characterized by a leather bottled stomach, also known as linitis plastica. 315 00:22:05,418.4483321 --> 00:22:05,828.4493321 Got it. 316 00:22:05,938.4493321 --> 00:22:16,258.4493321 And how do these types of gastric cancers actually form? Are they both related to inflammation? Now, for the intestinal type, it usually starts with chronic inflammation, often from H. 317 00:22:16,278.4493321 --> 00:22:17,128.4493321 pylori infection. 318 00:22:17,488.4493321 --> 00:22:24,568.4493321 That leads to intestinal metaplasia and dysplasia, whereas for the diffuse type, it's more about genetic mutations, particularly in E. 319 00:22:24,578.4493321 --> 00:22:30,148.4493321 cadherin, which messes up cell adhesion and leads to that thickened, stiff stomach wall we call linitis plastica. 320 00:22:30,828.4493321 --> 00:22:37,278.4493321 Okay, so one's more of a slow buildup from inflammation, and the other is a genetic sneak attack. 321 00:22:37,558.4493321 --> 00:22:38,258.4493321 Exactly. 322 00:22:38,358.4493321 --> 00:22:40,838.4493321 Two different paths, same dangerous destination. 323 00:22:41,263.4493321 --> 00:22:53,313.4483321 Alright, so what kind of clues might point the doctors towards this diagnosis? So symptoms like weight loss, early satiety, epigastric pain, and melanoma are big red flags for malignancy. 324 00:22:53,783.4493321 --> 00:22:59,943.4493321 When you go in with endoscopy, you might find an ulcerated mass, or in the case of the diffuse type, a thickened stomach wall. 325 00:23:00,703.4493321 --> 00:23:03,433.4493321 Then we can continue with biopsy to distinguish the types. 326 00:23:03,863.4493321 --> 00:23:08,163.4483321 The intestinal type would have gland formation, and the diffuse type would have signet ring cells. 327 00:23:08,593.4493321 --> 00:23:15,43.4493321 And finally, we do a CT scan for staging and spotting metastases, like Burkhaus node or Sister Mary Joseph nodule. 328 00:23:15,683.4493321 --> 00:23:24,203.4493321 Okay, so once we've made the diagnosis, what's the treatment plan? Are we talking surgery, chemo, or both? Usually it's both. 329 00:23:24,453.4493321 --> 00:23:31,843.4493321 Surgical resection or gastrectomy is the main treatment if it's localized, but for more advanced stages, we would go for chemotherapy and radiation. 330 00:23:32,568.4493321 --> 00:23:40,528.4493321 When it comes to prognosis, a localized mass has a 5 year survival of up to 90%, but unfortunately, an advanced disease has less than 20%. 331 00:23:40,848.4493321 --> 00:23:44,688.4493321 Wow, so catching it early really makes a huge difference. 332 00:23:44,748.4493321 --> 00:23:45,468.4493321 Absolutely. 333 00:23:45,598.4493321 --> 00:23:46,998.4493321 Early detection is everything. 334 00:23:47,648.4493321 --> 00:23:58,348.4493321 Alright, Rahda, do you want to tell me what time it is? Quiz time! You got it! Which of the following is a characteristic finding of diffuse type gastric adenocarcinoma? A. 335 00:23:58,448.4493321 --> 00:24:00,298.4483321 Gland formation, B. 336 00:24:00,338.4483321 --> 00:24:02,218.4493321 Cygnet ring cells, C. 337

00:24:02,278.4493321 --> 00:24:04,408.4493321 Lymphoid aggregates, or D. 338 00:24:04,588.4493321 --> 00:24:11,189.1838197 Intestinal metaplasia? The answer is B, signet ring cells. 339 00:24:11,389.1838197 --> 00:24:14,429.1838197 Those are the hallmark of the diffuse type of gastric adenocarcinoma. 340 00:24:15,219.1838197 --> 00:24:15,759.1838197 Got it. 341 00:24:15,859.1838197 --> 00:24:16,909.1838197 Let's keep on moving. 342 00:24:18,119.6901773 --> 00:24:23,189.6901773 Next up, we have a 58 year old woman who presents with weight loss, abdominal discomfort, and early satiety. 343 00:24:23,549.6901773 --> 00:24:27,999.6901773 Endoscopy reveals thickened gastric folds and multiple ulcers in the body of the stomach. 344 00:24:28,429.6891773 --> 00:24:33,259.6891773 Biopsies show lymphocytic infiltrates with evidence of monoclonal B cell proliferation. 345 00:24:33,599.6901773 --> 00:24:34,859.6901773 Lymphomas in the stomach. 346 00:24:35,579.6901773 --> 00:24:37,739.6901773 I thought those were more of a lymph node thing. 347 00:24:38,349.6901773 --> 00:24:44,649.6901773 You're right, lymphomas usually start in lymph nodes, but gastric lymphomas are actually the most common type of extra nodal lymphoma. 348 00:24:45,99.6901773 --> 00:24:52,239.6901773 Most are malt lymphomas linked to h pylori infection, or we even have diffuse large B-cell lymphomas, which are more aggressive. 349 00:24:53,39.6901773 --> 00:24:56,749.6901773 Uh huh, so the stomach's playing host to some unwelcome guests. 350 00:24:57,9.6901773 --> 00:24:57,529.6901773 Got it. 351 00:24:57,639.6901773 --> 00:24:58,339.6901773 Exactly. 352 00:24:58,429.6901773 --> 00:25:01,139.6901773 And it's all about that chronic inflammation inviting the men. 353 00:25:01,459.6901773 --> 00:25:02,159.6901773 So how does H. 354 00:25:02,189.6901773 --> 00:25:07,779.6901773 pylori manage to turn stomach tissue into a lymphoma breeding ground? Well, chronic H. 355 00:25:07,799.6901773 --> 00:25:12,409.6901773 pylori infection causes continuous inflammation, leading to lymphoid tissue proliferation. 356 00:25:12,959.6901773 --> 00:25:18,179.6901773 Over time, this inflammation can trigger genetic changes, like the T1118 translocation. 357 00:25:18,679.6901773 --> 00:25:24,639.6901773 These changes activate NF kappa B, promoting B cell survival and eventually leading to malt lymphoma. 358 00:25:25,49.6891773 --> 00:25:28,99.6901773 Okay, so lymphoid tissue proliferation from chronic H. 359 00:25:28,139.6891773 --> 00:25:34,179.6901773 pylori leading to the T1118 translocation leading to the B cell malt lymphoma. 360 00:25:34,539.6901773 --> 00:25:35,849.6901773 Exactly, you got it. 361 00:25:36,259.6901773 --> 00:25:39,29.6901773 Alright, and how do we treat this? Do you just treat the H. 362 00:25:39,59.6901773 --> 00:25:40,929.6901773 pylori? Great question. 363 00:25:41,39.6901773 --> 00:25:42,729.6901773 For malt lymphoma, getting rid of H. 364 00:25:42,759.6901773 --> 00:25:45,459.6901773 pylori with antibiotics can actually induce remission. 365 00:25:45,769.6901773 --> 00:25:55,129.5901773 But, for more aggressive lymphomas, like diffuse large B cell lymphoma, it's all about CHOP chemotherapy, or CHOP, which includes cyclophosphamide. 366 00:25:55,299.6901773 --> 00:25:59,369.6901773 Doxorubicin, vincristine, and prednisone, often with rituximab. 367 00:25:59,789.6901773 --> 00:26:01,759.6901773 Okay, so it depends on the severity. 368 00:26:02,39.6901773 --> 00:26:02,649.6901773 Exactly. 369 00:26:02,969.6901773 --> 00:26:05,499.6901773 Different levels of intervention based on the threat level. 370 00:26:05,929.6891773 --> 00:26:08,419.6891773 Okay, we have another practice question rolling in. 371 00:26:08,829.6901773 --> 00:26:16,829.6901773 Which of the following infections is most commonly associated with gastric malt lymphoma? A, Epstein Barr virus, B, H. 372 00:26:16,859.6901773 --> 00:26:18,414.6901773 pylori, C. 373 00:26:18,424.6901773 --> 00:26:20,151.3901773 Cytomegalovirus or D. 374 00:26:20,151.3901773 --> 00:26:27,24.6901773 Hepatitis C virus? The answer is, of course, B. 375 00:26:27,64.6901773 --> 00:26:27,324.6901773 H. 376 00:26:27,354.6901773 --> 00:26:27,894.6901773 pylori. 377 00:26:28,174.6901773 --> 00:26:31,84.6901773 Chronic infection is the key risk factor for malt lymphoma. 378 00:26:31,464.6891773 --> 00:26:33,754.6891773 Nice! On to the next case. 379 00:26:34,919.0752452 --> 00:26:39,959.0752452 A 62-year-old woman with a history of pernicious anemia presents with abdominal pain and flushing. 380 00:26:40,349.0752452 --> 00:26:44,399.0752452 Endoscopy reveals a submucosal yellow 10 nodule in the gastric body. 381 00:26:44,909.0752452 --> 00:26:48,299.0752452 Biopsy confirms a well differentiated neuroendocrine tumor. 382 00:26:48,504.5854493 --> 00:26:54,144.5854493 Ooh, a neuroendocrine tumor? That sounds a bit different from the other stuff we've talked about. 383 00:26:54,424.5854493 --> 00:26:57,854.5854493 What's going on here? Now this is a gastric carcinoid tumor. 384 00:26:58,164.5844493 --> 00:27:04,964.5844493 There are well differentiated neuroendocrine tumors that arise from enterochromaffin like cells or ECL cells in the gastric mucosa. 385 00:27:05,434.5854493 --> 00:27:07,84.5854493 They're characterized into three types. 386 00:27:07,394.5854493 --> 00:27:11,314.5854493 Type 1 is linked to chronic atrophic gastritis and hypergastronemia. 387 00:27:11,804.5854493 --> 00:27:14,164.5854493 This type is the most common and least aggressive. 388 00:27:14,717.9187826 --> 00:27:18,817.9187826 Type 2 is associated with Zollinger Ellison syndrome and MEN1 syndrome. 389 00:27:19,107.9187826 --> 00:27:21,327.9187826 This type usually involves multiple lesions. 390 00:27:21,947.9187826 --> 00:27:23,677.9187826 Type 3 is the most aggressive one. 391 00:27:23,987.9187826 --> 00:27:26,247.9187826 It's sporadic and not linked

to hypergastronemia. 392 00:27:26,847.9187826 --> 00:27:32,7.9187826 Okay, so type 1 is mild, type 2 is in the middle, and type 3 is the most severe. 393 00:27:32,97.9187826 --> 00:27:36,567.9187826 Exactly, and they're all neuroendocrine tumors arising from anterior chromaffin like cells. 394 00:27:37,497.9187826 --> 00:27:41,167.9187826 So how do these carcinoid tumors form? Well, it depends on the type. 395 00:27:41,397.9187826 --> 00:27:43,717.9187826 Type 1 starts with chronic atrophic gastritis. 396 00:27:43,947.9187826 --> 00:27:47,237.9187826 If you remember, we said this has low stomach acid and high gastrin levels. 397 00:27:47,587.9187826 --> 00:27:52,187.9187826 All of this basically causes ECL cell hyperplasia and eventually carcinoid tumors. 398 00:27:52,657.9177826 --> 00:28:00,657.9187826 Whereas type 2 is driven by a gastrin secreting tumor called a gastrinoma that also elevates gastrin, leading to ECL cell hyperplasia. 399 00:28:01,77.9187826 --> 00:28:06,657.9177826 And finally, type 3 arises spontaneously with no connection to gastrin levels and tends to be more aggressive. 400 00:28:07,12.9187826 --> 00:28:13,542.9187826 Okay, so it's either too much gastrin causing cell overgrowth, or just bad luck with type 3. 401 00:28:14,42.9187826 --> 00:28:14,692.9187826 Exactly. 402 00:28:14,802.9187826 --> 00:28:16,602.9187826 Different pathways to the same problem. 403 00:28:16,892.9187826 --> 00:28:29,529.5854493 Alright, so if a doctor is trying to figure out if someone has a carcinoid tumor, what should they look for? Carcinoid tumors usually present with abdominal pain, flushing, and sometimes diarrhea if serotonin is secreted. 404 00:28:30,19.5854493 --> 00:28:35,129.5854493 Endoscopy would show submucosal yellow tan nodules, usually in the body and fundus of the stomach. 405 00:28:35,749.5854493 --> 00:28:42,889.5854493 If you perform biopsy, you would see uniform, round cells with salt and pepper chromatin positive for chromogranin A and synaptophysin. 406 00:28:43,209.5854493 --> 00:28:50,999.5854493 And finally, lab results would show high serum gastrin for types 1 and 2, and urinary 5 HIAA if serotonin is being secreted. 407 00:28:51,429.5844493 --> 00:28:58,559.4854493 Okay, so the cells are positive for chromogranin A and synaptophysin, and there is urinary 5 HIAA. 408 00:28:59,549.5854493 --> 00:29:04,459.5854493 Alright, so now what? Surgery, meds, or both? Both. 409 00:29:04,834.5854493 --> 00:29:05,994.5854493 Again, depending on the type. 410 00:29:06,454.5854493 --> 00:29:09,624.5854493 Type 1 and 2 can be resected endoscopically if the tumor is small. 411 00:29:10,4.5854493 --> 00:29:12,664.5854493 Then they can also be given octeotride for symptoms. 412 00:29:12,974.5854493 --> 00:29:18,357.9187826 These two types have a good prognosis, whereas type 3 has a poor prognosis due to its aggressive nature. 413 00:29:18,677.9187826 --> 00:29:21,517.9177826 This type needs surgical resection and often chemotherapy. 414 00:29:22,50.9620628 --> 00:29:22,770.9620628 Okay, got it. 415 00:29:22,820.9620628 --> 00:29:25,150.9630628 So, resection plus some sort of pharmacotherapy. 416 00:29:25,200.9630628 --> 00:29:25,820.9630628 Exactly. 417 00:29:26,715.9630628 --> 00:29:26,945.9630628 Hold on. 418 00:29:27,815.9630628 --> 00:29:38,185.9630628 You want to guess what time it is? Quiz time! You got it! Now, which type of gastric carcinoid tumor is associated with chronic atrophic gastritis and hypergastronemia? A. 419 00:29:38,245.9630628 --> 00:29:39,875.9630628 Type 1 B. 420 00:29:39,945.9630628 --> 00:29:41,265.9620628 Type 2 C. 421 00:29:41,265.9620628 --> 00:29:42,675.9620628 Type 3 or D. 422 00:29:42,725.9620628 --> 00:29:47,476.9541017 Type 4 The answer is A. 423 00:29:47,526.9551017 --> 00:30:03,824.7806591 Type 1 It's the one linked to chronic atrophic gastritis and high gastrin levels Nice! Let's move on to the last segment Okay, we're almost done A 55 year old man presents with abdominal pain and a palpable mass CT scan shows a well circumscribed submucosal mass in the stomach. 424 00:30:04,414.7806591 --> 00:30:09,349.6806591 Biopsy reveals spindle cells positive for a CD117 secant mutation. 425 00:30:10,189.7806591 --> 00:30:11,389.7806591 A genetic mutation. 426 00:30:11,449.7806591 --> 00:30:29,639.7806591 What's the story here? This is a gastrointestinal stromal tumor, or just for short, and is the most common mesenchymal tumor of the stomach just originates from the interstitial cells of Kal, which are the pacemakers of Paracelsus, and the tumor is driven by mutations in the CD one 17 C kit gene, or sometimes in P-D-G-F-R-A. 427 00:30:30,519.7806591 --> 00:30:30,929.7806591 Got it. 428 00:30:30,979.7806591 --> 00:30:33,89.7806591 So, GIST from CKIT mutation. 429 00:30:33,139.7806591 --> 00:30:38,519.7806591 But what's the deal with these CKIT mutations? Are they just random bad luck? Pretty much. 430 00:30:38,559.7806591 --> 00:30:44,939.7796591 Mutations in CKIT, or PDGFRA, lead to tyrosine kinase activation, causing uncontrolled cell proliferation. 431 00:30:45,409.7806591 --> 00:30:49,999.7806591 GISTs can range from benign to highly malignant based on their size and how fast they're dividing. 432 00:30:50,379.7806591 --> 00:30:50,979.7806591 I see. 433 00:30:51,29.7806591 --> 00:31:02,999.7806591 And how do doctors spot a GIST? The patient would present with abdominal pain, early satiety, and sometimes GI bleeding, prompting doctors to perform an endoscopy where they would see a submucosal mass that sometimes ulcerates. 434 00:31:03,399.7806591 --> 00:31:08,839.7806591 Then on biopsy, there are spindle cells positive for CD117 or CKIT and PDGFRA. 435 00:31:09,809.7796591 --> 00:31:10,179.7806591 Got it. 436 00:31:10,189.7806591 --> 00:31:15,669.7806591 So a submucosal mass with spindle cells that has a CKIT or PDGFRA mutation. 437 00:31:15,859.7806591 --> 00:31:16,689.7806591 Exactly. 438

00:31:16,839.7806591 --> 00:31:17,219.7806591 All right. 439 00:31:17,579.7806591 --> 00:31:28,134.7806591 And how do you get rid of these tumors? Surgery is the mainstay of treatment if it's resectable, but for unresectable or metastatic gists, you can use imatinib since it targets the CKIP pathway. 440 00:31:28,264.7806591 --> 00:31:30,464.7806591 Uh huh, so cut them out or use imatinib. 441 00:31:30,584.7796591 --> 00:31:31,204.7796591 Exactly. 442 00:31:31,294.7796591 --> 00:31:33,554.7806591 Different scenarios prompt different approaches. 443 00:31:33,814.7806591 --> 00:31:37,384.7796591 Alright, now we're approaching our last final question for today. 444 00:31:37,684.7796591 --> 00:31:49,924.7806591 Which marker is most commonly positive in a gastrointestinal stromal tumor? A CD 20 B, CD one 17 C, kit C, CD three, or D CD 30. 445 00:31:53,668.9274773 --> 00:31:59,358.9274773 The answer is B, CD one 17 or C kit, if you remember, it's the hallmark of gist. 446 00:31:59,448.9274773 --> 00:32:00,78.9274773 Nice. 447 00:32:00,348.9274773 --> 00:32:02,808.9274773 I feel like we've really covered the whole stomach today. 448 00:32:03,18.9274773 --> 00:32:05,748.9274773 Let's recap the gastric tumors to make sure we're good to go. 449 00:32:05,748.9274773 --> 00:32:06,588.9274773 All right, let's do it. 450 00:32:07,707.0595968 --> 00:32:12,87.0595968 Firstly, gastric polyps in the stomach are due to epithelial or stromal hyperplasia. 451 00:32:12,497.0595968 --> 00:32:15,587.0595968 They can either be hyperplastic polyps, which are the most common type. 452 00:32:15,917.0595968 --> 00:32:18,557.0595968 Or fund gland polyps or adenomatous polyps. 453 00:32:18,917.0595968 --> 00:32:28,957.0595968 Hyperplastic polyps are linked to chronic inflammation and are usually benign fund gland Polyps are often from PPI use, whereas adenomatous polyps carry a high risk of malignant transformation. 454 00:32:29,257.605883 --> 00:32:33,907.605883 Gastric polyps are usually asymptomatic unless they're really large, they might even cause bleeding. 455 00:32:34,512.9064075 --> 00:32:35,382.9064075 Alright, moving on. 456 00:32:35,382.9064075 --> 00:32:39,912.9064075 Gastric andino carcinomas includes the intestinal and diffuse types. 457 00:32:40,182.9064075 --> 00:32:42,342.9064075 The intestinal type is linked to h pylori. 458 00:32:42,772.9064075 --> 00:32:46,992.9064075 chronic gastritis and nitrosamines and forms gland like structures. 459 00:32:47,392.9064075 --> 00:32:56,222.9064075 The diffuse type involves signet ring cells and e cadherin mutations and may cause linidus plastica or a thick, stiff stomach. 460 00:32:56,282.9064075 --> 00:32:59,972.9074075 They usually spread to Virchow's nodes or sister Mary Joseph nodules. 461 00:33:00,468.8865061 --> 00:33:02,48.8875061 Now on to gastric lymphomas. 462 00:33:02,313.8875061 --> 00:33:05,503.8875061 These are classified into the more common Malt lymphoma linked to H. 463 00:33:05,523.8875061 --> 00:33:10,233.8875061 pylori infection and the less common, more aggressive, diffused large B cell lymphoma. 464 00:33:10,803.8875061 --> 00:33:12,853.8875061 Malt lymphoma is related to chronic H. 465 00:33:12,873.8875061 --> 00:33:19,183.8875061 pylori and a T1118 translocation, which activates NF kappa B and promotes B cell survival. 466 00:33:19,283.8875061 --> 00:33:21,333.8875061 Biopsy shows monoclonal B cells. 467 00:33:21,983.8875061 --> 00:33:29,93.8875061 Alright, now, gastric carcinoid tumors originate from ECL cells in the gastric mucosa and are of three types. 468 00:33:29,393.8875061 --> 00:33:33,623.8875061 Type one is linked to the chronic atrophic gastritis and is the least aggressive. 469 00:33:33,923.8875061 --> 00:33:41,393.8875061 Type two is linked to zore sison syndrome in MEN one syndrome, type three is sporadic and is the most aggressive type. 470 00:33:41,673.8875061 --> 00:33:48,33.8875061 Carcinoid tumors are submucosal tumors that stain positive for synaptophysin and chromogranin A and finally. 471 00:33:48,283.8875061 --> 00:33:53,93.8875061 GIST or gastrointestinal stromal tumors, which are the most common mesenchymal tumors in the stomach. 472 00:33:53,593.8875061 --> 00:34:03,891.0973904 These originate from the interstitial cells of KHAL and have spindle cells with either CKIT or CD117 or PDGFRA mutations causing excessive tyrosine kinase activity. 473 00:34:04,993.8865061 --> 00:34:13,153.8875061 Phew, we covered a lot today, from simple inflammation to polyps, cancers, lymphomas, and even some rare tumors. 474 00:34:13,333.8875061 --> 00:34:17,293.8875061 Yep, now our listeners know everything they need to know on gastric disorders. 475 00:34:17,788.8875061 --> 00:34:19,838.8875061 Thank you so much for the breakdown, Rada. 476 00:34:20,148.8875061 --> 00:34:23,818.8875061 And to all of our listeners, thank you for sticking with us and see you soon. 477 00:34:24,48.8875061 --> 00:34:24,548.8875061 Bye bye. 478 00:34:26,263.9671727 --> 00:34:27,283.9671727 Bloop, please. 479 00:34:28,368.9671727 --> 00:34:29,18.9671727 Quiz time. 480 00:34:29,263.9671727 --> 00:34:29,773.9671727 Quiz time. 481 00:34:30,523.9671727 --> 00:34:33,373.9671727 It's gonna get so annoying to whoever's listening to, I swear. 482 00:34:33,373.9671727 --> 00:34:38,863.9671727 Do you wanna get, do you wanna guess? Do, do you know what time, time, time.