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 Low amplitude propagated contractions (LAPC) Haustral contractions, triggered by chyme, facilitate the slow movement and mixing of food to enhance water absorption. Those are slow, segmenting movements that further mix chyme, most comoon in proximal colon.  (5 to 40 mm Hg) and last about 3  seconds.They happen  about every 30 minutes. 

It is not 2 times higher, it is actually > 10 times higher!!

This is the reason ADR is probably  the most important surrogate marker of a good  quality colonoscopy, (others are bowel preparation, caecal intubation and withdrawal time) and we need to maintain ADR  at least >20%

Misty mesentery refers to a non-specific radiological finding characterized by increased attenuation within the mesenteric fat on computed tomography  imaging.  It mimics mistiness as localised fat stranding in the mesentery.  Many processes can lead to the appearance including infiltration by inflammatory cells, oedema, lymphatic accumulation, haemorrhage, tumour infiltration, and fibrosis.  Tipically reflects mesentery panniculitis  ( rare  benign condition characterized by chronic inflammation  of adipose tissue mainly of the small bowel mesentery) But can be the results of any inflammatory or neoplasic process. That is why it is needed to consider also vasculitis, lymphomas, inflammatory process or GI neoplasia.

Difficult case with patient older than 65 and comorbidities with moderately to severely active ulcerative colitis.

Vedolizumab should be indicated in his case as it performs better than anti TNFs in ulcerative colitis, confirming the results of the Varsity study.   ( Over a 5 year period, drug persistence is higher in patients treated with vedolizumab as compared to anti-TNF therapies and loss of response is less frequent again in the vedolizumab group). Age or previous TIA /AV block are not contraindications for anti-TNF (only Moderate-severe heart failure, which is not the case) So even though Adalimumab would be a valid option, it should be ideally used if Vedolizumab fails.

JAK inhibitor (Tofacitinib) should not be prescribed in people with a history of cardiovascular disease (eg. heart attack or stroke) at increased risk of cardiovascular problems (eg. current or past long-time smokers) at increased risk of cancer or aged 65 years and over unless no suitable alternative

Ozanibod could be an oral alternative , however second-degree Mobitz type II atrioventricular (AV) bloc and TIA within the previous 6 months contraindicates its use.

Off the quizz options, another good one would be Ustekinumab (interleukin 12&23 antagonist drug ) as not contraindicated here and equally valid to Vedolizumab.

Based on this study by O Sullivan et al where 2451 LNPCPs (Large non pedunculated colonic polyps)  were analyzed after resection and found and average of 10% had submucosal invasive cancer (SMIC).  Previously, overall described SMIC had been reported around 7.6%–8.5% of endoscopically resected LNPCPs.   The higher risk were the depressed polyps ( 60%) followed by non granular (20%) or granular in rectosigmoid (20%)

Mucosal xantoma - benign lesion composed of foamy macrophages within the lamina propria. fibrovascular. They presents as discrete single to multiple yellowish-white patches, most commonly in the antrum or pyloric region of the stomach . Endoscopically it sometimes can resemble candidiasis, polyp, lymphangiectasia, Russell body gastritis, and Pseudoxanthoma elastic or gastric malignancy.

Lymphangiectasia would have showed prominent dilated lymphatics in the lamina propria region of the villous structure, often with extension into submucosa . These are more commonly seen in duodenum or terminal ileum

Underwater EMR offers the advantage of keeping the polyp surface small in flat polyps (opposite to when we inject lifting solution where the polyp keeps spreading and this makes grabbing the polyp en bloc more difficult) this explains why is a good method to remove en bloc lesions bigger than 10mm (Ideally even bigger than 20mm, although even with U-EMR the bigger the polyp, the more difficult to obtain full resected piece en bloc. This results are published in endoscopy in this meta analysis

Despite they all are good options that could be considered. We need to see:

• Size (abut 12-13mm in size)
• Mucosal pattern (looks like sessile serrated lession or SSP-  with clouded surface and indistictive borders - see  WASP classification - : The lesion has NO suspicious areas of submucosal invasion
• Shape- 0-IIa of Paris classification (despite the name sessile serrated lesion, this is the nomenclature for that type of serrated lesions, although the majority of them are in fact flat, not sessile)
• Position- Right vs left colon (risk of perforation,  lesion is easy accesible or not in case of delayed bleed)

With all in mind, the most difficult option would be cold snare as >10mm and having broad base, it would be difficult to fully grasp the tissue, close and cut through with cold snare. ESGE guidelines recommend cold snare in small (<10mm ) and in >10mm they suggest hot polypectomy or piecemeal cold snare resection.

So the options would be 1) Lifting and use the cold snare to resect either en bloc if feasible, or most likely piecemeal 2) Do the same but using diathermy with a hot snare or 3) do not lift and use underwater EMR, which probably would allow to grab the lesion en bloc, completely in one go with a 15mm snare. Despite ESGE recommends underwater EMR in selected cases >20mm, realistically if we want en bloc resection, it is either hot snare or underwater EMR.

Note that cold EMR is also a good option for SSL, has an excellent safety profile with less adverse events compared to hot EMR, and less residual rate (1% in cold vs 4.2% in hot) in serrated lesions, however requires some level of practice and getting used to a slighly more bleeding field.

According to the US Hpylori Guidelines, BQT  is the first option for both standard and penicillin allergic patients.  This is a PPI (standard dose)  b.i.d.   Bismuth subcitrate (120–300 mg) or subsalicylate (300 mg) q.i.d. Tetracycline (500 mg)e q.i.d. and Metronidazole (500 mg) t.i.d. or q.i.d

In treatment-experienced patients with persistent H. pylori infection  , they recommend O+L+  either Amoxicillin or Metronidazole

Even though only 10% of hep B infections will become chronic and we have an effective vaccination that can virtually prevent infection, the reality is that hepatitis B incidence and prevalence is very high.  WHO estimates that 254 million people were living with chronic hepatitis B infection in 2022, with 1.2 million new infections each year. Maternal-to-newborn perinatal transmission of the virus can be high (70 to 90% in HBeAg-positive-indicating high viral replication-, or 10% to 30% if the mother is HBeAg-negative )

Hepatitis C , despite easy to become chronic (80% of infections) and no effective vaccine, is less common, (Estimated 50 million worldwide) partly because the vertical transmission is low and also because the new  direct-acting antiviral (DAA) tablets are highly effective at clearing the infection in more than 90% , reducing transmission.