Digestive System
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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

For standard colonoscopies,  ASGE  and ESGE  agree that it should be an overall > 25% (for men ≥30%, for women ≥20%)

The  BSG minimum standard is slightly lower to > 15% (aspirational 20%)

Based on this metanalysis of real life Colonoscopy findings in >3.5 million patients, this percentage are pooled to real life colonoscopies

This rate is for standard colonoscopies, does not take into account FIT/FOBT  positive patients (Positive faecal blood patients in bowel screening) in which the aspirational should be at least 40-50% of adenoma or cancer detection. (See report from bowel screening in the UK)

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

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

According to the  2020 BSG  post-polypectomy surveillance guidelines   we recommend no surveillance if life expectancy is less than 10 y or patient older than 75 yo.  However this can be flexible depending on the patient situation. For example, if histology show incomplete resection margins or colonoscopy was suboptimally prepared then it could be reasonable to repeat the test in 1 year.

If this same case was in a fit and younger patient (e.g  65 yo patient ) then given that we removed 5  adenomas (premalignant) - this would be the cutoff to have another colonoscopy in 3 years

In fact, the majority of the guidelines suggest 3 year follow up if 5 or more small(<10mm)  adenomas are removed.  2020 AGA recommend 3 years followup if 5-10 adenomas, 5 years if 3-4 adenomas and up to 7-10 years if only 1-2 adenomas (or SSL).

For example, if a 65 yo patient had only 4 small adenomas with en bloc resection and good bowel cleaning,  no further surveillance and return to bowel screening according to the British guidelines but would need 5 year colonoscopy according to the AGA guidelines. 

According to the Haraldsson  classification, Type 2 and 3 are usually the most difficult- Type 3 is normally quite challenging as papilla is  protruding or bulging into the duodenal lumen or sometimes hanging down, pendulous , mobile and with the orifice oriented caudally. This papilla asociates a higher risk of failure OR 7.4 compared to type 1, followed closely by type 2 which is flat and small and associates also more risk of pancreatitis.
See image and data from retrospective database

This is a case of Clostridioides (Clostridium) difficile colitis with typical pseudomembranes on the colonic mucosa.  Elderly and nursing home patients are risk factors. We should take biopsies and ask for faecal sample (GDH and /or culture for toxigenic C.diff) because pseudomembrane rarely can have other causes (Staphylococcus aureus, CMV, radiation, ischemic, chemotherapy)

Patient does not meet the definition of Severe (>15000 leucocytes or deranged Creatinin) or fulminant (hypotension, septic shock, megacolon)

Most guidelines no longer recommend Metronidazole for C.diff as first line unless no other alternative available.  Despite ACG recommends either Vancomycin or Fidaxomicin as first line, (Fidaxomicin is more expensive) the European guidelines recommend Fidaxomicin over Vancomycin (Vancomycin is a perfect acceptable good choice , however despite both curing the infection in about the same rates (76.2% vs 70.5%),  lower recurrence rates with fidaxomicin are described (8.3% vs 32.6%) which could justify its higher cost.

Underwater EMR is a technique in which instead of gas, the colon is insuflated with liquid (usually water, less common saline). The water makes the mucosa 'float' by reducing the wall tension and this separates the layers of the mucosa-submucosa naturally without injecting lifting solution.  This makes flat polyps easy to get grasped. Scar appears small after resection, but when water is aspirated and air insuflatted, one can see the scars are usually much bigger than they appear with water.  See this image from Spadaccini et al 

Whenever an HCC (Hepatocelullar carcinoma) is resected in an early starge, 5-year recurrence occurs in up to 60-70% of the cases,  either as a result of intrahepatic metastases (true recurrent disease) or de novo cancer in the remaining cirrhotic liver .  However, similar rates of reccurence occurs if we use ablation instead of surgical resection (  between 60% and 85% recurrence with ablation) via the same mechanisms (either incomplete tumor erradication, or new tumor formation)

5-year recurrence after liver transplant is way lower (8-20%) and of course varies depending on the tumoral burden --> potential microvascular invasion at the time of the transplant.

See BSG guidelines

We need to differenciate between non dysplastic (the majority of Barrett's do not have any dysplasia, just metaplasia) versus dysplastic changes (proliferative changes that is characterized by a loss in the uniformity of individual cells in a tissue and loss in the architectural orientation )

The overall yearly incidence of  eosphageal adenocarcinoma in non dysplasitc  is 0.3% (. This is approximate and based on a metanalysis, although we know that factors such a age, smoking or obesity increase the overall risk of adenocarcinoma in Barrett's patients, and equally, the risk lowers when short segment (<3cm) - down to 0.19 % per year)

9.1% is the overall incidence of progression (to either HGD or adenoca) in those who already present low grade dysplasia, up to   9.1% per patient/year  with pooled annual incidence of adenocarcinoma of 0.54% per year