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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.

Methotrexate, same as Azathioprine or Mercaptopurine, is NOT recommended for inducing remission , but to maintain remission. It can take up to 12 weeks to work However, these immunomodulators should be started earlier when patient is responding to first line treatment, in order to maintain remission and prevent flareups,  especially those with extensive disease or other poor prognostic features (early age at diagnosis, penetrating or stricturing disease, neeed for steroid, high CRP, smoker) should be considered for early introduction of biological therapy (dual biologic plus immunomodulator)

Active Crohn’s first line of treatment is an 8-week course of systemic corticosteroids to induce remission. Budesonide can be used  in mild-moderate case of ileal crohns, but should be escalated to systemic treatment if patient does not response.

Exclusive Enteral Nutrition (EEN) may be used to induce remission in mild to moderate Crohn’s disease patients where avoidance of corticosteroid is desired, and in those who are motivated to adhere strictly to EEN for up to 8 weeks. As this is a young male, this could be a possibility that may be worth exploring with paediatricians , dietitian and surgical team involvement. Howwever the fact that CRP is so high makes this case not  the ideal  candidate as he is already presenting systemic inflammation and there should be a good window of time needed  for this diet to work.

See BSG IBD guidelines 

 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. 

If patient had HGD / Adenoca on a Barrett´s oesophagus, then the lesion is removed or ablated and afterwards the Barretts is fully ablated, we should perform regular gastroscopies for surveillance after Barretts eradication- yearly for 5 years and then at year 7 and 10-  Check the guidelines

If the reason for the ablation was only low grade dysplasia, then the surveillance can be 1,3 and 5 years and than surveillance can be stopped.

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%)

Check the guidelines

The lower cutoff for FIB 4   >1.3.  Less than 1.3 rules out advanced fibrosis, and >1.3 needs further investigations.

In elderly patients (>65 yo) this threlsholds has low especificity (many false positive patients who do not really have advanced fibrosis) therefore the cutoff proposed in those is 2 (Fib 4 <2 rules out significant fibrosis)

>2.67 is the upper threshold for advanced fibrosis. Patients scoring this have high chance of advance fibrosis and should be referred to liver clinic

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

1. True.  Around 80%  of AIH will be either ANA or ASMA+, 8% AMA+, 2% LKM+. 30% SLA+
2.  True. Less than 50% in reduction of transaminases in 4 weeks after treatment is considered Non-response. (Occurs in 17% of treated patients and assoiciates a 7-fold risk of liver related death )
3.  False. Previous guidedlines suggested this parameter, but now we consider response when complete normalisation of transmanisases and IgG.   Liver biopsy is very useful to asses histological response if Modified Ishak hepatitis activity index (mHAI) <4 /18, however histology response lags behind biochemical response by several months: in one  RCT, only 28% and 50% of patients receiving prednisolone±azathioprine achieved histological remission after 6 and 12 months, respectively. Thus, repeat biopsy to confirm remission is not recommended over the first 2 years

4.  True. Since the response criteria are more strict, there will be 20-30% who wont achieve complete biochemical remission.  These scenarios are tricky, we need to compare the overall response, patient adeherence to treatment, considering Azathioprine adeherence and metabolism:  Measuring Thioguanin nucleotides- TGN-  to see that they are in therapeutic range(>220 pmol/8×10) and  Metilmercaptoruine ( MeMP) > 5700 can confirm that the patient is taking the right dose,  Also there are specific situations in which transaminases can remain slightly abnormal due to other causes like MASLD or drug related, and IgG is commonly raised in conditions like cirrhosis.

Check BSG guidelines AIH

Hb needs to be kept 7-8g/dl at least,  and a target of >9-10g/dl  if significant cardiovascular disease.  Andenaxet is recommended if life threatening or uncontrolled bleeding, like this case which is responding only partially to resucitation with fluids and continues to pass blood, so it could be prescribed.  If not available, 4-F PCC can be used instead.  Urgent sigmoidoscopy in general has no role and it would likely be useless without an adequate bowel preparation as we would expect to have very poor visibility due to stool and blood remains.

Unprepped colonoscopy or any form of sigmoidoscopy is NOT recommended in acute lower GI Bleeding unless very clear that the source is known to be anorectal or very distal colon (see American Guidelines) BSG guidelines also recommneds Colonoscopy as  inpatient with adequate bowel preparation, not urgently but  ideally after stabilising the patient.

If after resucitation and transfusion the patient remains unstable, then a joined plan with intensivist and surgical colleagues should be made (i.e, Interventional radiology, vs quick preparation with movicol, vs enema and salvage lower endoscopy, vs surgical approach)