Inflammatory Bowel Disease Flashcards
What is the peak age of incidence for IBD?
20-30 years
What factors can cause IBD?
Environmental factors
Genetic predisposition
Host immune response
Gut microbiome
What are the differential diagnoses of IBD?
Infective colitis
Ischaemic colitis
What is the typical presentation fo infective colitis?
Short history of diarrhoea +/- vomiting Abrupt onset and resolution of sumptoms Systemic upset Predominant fever Often recent history of travel, unwell contacts or immunosuppressed
How is infective colitis investigated?
Stool culture
How is infective colitis treated?
Conservative management e.g. fluid replacement and analgesia
In what patients does ischaemic colitis usually occur?
Elderly
Cardiovascular diease
Heart failure
Ischaemic colitis is usually due to hypoperfusion rather than embolism. T/F?
True
What is the typical presentation of ishcaemic colitis?
Abrupt onset of pain and bloody diarrhoea
How is ischaemci colitis diagnosed?
CT showing segmental colitis especially in the watershed areas
How is ischaemic colitis treated?
Conservative management with IV fluids +/- antibiotics
How is toxic megacolon defined?
Megacolon seen on AXR (diameter >5.5cm or caecum >9cm) and signs of systemic toxicity
How is toxic megacolon treated?
Emergency colectomy
How should possible IBD be investigated?
Flexible sigmoidoscopy with biopsy
Describe the histological features of ulcerative colitis?
Crypt architectural changes which are generally very marked
Little or. no fibrosis
No granulomas
Inflammatory infiltrates in the whole. epithelium
Inflammation is mucosa-centric
Which part of the GI tract is typically affected by ulcerative colitis?
Extends from the rectum to involve the left side of the bowel
Terminal ileum only involved when whole of large colon including caecum is involved
How is ulcerative colitis treated?
5-ASA/mesalazine azathioprine/6MP IV corticosteroids Infliximab Surgery
Describe the dosing regimen for 5-ASA/mesesalazine in the treatment of ulcerative colitis?
4.8g initially and then 2.4g as daily maintenance
When should. azathioprine/6MP be prescribed for ulcerative colitis?
Severe. relpase
Frequently replacing disease
When >2 corticosteroid courses are required in a 12 month period
Disease replaces when steroid dose is reduced <15mg
Relapse within 6 weeks of stopping corticosteroids
Many ulcerative colitis patients are intolerant of azathiprine.6MP treatment. This also carries an increased risk of…?
Lymphoma
What drug is used to induce remission in midl to moderate ulcerative colitis?
5-ASA/mesesalazine
When should colectomy for ulcerative colitis patients be considered?
> 8 stools a day
>3 a day with CRP >45
What are the potential complications of ulcerative colitis?
Haemorrhage Toxic megacolon Erythema nodosum Pyoderma grangrenosum Sclerosing cholangitis Cholnagiocarcinoma Iritis Uveitis Episcleritis Ankylosing spondylitis Malignancy
What type of tumour accounts for the majority fo colorectal tumours?
Adenocarcinoma
Other than adenocarcinoma what other colorectal tumours can occur?
Neuroendocrine neoplasms Squamous cell caricnoma Metastatic carcinoma Adenosquamous carcinoma Gastrointestinal stromal tumours Melanoma Lymphoma
What gene mutations are often seen in colorectal cancer?
APC Beta catenin KRAS EGFR COX2 TP53 PIK3CA
What is a polyp?
An exophytic protuberant growth
Give examples of bowel polyps?
Hamartomous
Inflammatory
Hyperplastic
Adenomas
What factors of an adenoma influence its potential progression to carcinoma?
Size
Number
Villi
How often should low risk patients with IBD be screened for colorectal cancer?
Every 5 years
How often should medium risk patients with IBD be screened for colorectal cancer?
Every 3 years
How often should high risk patients with IBD be screened for colorectal cancer?
Every year
What is chron’s disease?
A chronic inflammatory condition which can affect any part of the GI tract from mouth to anus
Smoking increases the. risk of chron’s disease. T/F?
True - and stopping smoking reduces relapse rate and need for immunosuppression and surgery
What is the peak age of incidence of chron’s disease?
15-25 years
What are the signs and symptoms of chron’s disease?
Abdominal pain Diarrhoea (usually watery) Weight loss Fistulae Abscess Episcleritis Uveitis Sarcilitis Inflammatory arthropathy Erythema nodosum
How should potential chron’s disease be investigated?
Faecal calprotectin
MR/CT enterography
Ileocolonscopy and biopsy
Capsule endoscopy
What is faecal calprotectin?
A calcium binding protein which is predominantly derived from neutrophils
What is considered a normal faecal calprotectin level?
<50-200
Why is a faecal calprotectin test useful in the diagnosis of chron’s?
It differentiates IBD from IBS
What are the acute histological changes in chron’s disease?
Acute inflammation
Ulceration
Loss of goblet cells
crypt abscess formation
What are the chronic histological changes in chron’s disease?
Architectural changes Cell metaplasia Chronic inflammatory infiltrates in the lamina propria Neuronal hyperplasia Fibrosis Granulomas
How can UC and chron’s be differentiated pathologically?
Distribution of inflammation, type of inflammation and clinical context/scope findings
Azathioprine/6MP can be used to induce remission of chron’s disease. T/F?
False - it cannot be used to induce remission but can be used for maintenance of remission
Describe the dosing regimen for methotrexate in chron’s disease?
25mg/week IM for 16 weeks then 15mg a week
What biologics can be. used in the treatment of chron’s?
TNF-alpha antagonists e.g. infliximab, adalimumab
Anti-integrins e.g. vendolizumab
Anti-IL12/23 e.g. ustekinumab
