GI: IBS, IBD & Coeliac Disease Flashcards
What are the 2 main types of IBD?
1) Ulcerative colitis
2) Crohn’s disease
When does IBD typically present?
20s
General features of IBD?
Diarrhoea
Abdominal pain
Rectal bleeding
Fatigue
Weight loss
They are associated with periods of exacerbation and remission.
Differentiating features of Crohn’s can be remembered with the “crows” NESTS mnemonic:
N - No blood or mucus
E - Entire length of GI tract (i.e. mouth to anus)
S - Skip lesions
T - Transmural (full thicknes) inflammation/terminal ileum most affected
S - Smoking is a risk factor (don’t set the nest on fire)
Crohn’s is also associated with strictures and fistulas.
Differentiating features of ulcerative colitis can be remembered with the “you see (UC)” CLOSEUP mneumonic:
C - Continuous inflammation
L - Limited to colon and rectum
O - Only superficial mucosa affected
S - Smoking may be protective
E - Excrete blood and mucus
U - Use aminosalicylates
P - Primary sclerosing cholangitis
Would mouth ulcers indicate Crohn’s or UC?
Crohn’s
Give some other conditions that can occur in patients with IBD
1) Erythema nodosum
2) Pyoderma gangrenosum
3) Enteropathic arthritis
4) Primary sclerosing cholangitis (particularly UC)
5) Red eye conditions e.g., episcleritis, scleritis and anterior uveitis
What is erythema nodosum?
Tender, red nodules on the shins caused by inflammation of the subcutaneous fat
What is pyoderma gangrenosum?
rapidly enlarging, painful skin ulcers
What is enteropathic arthritis?
a type of inflammatory arthritis
Blood tests in IBD?
1) FBC (Hb low in anaemia), platelet count (raised in inflammation)
2) CRP
3) U&Es
4) LFTs (can show low albumin in severe disease –> protein is lost in the bowel)
5) TFTs for hyperthyroidism as a cause of diarrhoea
6) Anti-tissue transglutaminase antibodies (anti-TTG) for coeliac disease as a differential diagnosis
7) Vit D and B12 (often low)
What is anti-TTG a marker for?
Coeliac disease
Other investigations in IBD?
1) Stool microscopy and culture
2) Faecal calprotectin
3) Colonoscopy with multiple intestinal biopsies
4) Imaging investigations e.g. US, CT and MRI
Purpose of LFTs in IBD?
can show low albumin in severe disease (protein is lost in the bowel)
Purpose of TFTs in IBD?
hyperthyroidism as a cause of diarrhoea
Purpose of anti-TTG antibodies in IBD?
for coeliac disease as a differential diagnosis
Purpose of stool microscopy and culture in IBD?
to exclude infection as a differential diagnosis (e.g., Salmonella)
Purpose of faecal calprotectin in IBD?
Is around 90% sensitive and specific for inflammatory bowel disease in adults.
It is used as an initial test before moving on to endoscopy.
Investigation of choice in establishing diagnosis in IBD?
Coloscopy with multiple intestinal biopsies
Purpose of imaging investigations in IBD?
to look for complications such as fistulas, abscesses and strictures.
Management of mild to moderate acute UC?
1st line –> aminosalicylate (e.g., oral or rectal mesalazine)
2nd line –> corticosteroids e.g. oral or rectal prednisolone
Management of severe acute UC?
1st line –> IV steroids (e.g. IV hydrocortisone)
Other options:
1) Intravenous ciclosporin
2) Infliximab
3) Surgery
Curative treatment for UC?
Panproctocolectomy –> removing the entire large bowel and rectum
Following a panproctocolectomy, the patient has either a permanent ileostomy or an ileo-anal anastomosis (J-pouch).
What is an ileostomy?
An ileostomy is where the end portion of the small bowel (ileum) is brought onto the skin with a spout that drains stools directly into a tightly fitting stoma bag.
What is a J pouch?
A J-pouch is where the ileum (small bowel) is folded back on itself and fashioned into a larger pouch, which is attached to the anus and functions like a rectum, collecting stools before the person opens their bowels.
1st line management of an exacerbation of Crohn’s?
Steroids (e.g., oral prednisolone or IV hydrocortisone) first-line
What is an alternative to steroids in Crohn’s, particularly where there are concerns about steroids affecting growth?
Enteral nutrition –> a specially formulated liquid diet given orally or by NG feed that replaces the patient’s diet.
How can enteral nutrition induce Crohn’s remission?
1) Treating nutritional deficiencies
2) Improving the gut microbiome
3) Removing inflammatory foods
When steroids alone are inadequate in Crohn’s, what can be added?
Azathioprine
Mercaptopurine
Methotrexate
Infliximab
Adalimumab
1st line for maintaining remission in Crohn’s?
1) Azathioprine
2) Mercaptopurine
Maintaining remission in Crohn’s disease is tailored to the individual, based on risks, side effects, nature of the disease and patient wishes. This might also involve no medications.
What is an alternative for maintaining remission in Crohn’s where 1st line options are not suitable?
Methotrexate
Surgical options for Crohn’s?
1) Resecting the distal ileum when the disease is isolated to this area
2) Treating strictures
3) Treating fistulas
Where does Crohn’s disease most commonly affect?
Terminal ileum (but may be seen anywhere from the mouth to anus)
Features of Crohn’s disease
- non-specific symptoms such as weight loss and lethargy
- diarrhoea: most prominent symptom in adults, may be bloody diarrhoea
- abdo pain
- perianal disease e.g. skin tags or ulcers
- extra-intestinal features
Is primary sclerosing cholangitis more common in Crohn’s or UC?
UC
What is the most common extra-intestinal feature in both CD and UC?
Arthritis
Is episcleritis more common in Crohn’s or UC?
Crohn’s
Is uveitis more common in Crohn’s or UC?
UC
Complications of Crohn’s?
small bowel cancer (standard incidence ratio = 40)
colorectal cancer (standard incidence ratio = 2, i.e. less than the risk associated with ulcerative colitis)
osteoporosis
Features of UC?
- bloody diarrhoea
- urgency
- tenesmus
- abdominal pain, particularly in the left lower quadrant
- extra-intestinal features
Typical findings on coloscopy and biopsy in UC?
red, raw mucosa, bleeds easily
no inflammation beyond submucosa (unless fulminant disease)
widespread ulceration with preservation of adjacent mucosa which has the appearance of polyps (‘pseudopolyps’)
inflammatory cell infiltrate in lamina propria
neutrophils migrate through the walls of glands to form crypt abscesses
depletion of goblet cells and mucin from gland epithelium
granulomas are infrequent
What may be linked to an UC flare?
1) stress
2) medications e.g. NSAIDs, antibiotics
3) cessation of smoking
When can a diagnosis of IBS be considered?
If the patient has had the following for at least 6 months:
1) Abdominal pain, and/or
2) Bloating, and/or
3) Change in bowel habit e.g. watery, loose, hard
When can positive diagnosis of IBS be MADE?
If the patient has abdominal pain relieved by defecation or associated with altered bowel frequency stool form, in addition to 2 of the following 4 symptoms:
1) altered stool passage (straining, urgency, incomplete evacuation)
2) abdominal bloating (more common in women than men), distension, tension or hardness
3) symptoms made worse by eating
4) passage of mucus