12- Paediatric Gastroenterology (2/2) Flashcards
Inflamamtory bowel disease background
Inflammatory bowel disease is the umbrella term for the two main diseases that cause inflammation of the GI tract:
- Ulcerative colitis
- Crohn’s disease.
UC vs Crohns
pathophysiology of IBD
They both involve inflammation of the walls of the GI tract due to autoimmune activity and are associated with periods of remission and exacerbation.
RF for IBD
- Age <30
- Whites highest risk
- Family history
- Cig smoking
-> Crohns
->UC- Non smoker - NSAIDs medication
general presentation of IBD
Suspect inflammatory bowel disease in children and teenagers presenting with perfuse diarrhoea, abdominal pain, bleeding, weight loss or anaemia. They may be systemically unwell during flares, with fevers, malaise and dehydration.
Extraintestinal manifestations of IBD
o Finger clubbing
o Erythema nodosum
o Pyoderma gangrenosum
o Inflammatory arthritis
o Primary sclerosing cholangitis (UC)
investigations for IBD
- blood tests
- stool tests
- simple imaging
- endoscopy
- detailed imaging
blood tests for IBD
- FBC- anaemia
- U and E- deranged electrolytes due to AKI due to GI losses
- CRP – active inflammation
stool tests for IBD
- Stool cultures- exclude infective colitis
- Faecal calprotectin- raised in active disease and negative in irritable bowel or IBD in remission, but not specific to IBD and shouldn’t be used if blood is present as the presence of blood requires further investigation
simple imaging for IBD
AXR
- Used less commonly but used if suspicion of toxic megacolon and can be useful to assess for proximal constipation
- Strings of kantour- Crohns
- Lead pipe colon- UC
endoscopy for IBD
OGD and colonoscopy- gold standard
- Flexible sigmoidoscopy- safest test in bloody diarrhoea
- Colonoscopy- needed to look for more proximal disease
- Capsule endoscopy- useful to view small bowel mucosa
detailed imaging for IBD
- Acute complications
- CT/ MRI enterography when looking for small bowel crohns, fistulas or to map the extent of small bowel crohns
- MRI rectum is image perianal crohns
general managements for IBD
- MDT
- Monitor growth and pubertal development
-> Dietician
-> Careful steroid use - Management involves inducing remission during flares and maintaining remission when well
features of UC
Ulcerative colitis
Inflammatory bowel disease characterised by diffuse inflammation of the colonic mucosa
It affects the rectum and extends proximally : distal (proctitis), left sided (splenic flexure) and extensive (beyond splenic flexure)
- Can be up to 40 bloody stools a day
- Blood and mucous= affecting mucosa
- Weight loss -> inflammation uses a lot of calories and diarrhoea can make you lose appetite
- Mild lower abdominal pain
- Normal temp
- Painful red eye-? extraintestinal problem
- Nocturnal symptoms
- Urgency
- Tenesmus
- X-ray- lead pipe colon
pathophysiology of UC
- Chronic inflammatory infiltrate of lamina propria
- Crypt abscesses (Neutrophilic exudate in crypts)
- Crypt distortion (bottom image)
o Irregular shaped gland with dysplasia
o Darker crowded nuclei - Reduced numbers of goblet cells
- Pseudo polyps can develop after repeated episodes
o Inflammation then healing
o Nonneoplastic
o More common in UC ( vs Crohns) - Loss of haustra
o Inflammation reduces the appeared of haustra on imaging
loss of haustra in UC
features of crohns
- Diarrheal – non bloody
- Mildly anaemic
- Low grade fever
- Weight loss
o Any inflammations stops us absorbing things-> diarrhoea -> weight loss
o Osmotic pressure drawing water out into the lumen - Unlikely to have bleeding
o Deeper but less widespread - Tender mass RLQ
o Terminal ileum common site - Mild perianal inflammation -> fistulas and strictures
pathophysiology of Crohns
- Skip lesions
- Hyperaemia- red and inflamed
- Mucosal oedema cobblestones are oedematous
- Transmural inflammation
o Thickening of bowel wall
o Narrowing of lumen - Granuloma formation -> pathognomonic for crohns
management of UC: inducing remission
Mild to moderate disease
- First line: amino salicylate (e.g. mesalazine oral or rectal)
- Second line: corticosteroids (e.g. prednisolone)
Severe disease
- First line: IV corticosteroids (e.g. hydrocortisone)
- Second line: IV ciclosporin
maintaing remission of UC
- Aminosalicylate (e.g. mesalazine oral or rectal)
- Azathioprine
- Mercaptopurine
surgery for UC
- Only affects colon and rectum therefore pan proctocolectomy will remove all disease
o Permanent ileostomy or something called a J-pouch
Crohns inducing remission
- First line: steroids e.g. oral prednisolone or IV hydrocortisone
- Second line: immunosuppressant medication
o Azathioprine
o Mercaptopurine
o Methotrexate
Crohns maintaining remission
First line:
* Azathioprine
* Mercaptopurine
Alternatives:
* Methotrexate
* Infliximab
* Adalimumab
surgery for Crohns
- Resection not as useful as in UC due to Crohn’s being able to spread everywhere
- When the disease only affects the distal ileum it is possible to surgically resect to prevent further flares
- For strictures and fistulas
jaundice
clinical manifestation of increased bilirubin the blood
- Yellow discolouration of sclera and the skin
bilirubin metabolism
When Hb goes to the Spleen it is broken down into haem and globin
1) Globin
2) Haem
- Converted to biliverdin (unconjugated)
- Transported via albumin to the liver
- Liver conjugates bilirubin to make it water soluble
- Can enter entero- hepatic circulation
- Can travel down to duodenum and stay in the gut
- Oxidised to stercobilin – makes faecal matter brown
- Can go to the kidney and be excreted as urobilinogen
causes of jaundice
Pre-hepatic
Hepatic
Post-hepatic
pre-hepatic jaundice
1) Too much break down of HB –>haem
- Haemaglobinopathies
* Sickle cell
* Thalamasemia
* Spherocytosis
2) Haemolysis
3) Too much demand for liver e.g. newborn
4) Liver cant conjugate it all
5) Therefore some bilirubin is unconjugated
hepatic causes of jaundice
- Liver function down (reduced hepatocyte function)
- Reduced conjugating ability of the liver
- Causes
1) Chronic liver disease
2) Acute liver damage
post-hepatic causes of jaundice
- Any obstructive condition to the bile duct -> if any part of excretion pathway is obstructed e.g. gall stones
- Most common jaundice - Type of bilirubin likely to be raised is conjugated -> water soluble -> goes through blood stream to the kidney
- More bilirubin excreted by the kidney
- Therefore discolouration of the urine
- Dark urine, pale stools
causes of post-hepatic jaundice
- Gall stones**
- Inflammation which causes scarring or narrowing of the biliary tree
- Enlargement of the head of the pancreas** (pancreatic carcinoma) ->painless jaundice (red flag)
- Intrahepatic obstruction within the liver**
- Inflammation/ oedema
- Tumour e.g. hepatocellular carcinoma (compression locally)
- Cirrhosis- no expansile - Compresses veins – portal hypertension
- Also compresses bile ducts in liver
jaundice blood levels
> 25-30 mmol/L
jaundice in children
- Rare outside neonatal period