GI Flashcards
What is necrotising enterocolitis?
Inflammation and necrosis of a portion of the GI tract.
What can increase the risk of necrotising enterocolitis?
IUGR.
What can decrease the risk of necrotising enterocolitis?
Breast feeding and probiotics.
Give 5 signs of necrotising enterocolitis.
- Feed intolerance.
- Bile-stained vomiting.
- Distended abdomen.
- Bloody stools.
- Shock.
How can you treat necrotising enterocolitis?
Broad spectrum antibiotics.
Give 4 causes of chronic constipation.
- Spurious/over-flow diarrhoea due to constipation.
- Chronic non-specific diarrhoea.
- Malabsorption.
- Enteric infection.
- IBD.
- Drug induced.
- Non-intestinal e.g. hypothyroidism
Give 2 non-intestinal causes of diarrhoea.
- Hyperthyroid.
2. Neuroblastoma.
Give 2 infective causes of diarrhoea.
- Adenovirus.
- Rotavirus.
- Protozoan: giardiasis.
What is the diagnostic criteria for giardiasis?
Cysts in stool and motile forms in small intestine.
How do you treat giardiasis?
3 days high dose metronidazole.
Briefly describe the pathophysiology behind lactose intolerance.
A deficiency of intestinal lactase prevents the hydrolysis of lactose. The osmotic load of the unabsorbed lactose causes secretion of fluid and electrolytes until osmotic equilibrium is reached -> diarrhoea.
What test can be done to check for lactose intolerance?
Hydrogen breath test.
With what immunoglobulins is cow’s milk allergy associated with?
IgG or IgE.
Give 3 symptoms of cow’s milk allergy.
- Vomiting.
- Abdominal pain.
- Diarrhoea.
- Malabsorption.
- Intestinal bleeding.
- Urticaria and lip swelling.
What is the treatment for cow’s milk allergy?
Specialised formula feeds.
A 6-month old breast fed infant developed widespread urticaria immediately after the first formula feed.
a) What investigation might you do?
b) What is the most likely diagnosis?
a) Skin-prick test for cow’s milk.
b) IgE mediated cow’s milk allergy.
A 4-month-old infant, formula fed since birth, has loose stools and faltering growth. Skin prick test to cow’s milk is negative but elimination of cow’s milk results in resolution of symptoms which return on trial re-introduction. What is the most likely diagnosis?
Non-IgE mediated cow’s milk allergy.
With which HLA molecules is Coeliac Disease often associated with?
DQ2 and DQ8.
Give 3 risk factors for developing Coeliac Disease.
- Family history.
- T1 Diabetes Mellitus.
- Down Syndrome.
- IgA deficiency.
- Often associated with other autoimmune disease.
Describe the diagnostic criteria for Coeliac Disease.
- Jejujunal biopsy showing characteristic histology e.g. villous atrophy, crypt hyperplasia, increased lymphocytes.
- endomysial and IgA TTG antibodies are useful screening tests
Describe Crohn’s disease.
A type of inflammatory bowel disease that affects anywhere from the mouth to the anus. It is characterised by patchy non-caseating granulomatous inflammation that can affect any layer of the bowel wall (transmural).
Give 9 features of Crohn’s Disease.
Classical presentation:
- abdominal pain
- diarrhoea
- weight loss
General ill health:
- fever
- lethargy
- weight loss
Extra-intestinal manifestations:
- Oral lesions
- Perianal skin tags
- Uveitis
- Arthralgia
- Erythema nodosum
Give 3 extra-intestinal signs of Crohn’s Disease.
- Oral ulcers.
- Uveitis.
- Arthralgia.
- Erythema nodosum.
Describe Ulcerative Colitis.
A type of inflammatory bowel disease that starts at the rectum and spreads proximally but only affects the colon. There is continuous inflammation that is confined to the mucosa.
Give 3 symptoms of Ulcerative Colitis.
- PR bleeding.
- Diarrhoea.
- Colicky pain.
- Weight loss.
- Growth failure.
Give 2 extra-intestinal signs of Ulcerative Colitis.
- Erythema nodosum.
- Arthritis.
- Iritis and episcleritis.
What investigations might you want to do on someone who you suspect has IBD?
- ESR and CRP.
- Measure Hb - will often have microcytic anaemia (IDA).
- Low serum albumin.
- Endoscopy and biopsy
What histological findings would you see on a biopsy taken from someone with IBD?
- Mucosal inflammation.
- Crypt damage.
- Ulceration.
Describe the treatment for Crohn’s.
Remission- steroids
Relapse:
- Immunosuppresants- azathioprine, mercaptopurine, methotrexate
- Anti-TNF agents- infliximab, adalimumab
Give 3 benefits of using immunosuppressants as opposed to steroids for the treatment of IBD.
- Safe.
- Effective.
- Steroid sparing.
- Prevent relapse.
Describe the mx of ulcerative colitis.
Mild:
- aminosalyclates- mesalazine
- topical steroids
Severe:
- Remission- azathioprine
- Corticosteroid