Gastroenterology Flashcards
What is GOR?
the passage of gastric contents into the oesophagus and is normal in infants if it is asymptomatic.
What is GORD?
the passage of gastric contents into the oesophagus, it is the term used to describe this process in the presence of symptoms or complications from the reflux
What is coeliac disease?
A life long gluten-sensitive autoimmune disease of the small intestine.
What genetic components are linked to coeliac disease?
HLA-DQ2/DQ8
What signs on microscopic investigation can be seen in coeliac disease?
epithelial cell destruction and villous atrophy
Gluten protein is found in which types of cereal?
Wheat
Barley
Rye
Name some conditions related with coeliac disease.
Type 1 diabetes
Down syndrome
Turner syndrome
Other autoimmune diseases, such as thyroid disease, rheumatoid arthritis & Addison’s disease
Describe how a child with coeliac disease might present.
Most common presentation at 9-24 months of age with features of malabsorption, such as failure to thrive/ weight loss, loose stool, steatorrhea, anorexia, abdominal pain, abdominal distention, muscle waste. Child is often miserable with behavioral changes. Histology reveals crypt hyperplasia and villous atrophy.
Name some extra-intestinal symptoms in patients with coeliac disease.
Dermatitis herpetiformis Dental enamel hypoplasia Osteoporosis Delayed puberty Short stature Iron- deficient anaemia- resistant to oral Fe Liver and biliary tract disease Arthritis Peripheral neuropathy, epilepsy, ataxia
What is tested for in the serology of suspected coeliac disease?
Test for total immunoglobulin A (IgA) and IgA tissue transglutaminase (tTG) as the first choice
If serology is positive for coeliac disease, what diagnostic test should be performed?
Endoscopic intestinal biopsy is necessary when the serology is positive
What is the gold standard test to diagnose a child with coeliac disease?
Duodenal biopsy
What cell mediated autoimmune response occurs in coeliac disease?
T cell mediated
Investigations for Coeliac disease will only be correct if the patient has been on a diet containing gluten for at least how long?
6 weeks
In cows milk protein allergy, what proteins produce an immune-mediated allergic response?
Casein and whey
How is CMPA classified?
IgE-mediated, non-IgE-mediated, and mixed.
Describe the pathophysiology of IgE mediated CMPA.
CD4+ TH2 cells stimulate B cells to produce IgE antibodies against cow’s milk protein which trigger the release of histamine and other cytokines from mast cells and basophils.
Describe the pathophysiology of Non IgE mediated CMPA.
T cell activation against CMP
How is CMPA managed?
An elimination diet is required for a least 6 months or until infant is 9-12 months old, with re-evaluation of the infant every 6 to 12 months to assess for tolerance to cow’s milk protein.
What formula can be used n infants with CMPA?
Extensively hydrolysed formula: cheaper, first-line formula made from cow’s milk but the casein and whey are broken down into smaller peptides which are less immunogenic. 90% of children with CMPA will respond to this.
Amino acid formula: more expensive, second-line formula for the 10% children who continue to have symptoms despite using hydrolysed formula or who have very severe symptoms.
How does gastroenteritis present?
Sudden onset diarrhoea with or without vomiting.
What are the most common isolates of gastroenteritis?
Rotavirus
Campylobacter
Which of the common isolates of gastroenteritis are vaccinated against in the National Vaccination Programme in the UK?
Rotavirus
What should be discouraged in a child that is at risk of dehydration?
fruit juices and carbonated drinks
What are he maintenance fluids required for a child that is 0-10kg?
100ml/kg/day
What are he maintenance fluids required for a child that is 10-20kg?
1000ml+ 50ml/kg/day
What are he maintenance fluids required for a child that is >20kg?
1500ml+ 20ml/kg/day
What advise should a child be given following rehydration after an episode of gastroenteritis?
- Avoid sharing towels
- Do not return to school before 48hr
- Do not swim for 2 weeks
Name some complications of gastroenteritis.
- Haemolytic uraemia sundrome
- Reactive complications i.e. Reiter’s syndrome (urethritis, arthritis, uveitis)
- Toxic megacolon
- Secondary lactose intolernce
Describe the bimodal peak age presentation of Crohn’s disease.
Between 15-30 and 60-80
Where does Crohn’s disease commonly affect?
Distal ileum or proximal colon
How is Crohn’s disease clinically characterised?
Transmural inflammation, deep ulcers and fissures (cobblestone appearance), skip lesions.
Describe the microscopic appearance of Crohn’s disease.
Non-caseating granulomatous inflammation
Describe the difference between Crohn’s and UC in relation to the site involvement.
Crohn’s: Entire GI tract
UC: Large bowel
Describe the difference between Crohn’s and UC in relation to the inflammation.
Crohn’s: transmural
UC: mucosa only
Describe the difference between Crohn’s and UC in relation to the microscopic changes.
Crohn’s: granulomatous (non-caseating)
UC: Crypt abscess formation, reduced goblet cells, non-granulomatous
Describe the difference between Crohn’s and UC in relation to the macroscopic changes.
Crohn’s: Skip lesions, cobblestone appearance, fistula formation
UC: continuous inflammation (proximal from rectum), pseudopolyps, ulcers
Name some risk factors of developing Crohn’s disease.
- 20% family history
- Smoking
- White European descent
- Appendectomy
Describe how Crohn’s disease would present.
Episodic abdo pain, diarrhoea perhaps containing blood or mucus.
Systemic symptoms include malaise, anorexia, low-grade fever.
Name the 3 types of imaging that can be utilised in the diagnosis of Crohn’s disease.
- Colonoscopy with biopsy
- CT - abdo/pelvis
- MRI
Describe the medical management of remission of Crohn’s disease.
- Fluid resuscitation
- Nutritional support
- Prophylactic heparin
- Corticosteriod therapy
- Immunosuppresent agents i.e. Azathioprine
Describe the medical management of maintaining remission of Crohn’s disease.
Monotherapy i.e. Azathioprine
Biological agents i.e. infliximab
Smoking cessation
Which investigation should be avoided during an acute flare of Crohn’s disease and why?
Colonoscopy - increased risk of perforation
Describe the bimodal peak age presentation of UC.
15-25 years and 55-65 years
Describe the prevention of UC.
Insidious onset with bloody stools (90% of cases). Often PR bleeding with mucus discharge
What criteria can be used to grade UC?
Truelove and Witt
What is the definitive diagnosis for uC?
Colonoscopy with biopsy
Describe the AXR findings during UC.
- Toxic megacolon
- Mural thickening
- Thumbprinting
- Lead pipe colon
Describe the medical management of remission of UC.
- Fluid resuscitation
- Nutritional support
- Prophylactic heparin
- Corticosteriod therapy
- Immunosuppresent agents i.e. Azathioprine
Describe the medical management of maintaining remission of UC.
Immunomodulators i.e. Mesalazine
What is the cure for UC?
Total proctocolectomy
Name some complications of UC.
- Toxic megacolon
- Colorectal carcinoma
- Osteoporosis
- Pouchitis
