Week 2 Flashcards
List 4 functions of mucosal tissue
Reproduction
Sensory activities
Food absorption
Gas exchange
What is the dominant antibody in the gut?
IgA (usually IgG elsewhere)
Which antibody takes over if the patient can’t make IgA?
IgM
What are intra-epithelial lymphocytes (IELs)?
CD8 +ve T cells which lie within the epithelial lining of the gut
Describe what is meant by intestinal failure
Where gut is no longer able to supply the hydration and nutritional needs of the body
Describe the 3 types/ levels of intestinal failure
1 - self-limiting, short term postoperative (most common) -(days to weeks)
2- Prolonged, associated with sepsis and metabolic complications, often related to abdominal surgery with complications
3 - long-term but stable
How would you treat Type 1 intestinal failure
- Fluids and electrolytes
- Parenteral nutrition if unable to tolerate foods and fluids
- Acid suppression (proton pump inhibitors/ ocreteotide)
- Alpha hyrdocycholecalciferol (to presevre magnesium)
What is a risk associated with insertion of lines for parenteral nutrition?
Due to the close proximity to the lungs, there is a risk of pneumothorax
Is bowel lengthening as a treatment of Type 3 intestinal failure used in adults or children?
CHILDREN
Which other type of transplant is a small bowel transplant usually given in combination with?
Liver transplant
Which vessel supplies the small bowel?
The superior mesenteric artery
Describe the outcomes of the three types of infarct to the small bowel
Mucosal infarct - There will be regeneration and mucosal integrity will be restored
Mural infarct - Repair and regeneration - fibrous stricture
Transmural - Gangrene and death if not sorted
What is ‘Meckel’s Diverticulum’
A slight bulge in the small intestine due to incomplete regression of the vitello-intestinal duct (an embryological remnant)
Secondary small bowel tumours are more common than primary tumours. Where do these secondary tumours commonly metastasise from?
Ovaries
Colon
Stomach
What are the three types of primary tumour that can occur in the small bowel?
Lymphomas
Carcinoid tumours
Carcinomas
What are the symptoms of appendicitis
Epigastric pain initially, RIF pain later
Vomiting
Fever possible
List possible consequences of appendicitis
Rupture
Abscess
Sepsis
Peritonitis
Which genes is coeliac disease associated with?
HLADQ2/HLADQ8
What component of gluten is the toxic agent?
GLIADIN
What do serology tests to investigate for coeliac disease look for?
IgA (deficiency - 10X more likely to have coeliacs)
Anti-TTG
Anti-gliadin antibodies
Anti-endomesial antibodies
What can malabsorption of fats do to stool?
Cause STEATORRHOEA (fat in the stool)
List the negative possible effects of malabsorption
Weight Loss Anaemia Abdominal Bloating Vitamin deficiencies Failure to thrive
What are ‘Peyer’s Patches’
The lymph nodes of the gut
What is the function of M cells within payer’s patches?
They provide maximum surface area for antigen absorption
What happens in the TH1 response to infection?
Macrophages and B cells are activated
What happens in the TH2 response to infection and which Interleukins are responsible?
- IgE production (IL 4)
- Recruitment and activation of eosinophils (IL-5)
- Recruitment of mast cells which produce histamine/ TNFa and MMCP (IL-3 and IL-9)
- Epithelial repair and production of mucus (IL- 13)
What are the two main receptors for the HIV virus?
CCR5 and CD4
List disorders associated with primary immunodeficieny
SCID
CVID
XLA
Selective IgA deficiency
Which mucosal disorder is associated with low IgG, IgA, IgM and IgE, causing recurrent sinopulmonary and GI infections?
CVID
Which mucosal disorder is x-linked and involves agammaglobulinaemia (No B cells!)
XLA
Which areas of the GI tract does Crohn’s disease most commonly affect?
terminal ileum and the proximal colon
What does Crohn’s disease cause?
Inflammation and deep eroding fissures
What is the important gene to Crohn’s disease?
NOD2
What area of the GI tract does ulcerative colitis affect?
The rectum and the colon
Would mucositis occurring post-chemotherapy be considered as acute or chronic intestinal failure?
Acute/ Short-term
Would short-gut syndrome be considered as acute or chronic intestinal failure?
Chronic/ Long-term
What length of bowel constitutes ‘Short-Bowel Syndrome’
Less than 200cm
List some of causes and impacts of malnutrition
Causes;
- Anorexia
- Dysphagia
- Infection
- Malabsorption
Impacts;
- Infections and sepsis
- Poor wound healing
- GI dysfunction
- Weight loss
- Reduced muscle strength and fatigue
- Reduced respiratory muscle strength causes an increase in the risk of chest infections
List some of the assessments for malnutrition
Mid arm circumference Biochemical assessments for; - Albumin - Transferrin - Vitamins E.t.c
What is meant by enteral tube feeding?
Delivery of feed via a tube into the stomach or duodenum or jejunum
What are the indications of use for enteral tube feeding?
Upper GI obstruction
Unconscious patients
Swallowing disorder
What is meant by parenteral nutrition?
Administration of nutrient solutions via a vein
What are the indications for use of parenteral nutrition?
Severe malabsorption e.g IBD Short bowel syndrome Motility disorders Severe malnutrition Intestinal fistulae
What is ‘MUST’ a screening tool for?
Malnutrition risk
List some specific diseases that can be associated with malabsorption
Coeliacs Disease
Crohn’s Disease
Whipple’s disease
e.t.c
What is Tropical Sprue?
Colonisation of the intestines by an infective agent
Where does B- oxidation occur?
In the mitochondrial matrix
What are the products of B-oxidation?
1 Acetyl CoA
1 FADH2
1 NADH and H+
1 Fatty Acyl CoA
Under what conditions would ketone bodies accumulate?
Starvation
Where does fatty acid synthesis occur?
In the liver
What substance is the major fatty acid synthesis precursor?
Malonyl CoA
What substances upregulate Acetyl CoA and which downregulate it?
Upregulate - Citrate - Insulin Downregulate - Glucagon - Adrenaline - AMP - Pamitoyl CoA
Where does the urea cycle occur?
In the liver
What is the catalyst which sits at the centre of the glycogen polymer and acts as the starting point for the glycogen polymer to be extended?
Glycogenin
Which interleukin is specifically involved in Crohn’s disease?
IL 12
What is meant by mucous membrane pemphigoid?
A group of autoimmune disorders that involve blistering lesions affecting mucous membranes
