Week 2

Question 1

What are some of the unique features of mucosal immunity?

Answer 1

Anatomically closely related mucosal epithelium and lymphoid tissue, activated memory T cells and regulatory t cells,

ACTIVE down regulation of immune response, inhibiting macrophages and dendritic cells. So dont create a response to everything we eat

Question 2

What is a peyers patch?

Answer 2

A lymphatic tissue that samples antigens from the lumen. First step of an immune response in gut

Question 3

Describe the anatomy of a peyers patch

Answer 3

Composed of M cells and enterocytes. The M cell has microvilli on its surface to allow more things to cross the cell. If the dendritic cells contained becomes activated then they will move to the mesenteric lymph nodes to undergo proper specialisation to then go the lamina propria

Question 4

What receptor must antibodies bind to enter the lumen of the gut from the lamina propria?

Answer 4

Poly-Ig receptor

Question 5

To which MHC class do the CD8+ t cells bind?

Answer 5

MHC I

Question 6

What is the function of IL-13 produced from Th2 cells?

Answer 6

Induces epithelial cell repair and increased mucus production

Question 7

What is the end result of Th1 effector functions?

Answer 7

Chronic inflammation and host damage due to macrophage activity

Question 8

What is the outcome of selective IgA deficiency in GI?

Answer 8

Inability to produce IgA is ok as it can be replaced with IgM that can also bind to the poly-Ig receptor to be excreted into the lumen

Question 9

Male adult presents with recurrent bacterial infections, particularly in his lungs, sinuses and ears. Upon bloods you discover that he has normal B cell count but has no immunoglobulins. What immunodeficiency is this?

Answer 9

CVID

Common variable immunodeficiency

Question 10

7 month old boy presents with infection, upon bloods you discover no presence of B cells and no immunoglobulins. Diagnosis? Why presenting at this age and not earlier?

Answer 10

XLA (x-linked agammaglobuliaemia)

As up until this point there was still maternal IgG but not it has been cleared

Question 11

Little girl 11 months presents with infection of staph aureus, a failure to thrive with skin abscesses and liver abscess. Onbloods you find presence of phagocytes but a lack of ROS. Diagnosis? Treatment?

Answer 11

CGD (chronic granulomatus disease)

Bone marrow transplant

Question 12

Baby boy of 3 weeks presents with chronic diarrhoea, oral candidiasis, and interstitial pneumonitis. Infection of fungi. On bloods you discover pneumocystis jirovecii. Diagnosis? Treatment?

Answer 12

SCID severe combined immunodeficiency

Haematopoietic stem cell transplant

Question 13

Women of 25 years present with malnutrition, stomach cramping on eating gluten, bloating, dermatitis herpetiformis, diarrhoea and nausea. What test would you use to confirm diagnosis?

Answer 13

IgA anti-tissue transglutaminase autoantibodies (Relying on they’ve eaten gluten for 6 weeks)

Coeliac disease

Question 14

Strangulation, shock, drugs and hyperviscosity can all cause what?

Answer 14

Ischaemia of the bowel

Question 15

Why are primary tumours of the intestines uncommon?

Answer 15

Because the epithelial are always shedding so even if problematic will be dead soon

Question 16

Young male presents with excruciating RIF pain progressively worsening from the morning. He is vomiting. Diagnosis?

Answer 16

Appendicitis

Question 17

Histological signs of coeliac?

Answer 17

Flattened epithelium

Question 18

Define intestinal failure

Answer 18

Inability to maintain nutrition or fluid in intestines

Question 19

What can cause chronic intestinal failure?

Answer 19

Crohns disease, short bowels, radiation therapy, dymotility due to myopathy, malabsorptive states from scleroderma or immunodeficiency

Question 20

What is considered a short small bowel?

Answer 20

Anything below 100cm

Normal being 200cm

Question 21

If someone has intestinal failure, what nutritional options are available? How is this given?

Answer 21

Parenteral nutrition

Usually through subclavian veins, internal jugular veins

Question 22

What can you use to assess nutritional status of patients?

Answer 22

MUST score

Albumin (plasma protein that if decreased then malnourished)
Transferrin (protein dropped in protein and iron deficiency)
Urinary creatine (excretion reflects muscle mass)
IGF1 (reduced in malnutrition and liver failure)

Question 23

Describe the physiology of refeeding syndrome

Answer 23

Body starts producing hormones like insulin that shifts metabolites in the body like synthesis of glycogen, fat and proteins in cells.

This needs ions, that are depleted in the body like potassium, magnesium and phosphorus. This can result in low minerals causing death

Question 24

What are the parameters required for the MUST score?

Answer 24

BMI
Unexplained weight loss
Acutely ill/ unable to eat 5 days

Question 25

What measurement can be used to estimate the height of a patient if they are too unable to stand?

Answer 25

Ulna radius

Question 26

How much dietary fibre is recommended a day?

Answer 26

30g

Question 27

What are the two types of fibre, what do they do? What are they found in?

Answer 27

Soluble; forms gels indicating siety and slows gastric emptying. Oats, fruits Insoluble; absorbs water and swells causing siety. Found in wholegrains, vegetables, beans and lentils

Question 28

What is the daily/ weekly recommendation of red and processed meat? What does it provide?

Answer 28

70g a day or 300g a week. Source of vit B12, protein and iron. BUT haem iron produces free radicals

Question 29

What is the daily recommendation of salt intake? What bacterial does salt promote growth of?

Answer 29

5g a day H. Pylori