alimentary immune functions

Question 1

3 symptoms of irritable bowel syndrome

Answer 1

recurrent abdominal pain, abnormal bowel motility, constipation/diarrhoea

Question 2

how is irritable bowel syndrome (functional disorder) different to inflammatory bowel disease

Answer 2

inflammatory bowel disease also contains inflammation, ulcers and other damage

Question 3

what type of abdominal pain is experienced in irritable bowel syndrome

Answer 3

visceral hypersensitivity

Question 4

what is visceral hypersensitivity

Answer 4

sensory nerve endings in intestinal wall have abnormally strong response to stimuli (e.g. stetching after meal)

Question 5

why do sufferers of irritable bowel syndrome have abnormal bowel motility

Answer 5

unabsorbed short-chain carbohydrates (lactose, fructose) act as solutes, drawing water into lumen, triggering visceral hypersensitivity and causing smooth muscles to spasm, creating diarrhoea if excess water not reabsorbed

Question 6

how else might spasms or pain be caused in irritable bowel syndrome

Answer 6

unabsorbed short-chain carbohydrates metabolised by gastrointestinal bacterial flora, creating gas which causes spasms or pain

Question 7

2 risk factors of irritable bowel syndrome

Answer 7

having had gastroenteritis (norovirus, rotavirus), stress

Question 8

4 treatments of irritable bowel syndrome

Answer 8

diet modification, constipation, spasms and pain, management of stress, anxiety, depression

Question 9

how is diet modified in irritable bowel syndrome

Answer 9

avoid certain foods with short-chain carbohydrates e.g. apples, beans, cauliflowers

Question 10

how is constipation treated in irritable bowel syndrome

Answer 10

soluble fiber, stool softeners, osmotic laxatives

Question 11

how are spasms and pain treated in irritable bowel syndrome

Answer 11

anti-diarrhoeals (serotonin antagonists), anti-muscarinic

Question 12

3 symptoms of coeliac disease

Answer 12

abdominal distension (bloating), diarrhoea, sometimes dermititis herpetiformis

Question 13

in coeliac disease, what is not broken down in the stomach

Answer 13

gliadin (33 amino acid peptide component of gluten)

Question 14

fate of gliadin in coeliac disease

Answer 14

reaches small intestine and binds to secretory IgA in mucosal membrane

Question 15

fate of gliadin-secretory IgA complex

Answer 15

binds to transferrin receptor (TFR) and transferred to lamina propria

Question 16

what cuts of the amide group from the protein

Answer 16

enzyme tissue transglutaminase (tTG)

Question 17

fate of deamidated gliadin

Answer 17

phagocytosed by macrophages and presented by MHC class II, causing destruction of epithelial cells due to activation of immune system

Question 18

2 methods of diagnosis of coeliac disease

Answer 18

antibody blood tests (anti-gliadin, anti-tTG, anti-endomysial (EMAs)); biopsy test of duodenum

Question 19

2 methods of dietary management of coeliac disease

Answer 19

gluten-free diet (wheat, barley, rye exclusion), medication

Question 20

what are factors affecting compliance in coeliac disease

Answer 20

lifestyle, eating out, cross contamination

Question 21

2 symptoms of Crohn’s disease

Answer 21

pain in affected area (normally right lower quadrant); diarrhoea and blood in stool

Question 22

what pathogens trigger Crohn’s disease

Answer 22

mycobacterium paratuberculosis, pseudomonas, listeria

Question 23

what does unregulated immune response in Crohn’s disease cause

Answer 23

destruction of cells in GIT

Question 24

what are responsible for development of Crohn’s disease

Answer 24

gene mutations e.g. frame-shift mutations in NOD2 gene

Question 25

what medications can be used to treat Crohn's disease

Answer 25

anti-inflammatory drugs, antibiotics

Question 26

what medication can be prescribed in severe Crohn's disease

Answer 26

immunosuppressants e.g. corticosteroids

Question 27

if other medical therapies are contraindicated, or surgery is used (remove tissue but not curing disease), what is recommended in Crohn's disease

Answer 27

liquid diet (nutritionally complete liquid feeds) along with corticosteroids

Question 28

what needs to be considered if using a liquid diet to treat Crohn's disease

Answer 28

type of feed, route, compliance, monitoring, assessment, refeeding syndrome risk

Question 29

progression from liquid diet in Crohn's disease

Answer 29

liquid diet to low fibre/low residue, then food reintroduction

Question 30

how to manage strictures in Crohn's disease to decrease obstruction, pain and gas production

Answer 30

change diet so that food can get through the stricture; as fibre can block the intestines, avoid fibrous parts of fruit and vegetables (skins, seeds, woody stalks), wholegrains, nuts, seeds, gristle and skin from meat and fish

Question 31

what can food intolerance test result in in Crohn's disease

Answer 31

food exclusion and nutritionally inadequate diets, as no evidence for intolerance

Question 32

2 symptoms of ulcerative colitis

Answer 32

pain in left lower quarant (due to ulcers along inner surface of large intestine); severe and frequent diarrhoea, sometimes with blood in stool

Question 33

mechanism of ulcerative colitis

Answer 33

autoimmune disorder whereby T cells destroy cells lining walls of large intestine

Question 34

secondary cause of ulcerative colitis

Answer 34

diet and stress

Question 35

what anti-inflammatory drugs are used to treat ulcerative colitis

Answer 35

sulfasalazine, mesalamine

Question 36

immunosuppressant drugs prescribed if ulcerative colitis is severe

Answer 36

corticosteroids, azathioprine, cyclosporine

Question 37

what can cure ulcerative colitis

Answer 37

colectomy (surgical removal of colon)

Question 38

what is used to minimise exacerbation of diarrhoea in ulcerative colitis

Answer 38

dietary manipulation

Question 39

why are pre/probiotics used in ulcerative colitis

Answer 39

treat and prevent pouchitis (when colon removed, leaving a pouch that becomes inflamed); help remission

Question 40

what may prebiotics cause in ulcerative colitis

Answer 40

abdominal pain, bloating, diarrhoea, flatulence

Question 41

dietary manipulation involved in treating diarrhoea in ulcerative colitis

Answer 41

drink fluid, nutritious drinks, replace salt; consume soluble fibre to help gut absorb more water from stool; avoid gas producing foods, high fibre or wholegrain cereals, alcohol (which worsens dehydration), caffeine and personal triggers

Question 42

3 symptoms of cholera infection

Answer 42

vomiting, nausea; abdominal pain; severe dehydration and diarrhoea (watery)

Question 43

how is Vibrio cholerae transmitted

Answer 43

through foecal-oral route through contaminated water and food

Question 44

mechanism of cholera getting into body if unvaccinated

Answer 44

bacteria reaches small intestine from stomach, where flagellum propels it towards epithelial cell; on making close contact it releases cholera toxin

Question 45

what does cholera toxin do in epithelial cell

Answer 45

starts a series of biochemical reactions resulting in exit of ions such as Na+, K+, Cl- and water

Question 46

diagnosis of cholera infection

Answer 46

stool test, to detect bacteria or antigen for the bacteria

Question 47

main treatment for cholera infection

Answer 47

drink lots of clean fluids and eat clean flood

Question 48

treatment for severe cholera infection

Answer 48

IV fluids, antibiotics