Week 6- Inflammatory bowel disease aetiology+pathogenesis+symptoms and complications

Question 1

what is inflammatory bowel disease? types

Answer 1

its 2 inflammatory disorders of the gastro-intestinal tract
– Crohn’s Disease (CD)
– Ulcerative Colitis (UC)
both chronic diseases follows an unpredicatble relapsing and remitting

Question 2

what is crohns disease?

Answer 2

• Affects any part of the G.I. tract from mouth to rectum
• Inflammation extends through all layers of the gut wall
• inflammation is patchy in distribution

Question 3

what is ulcerative colitis?

Answer 3

• Affects the colon and rectum only
• Only affects the mucosa (and submucosa)
• inflammation is diffuse in distribution

Question 4

what is the epideiology for for IBD?

Answer 4

• more common in industrialised countries and affects races and both sexes
• can occur at any age, peak incidences occur between 10-40yrs

Question 5

what is the incidences for IBD?

Answer 5

ulcerative colitis is twice as common as crohn’s disease

Question 6

what is the aetiology of IBD?

Answer 6

• causative agent is unknown

- number of factors that play a role if environmental i.e. diet, smoking,infection, drugs and genetic

Question 7

how does diet affect IBD?

Answer 7

-high dairy, fat and low fruit and veg (westernised) and high fibre

Question 8

how does smoking affect IBD?

Answer 8

smoking may help to prevent the onset of UC as the chemicals affect colon smooth muscle, alters gut motility and transit time

Question 9

how does infections affect IBD?

Answer 9

-exposure to Mycobacterium
paratuberculosis can cause CD
-UC can occur after episode of infective diarrhoea
-association with measles and mumps infection

Question 10

how does enteric microflora affect IBD?

Answer 10

– IBD patients loss of immunological tolerance to intestinal microflora
-Can be manipulated by antibiotics, probiotics and prebiotics to balance favourably

Question 11

how does drugs affect IBD?

Answer 11

• NSAIDs can exacerbate IBD
• antibiotics can change enertic microflora cause relapse
• oral contraceptive pill, increase risk of developing CD
• isotretinoin risk

Question 12

how does having an appendectomy (removal of appendices) affect IBD?

Answer 12

-has a protective effect for UC and CD

Question 13

how does stress affect IBD?

Answer 13

-can trigger a relapse
-Activates inflammatory mediators at enteric nerve
endings in gut wall, leading to inflammation in the bowel

Question 14

how does genetic factors influence the risk of IBD?

Answer 14

• DISRUPTION IN EPITHEIAL BARRIER INTEGRITY
• deficits in autophagy (cell death)
• deficiencies in innate pattern receptors
• problems with lymphocytes differentiation especially CD

Question 15

what is the gene that is mutated in CD ?

Answer 15

NOD2 it is a inflammatory receptor

Question 16

which ethical group is more prone to IBD?

Answer 16

• jews

- is lower in non-white races

Question 17

what is the pathophysiology?

Answer 17

IBD is a servere, prolonged and inappropriate inflammatory response to trigger factors. Alter the normal structure of the GI tract.
Could be due to:
– Increased activity of effector lymphocytes & proinflammatory cytokines that override normal control mechanisms
– Primary failure of regulatory lymphocytes &
cytokines
– In CD, T cells are resistant to apoptosis after
inactivation

Question 18

what is the pathophysiology of CD?

Answer 18

• affects any part of the gut usually the terminal ileum and ascending colon and its discontinous
• affects areas are thickened, oedematous, and narrow. deep ulcers can appear, deeps fissuring ulcers, fibrosis
• Th1 associated

Question 19

what is the pathophysiology of UC?

Answer 19

• only affects mucosa and submucosa
• can affect just retum or left side colitis or whole colon
• starts in rectum
• mucosal ulceration
• mucosa looks red, inflammed and bleeds
• Th2 associated

Question 20

where does UC occur?

Answer 20

-lower bowel

Question 21

what are some clinical features, symptoms for both diseases?

Answer 21

– Diarrhoea		
– Fever	
– Abdominal	pain	
– Nausea	and	vomiting	(more	common	in	CD)	
– Malaise	
– Lethargy	
– Weight	loss	(more	common	in	CD)	
– Malabsorption		
– Growth	retardation	in	children

Question 22

what are some clinical features, symptoms present for CD?

Answer 22

• pain in lower right quadrant
• anaemia
• palpable masses (feeling a lump due to swelling
• small bowel obstructions
• fistulas
• gut perforation (formation of hole)

Question 23

what are some clinical features, symptoms present for UC?

Answer 23

• mainly diarrhoea possibly with blood/mucus
• abdominal pain
• constipation

Question 24

what are some distinguising features of CD vs UC?

Answer 24

-patchy= common in CD never in UC
-rectal sparing= common in CD never in UC
-

Question 25

how do complications occur of IBD?

Answer 25

-due to inflammation spilling over into other tissues

Question 26

where do complications with IBD occur?

Answer 26

• joint and bones= cause arhropathies and loss of bone
• skin= erthema nodosum which is tender, hot, red nodules which subside but leave discolouration or pustles develop ulcers
• eyes= burning red eyes, blurred vision
• liver= narrowing of the bile duct

Question 27

what is the morbidity for IBD?

Answer 27

• quality of life is generally lower in CD vs UC due to recurrences after surgery
• increased risk of cancer due to inflammation risk factor
• malnutrition and chronic anaemia common in long standing CD

Question 28

what kind of tests can be done for IBD diagnosed?

Answer 28

• biochemical
• endoscopic
• radiological
• histological-nuclear medicine based

Question 29

how can history of disease help IBD be diagnosed?

Answer 29

• recent travel
• medication
• smoking
• family history
• details of sympotoms like stool frequency, urgency, rectal bleeding, abdominal pain, fever

Question 30

what is the essential initial assessment that can be done?

Answer 30

• abdominal radiography
• tell you if there is any mass in the right iluem for CD
• helps assess disease extent in UC

Question 31

what other investigations can be done?

Answer 31

• sigmoidscopy= internal examination of the colon
• rectal biopsy
• colonscopy
• small bowel radiology
• ultrasound
• barium enema