Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

module 104 - theme 1 > coeliac disease & IBS > Flashcards

coeliac disease & IBS Flashcards

1
Q

what is coeliac disease?

A
  • gluten sensitive enteropathy or coeliac sprue
  • an auto-immune mediated disease of the small intestine triggering by the ingestion of gluten in genetically predisposed individuals leading to malabsorption with cessation of symptoms on a gluten free diet
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is gluten composed of?

A
  • protein compound of wheat, rye and barley which is left behind after washing off the starch
  • gluten consists of gliadin and glutenins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what are the genetic abnormalities of coeliac disease?

A
  • associated with HLA-DQ2 and HLA-DQ8 in 95% and 5% of the patients respectively
  • the genes are located on Chronic 6p21
  • it has a strong hereditary predisposition affecting around 10% of first degree relatives
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

how does gluten cause coeliac disease?

A

1) gluten in wheat + small bowel mucosa
2) tissue transglutiminase
3) diamidates glutamine in gliadin
4) negatively charged protein
5) IL-15
6) natural killer cells + intraepithelial T lymphocytes
7) tissue destruction + villous atrophy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what are the symptoms of coeliac disease?

A
  • flat mucosa does not absorb nutrients and leads to symptoms of coeliac disease
  • asymptomatic coeliac disease: detected by blood test
  • classical coeliac disease
  • atypical coeliac disease
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what are the gastrointestinal symptoms of classic coeliac disease?

A
  • diarrhoea: smelly & bulky stool, rich in fat
  • flatulence
  • borborygmus
  • weight loss
  • children fail to thrive
  • weakness & fatigue
  • severe abdominal pain
  • irritable bowel like symptoms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what are the extra-intersisital symptoms of atypical coeliac disease?

A
  • anaemia
  • osteopenia and osteoporosis
  • muscle weakness, pins and needles, loss of balance
  • itchy skin conditions
  • lack of periods, delayed periods in teenagers
  • infertility in women
  • impotence and infertility in men
  • bleeding disorders due to vitamin K deficiency
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what investigations are done for coeliac disease?

A
  • FBC, U&E, LFTs
  • tissue transglutaminase IgA
  • endomysial IgA; connective tissue covering the smooth muscle fibres
  • deaminated gladden peptide IgA & IgG
  • for monitoring compliance to gluten free diet
  • zero-negative coeliac disease
  • HLA DA2 and HLA DQ8 in children with positive TGA and symptoms to avoid biopsies
  • duodenal biopsies
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

how do coeliac tests work?

A
  • assess tissue damage
  • when the small bowel is exposed to gluten there is an overreaction of the immune system to produce antibodies to the proteins involved in tissue damage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what are the microscopic features of coeliac disease?

A
  • villus atrophy (VA)
  • crypt hyperplasia
  • increase in lymphocytes in the lamina propria/chronic inflammation
  • increase in intraepithelial lymphocytes (IEL)
  • recovery of villous atrophy on gluten-free diet
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what are the complications of coeliac disease?

A
  • enteropathy associated T-cell lymphoma
  • high risk of adenocarcinoma of small bowel, and other organs (large bowel, oesophagus, pancreas)
  • may be associated with dermatitis hepeiformis
  • infertility and miscarriage
  • refractory coeliac disease despite strict adherence to gluten free diet
  • gluten free diet mat reduce risk of complications
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what constitutes inflammatory bowel disease?

A
  • Crohn’s disease
  • ulcerative colitis
  • diverticular disease
  • ischaemic colitis
  • drug included colitis (NSAIDs)
  • infective colitis
  • CD and UC = collectively known as idiopathic inflammatory disease (IBD)
  • some overlap in aetiology, clinical presentation, morphological features and treatment
  • important to distinguish CD from UC because of different complications of different surgical procedures
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is Crohn’s disease?

A

an idiopathic, chronic inflammatory bowel disease often complicated by fibrosis and obstructive symptoms and can affect any part of the GIT from mouth to anus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what religion has a high risk of Crohn’s disease?

A

Judaism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what causes Crohn’s disease?

A
  • the exact cause is unknown
  • genetic, infectious, immunological, environmental, dietary, vascular, smoking NSAIDs and psychological factors have all been implicated
  • defects in mucosal barriers which allow pathogens and other antigens to induce an unregulated inflammatory reaction
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what are the genetics of Crohn’s disease?

A
  • strong scientific evidence for genetic predisposition to CD
  • first degree relatives have 13-18% increased risk of developing CD with a 50% concordance in monozygotic twins
  • no classicalmedelian inheritance but polygenic
  • NOD2 gene alsoCARD15 on Chr16 encodes a protein associated with to uncontrolled inflammatory response to luminal contents and microbes
17
Q

what doubles the risk of Crohn’s disease?

A

smoking

18
Q

what are the clinical features of Crohn’s disease?

A
  • chronic, indolent course punctuated by peirods of remission and relapses
  • abdominal pain, relieved by opening bowels
  • prolonged non-bloody diarrhoea
  • blood may be present is the colon is involved
  • loss of weight, low grade fever
19
Q

what is the distribution of Crohn’s disease?

A
  • affects any part of GIT from mouth to anus
  • small bowel alone = 40%
  • large bowel alone = 30%
  • small and large bowel = 30%
20
Q

what are the morphological features of Crohn’s disease?

A
  • fat wrapping of the serosa
  • involves the bowel in a segmental manner where normal bowel is separated by abnormal bowel to give risk to skip lesions
  • ulceration of the mucosa to give rise a cobblestone pattern
  • strictures due to fibrosis
21
Q

what are the microscopic appearance of Crohn’s disease?

A
  • transmural or full thickness inflammation of the bowel wall
  • mixed acute and chronic inflammation
  • preserved crypt architecture
  • mucosal ulceration
  • fissuring ulcers
  • granulomas present in 60-65%
  • fibrosis of the wall
22
Q

what are the complications of Crohn’s disease?

A
  • intra-abdominal assesses
  • deep ulcers lead to fistula = communications between 2 mucosal surfaces
  • sinus tract = blind ended tract ends in a ‘cul de sac’
  • obstruction due to adhesions
  • obstruction due to strictures caused by increased fibrosis
  • perianal fistula and sinuses
  • risk of adenocarcinoma but not as high in UC
23
Q

what is ulcerative colitis (UC)?

A

a chronic inflammation bowel disease which only affects the large bowel from the rectum to the caecum. unlike CD, the inflammatory process is confined to the mucosa and sub-mucosa except in severe cases

24
Q

who is ulcerative colitis more prevalent in?

A
  • Jews

- peaks between 20-25 years

25
Q

what causes ulcerative colitis?

A
  • cause is unknown
  • multiple factors are implicated
  • generic predisposition: high incidence in first degree relatives and high concordance in twins & HLA-B27 identified in most patients but not thought to be an aetiological factor
  • no specific infective agent has been identified
  • smoking actually protects so stopping smoking may trigger it
  • NSAIDs exacerbates it
  • antioxidants vitamins A and E are round in low levels
26
Q

what are the clinical features of ulcerative colitis?

A
  • intermittent attacks of bloody diarrhoea
  • mucoid diarrhoea
  • abdominal pain
  • low grade fever
  • loss of weight
27
Q

what are the macroscopic features of ulcerative colitis?

A
  • affects the large bowel from rectum to caecum
  • can affect rectum only, left sided bowel only or whole large bowel
  • despite the term ‘ulcerative’ there are no ulcers on endoscopic examination in early disease
  • diffuse mucosal involvement which appears haemorrhagic
  • with chronicity, the mucosa becomes flat with shortening of the bowel
28
Q

what are the microscopic features of ulcerative colitis?

A
  • inflammation confined to the mucosa
  • diffuse mixed acute and chronic inflammation
  • crypt architecture distortion
  • in quiescent UC, the mucosa may be atrophic with little or few inflammatory cells in he lamina proprietor
29
Q

what are the complications of ulcerative colitis?

A
  • complications invariable lead to surgety
  • refractory to medical treatment
  • toxic mega colon = bowel grossly dilated (patient very ill, bloody diarrhoea, abdominal distention, electrolyte imbalance with hypoproteinaemia)
  • refractory bleeding
  • dysplasia or adenocarcinoma in patients at risk
  • after 8-10 years of UC patient require annual screening colonoscopy
30
Q

what are the extra-intestinal manifestations of CD and UC?

A
  • ocular: uveitis, iritis, episcleritits
  • cutaneous: erythema nodosum, pyoderma, gangernosum
  • arthropathies: ankylosing spondylitis
  • hepatic: screlosing cholangitis
31
Q

what investigations do you do in CD and UC?

A
  • FBC
  • U&Es
  • LFTs
  • inflammatory markers - C reactive protein
  • faecal calprtectin
  • endoscopy and biopsies
  • radiological imaging: barium studies, MRI, USS and CT scan

module 104 - theme 1 (17 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions