Brainscape's Knowledge GenomeTM

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


See full index

semester 3 - gastrointestinal > 13. Large intestine and Inflammatory Bowel Disease > Flashcards

13. Large intestine and Inflammatory Bowel Disease Flashcards

1
Q

What are the functions of the large intestine?

A
  • Removes water from all the indigestible gut contents (proximal)
  • Turns chyme into a semi solid
  • Production of certain vitamins
  • Microbiome- contains lots of commensal bacteria
  • Acts as temporary storage until defaecation (distal)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What type of epithelium does the large intestine have?

A

Simple columnar

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

In which part of the colon is the faeces stored?

A

Transverse and descending colon

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

Where does the colonic mucosa derive fatty acids from and what are the by-products?

A

not from blood

Short chain fatty acids derived from the fermentation of dietary fibre
- The by-products of this fermentation process include CO2, methane and hydrogen gas

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

What is the relation of different parts of the colon to the peritoneum?

A
  • Ascending and descending colon are secondary retro peritoneal
  • Transverse colon has its own mesentery (transverse mesocolon)
  • Sigmoid colon has its own mesentery
  • Rectum:
  • Upper 1/3- intra-peritoneal
  • Middle 1/3 - retroperitoneal
  • Lower 1/3- no peritoneum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the arterial supply to the midgut component of the colon?

A

Superior Mesenteric Artery:

  • ilio-colic: caecum
  • right colic: ascending colon
  • middle colic: most transverse colon
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the arterial supply to the hindgut component of the colon?

A

Inferior Mesenteric Artery:

  • left colic: transverse colon and descending colon
  • sigmoid: descending colon and sigmoid colon
  • superior rectal: Upper 1/3 rectum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

At which vertebral level are the SMA and IMA given off?

A

L1 (trans-pyloric plane) and L3 respectively

- IMA given off slightly to the left

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Which arteires supply the lower 2/3rds of the rectum?

A
  • Middle rectal artery (from internal iliac)

- Inferior rectal artery (from internal pudendal artery from internal iliac)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the venous drainage of the midgut component of the colon?

A
  • Midgut drains into superior mesenteric vein
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the venous drainage of the hindgut component of the colon?

A
  • Hindgut drains into inferior mesenteric vein
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the venous drainage of the rectal component of the colon?

A
  • Upper 1/3 rectum drains into superior rectal vein

- Lower 2/3 rectum drains into system circulation via middle and inferior rectal veins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the difference in length between large and small intestine?

A
  • Large intestine much shorter (6 feet vs 20 feet)

* Large intestine is much wider (average 6cm vs 3cm)

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

Describe the longitudinal muscle layer of the colon?

A

External longitudinal muscle is incomplete

• Three distinct bands (teniae coli)

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

What are haustra and what are they due to?

A

Haustra are sacculations caused by contraction of teniae coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How much water is absorbed in the colon each day and what is absorption facilitated by?

A

Approx 1500 mls of water enter colon/day
• <100 mls excreted in faeces
•Facilitated by ENaC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

where does most of the water absorption occur in the colon and why?

A

proximal colon

Much tighter tight junctions
• Allows bigger gradient to form
• Less back diffusion of ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is inflammatory bowel disease and what are 2 common examples?

A

Group of conditions characterised by idiopathic inflammation of the GI tact
- Crohn’s disease and ulcerative colitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Describe the pattern in Crohn’s disease.

A
  • Affects anywhere in GI tract
  • terminal Ileum involved in most cases
  • Transmural
  • Skip lesions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Describe the pattern in Ulcerative colitis.

A
  • Begins in rectum
  • Can extend to involve entire colon (pancolitis)
  • Continuous pattern
  • Mucosal inflammation - not transmural
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are some extra-intestinal problems of Inflammatory bowel diseases?

A
  • MSK pain (up to 50%) e.g. Arthritis
  • Skin (up to 30%) e.g. Erythema nodosum /pyoderma gangrenosum /psoriasis
  • Liver/biliary tree e.g. Primary Sclerosing Cholangitis (PSC)
  • Eye problems (up to 5%)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are the causes of inflammatory bowel disease?

A
  • Genetic
  • Gut organisms (altered interaction)
  • Immune response
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are 2 genetic correlation with inflammatory bowel disease?

A
  • 1st degree relative increased risk

* Identical twins concordance 70%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are some possible triggers for immunological causes of IBD?

A

Antibiotics, Infections, Smoking, Diet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What age range do Crohn’s and UC typically affect?

A

2 peaks for each, about 20-25 and 50

- more common in 20s

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What are the signs and symptoms of Crohn’s?

A
  • loose, non-bloody stools
  • RLQ pain
  • some joint pains (lower limbs)
  • weight loss - reduced nutrient absorption
  • Tender mass (RLQ)
  • Mild perianal inflammation/ulceration
  • Low grade fever
  • Mildly anaemic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is the typical patient that will present with Crohn’s disease?

A
  • 22 year old female
  • 6/52 hx of 5x loose stools/day
  • Non bloody stools
  • Weight loss
  • Right lower quadrant pain
  • Some joint pains (lower limbs)
  • Smoker
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is the more likely explanation for mild anaemia in Crohn’s disease?

A

More likely due to the inflammation rather than any bleeding
- anaemia of chronic inflammation (MEH)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What type of oedema develops in Crohns?

A

Mucosal oedema

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is the gross appearance in Crohn’s?

A

skip lesion - Cobblestone appearance:

Inflammed mucosa with ulceration between

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

what can form in Crohn’s?

A
  • fistulas - inflammation go through transmural wall and connect with other parts of body
  • discrete superficial ulcers
  • deeper ulcers
  • strictures- transmural inflammation lead to fibrosis and narrowing of lumen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Describe the pattern in Crohn’s disease.

A
  • Affects anywhere in GI tract
  • terminal Ileum involved in most cases
  • Transmural
  • Skip lesions
33
Q

Describe the pattern in Ulcerative colitis.

A
  • Begins in rectum
  • Can extend to involve entire colon (pancolitis)
  • Continuous pattern
  • Mucosal inflammation - not transmural
34
Q

What are some extra-intestinal problems of Inflammatory bowel diseases?

A
  • MSK pain (up to 50%) e.g. Arthritis
  • Skin (up to 30%) e.g. Erythema nodosum /pyoderma gangrenosum /psoriasis
  • Liver/biliary tree e.g. Primary Sclerosing Cholangitis (PSC)
  • Eye problems (up to 5%)
35
Q

What are the causes of inflammatory bowel disease?

A
  • Genetic
  • Gut organisms (altered interaction)
  • Immune response
36
Q

What are 2 genetic correlation with inflammatory bowel disease?

A
  • 1st degree relative increased risk

* Identical twins concordance 70%

37
Q

What are some possible triggers for immunological causes of IBD?

A

Antibiotics, Infections, Smoking, Diet

38
Q

What age range do Crohn’s and UC typically affect?

A

2 peaks for each, about 20-25 and 50

- more common in 20s

39
Q

What are the signs and symptoms of Crohn’s?

A
  • loose, non-bloody stools
  • RLQ pain
  • some joint pains (lower limbs)
  • weight loss - reduced nutrient absorption
  • Tender mass (RLQ)
  • Mild perianal inflammation/ulceration
  • Low grade fever
  • Mildly anaemic
40
Q

What is the typical patient that will present with Crohn’s disease?

A
  • 22 year old female
  • 6/52 hx of 5x loose stools/day
  • Non bloody stools
  • Weight loss
  • Right lower quadrant pain
  • Some joint pains (lower limbs)
  • Smoker
41
Q

What is the more likely explanation for mild anaemia in Crohn’s disease?

A

More likely due to the inflammation rather than any bleeding
- anaemia of chronic inflammation (MEH)

42
Q

What type of oedema develops in Crohns?

A

Mucosal oedema

43
Q

What is the gross appearance in Crohn’s?

A

Cobblestone appearance:

Inflammed mucosa with ulceration between

44
Q

Where can fistula form in Crohn’s?

A

Between the bowel and: bowel, bladder, vagina, skin

45
Q

What is pathognomonic in Crohn’s disease histology (that can differentiate it from UC)?

A

presence of granulomas (organised collection of epithelioid macrophages)

46
Q

How is Crohn’s investigated?

A
  • Bloods e.g. Anaemia
  • CT /MRI scans e.g. Bowel wall thickening, obstruction, extramural problems
  • Barium enema/follow through e.g. strictures/fistula
47
Q

which gross pathological changes of Crohn’s can be seen in endoscopy?

A

skip lesions
cobblestone appearance
fistula
stricture

48
Q

What are the signs and symptoms of UC?

A
  • Loose, bloody stools, with mucus
  • Mild lower abdominal pain/cramping
  • painful red eye (ocular complications)
  • mild tender abdomen
  • no perianal disease (ulceration/fistula)
  • normal temp
49
Q

What is the typical patient that will present with UC, what will they complain of?

A
  • 25 year old female
  • 8/52 hx 10 x bloody stools/day
  • Mucus in stools
  • Weight loss
  • Mild lower abdominal pain/cramping
  • Painful red eye
50
Q

How does UC affect crypts in colon and lamina propria?

A 
• Crypt abscesses (neutrophilic exudate in crypts)
• Crypt distortion:
- Irregular shaped glands with dysplasia
- Darker crowded nuclei 
• reduced numbers of goblet cells

Also get Chronic inflammatory infiltrate of lamina propria

51
Q

Why might pseudopolyps form in UC?

A

Can develop after repeated episodes
• Inflammation then healing
• Non neoplastic
• More common in UC (vs Crohn’s

52
Q

How does the colon appear on imaging in UC?

A

Edges may look smoother, loss of haustra (sacculations)

53
Q

How is UC investigated?

A
  • Bloods: Anaemia, Serum markers
  • Stool cultures
  • Colonoscopy
  • Plain abdominal radiographs
  • Barium enema (mild cases only)
  • CT/MRI: Less useful in diagnosing uncomplicated UC
54
Q

What is the overlap in presentation of Crohns and UC called?

A

Indeterminate colitis (10% of IBD)

55
Q

compare the following distinguishing feature of crohn’s and UC:
location

A

Crohn’s - Anywhere in GI tract

UC - rectum/colon

56
Q

compare the following distinguishing feature of crohn’s and UC:
rectal involvement

A

Crohn’s - No

UC - Yes

57
Q

compare the following distinguishing feature of crohn’s and UC:
gross bleeding

A

Crohn’s - 25%

UC - Yes

58
Q

compare the following distinguishing feature of crohn’s and UC:
perianal disease

A

Crohn’s - 75%

UC - Rare

59
Q

compare the following distinguishing feature of crohn’s and UC:
fistula formation

A

Crohn’s - Yes

UC - No

60
Q

compare the following distinguishing feature of crohn’s and UC:
Malnutrition

A

Crohn’s - Potential

UC - No

61
Q

compare the following pathological feature of crohn’s and UC:
transmural inflammation

A

Crohn’s - Yes

UC - Rare

62
Q

compare the following pathological feature of crohn’s and UC:
granulomas

A

Crohn’s - upto 75%

UC - No

63
Q

compare the following pathological feature of crohn’s and UC:
fibrosis

A

Crohn’s - common

UC - No

64
Q

compare the following pathological feature of crohn’s and UC:
crypt abscesses

A

Crohn’s - rare

UC - Yes

65
Q

compare the following endoscopic feature of crohn’s and UC:

mucosal involvement

A

Crohn’s - skip lesions

UC - continuous

66
Q

compare the following endoscopic feature of crohn’s and UC:

aphthous ulcers

A

Crohn’s - yes

UC - rare

67
Q

compare the following endoscopic feature of crohn’s and UC:

linear ulcers

A

Crohn’s - yes

UC - rare

68
Q

compare the following endoscopic feature of crohn’s and UC:

friable mucosa

A

Crohn’s - rare

UC - Yes

69
Q

compare the following endoscopic feature of crohn’s and UC:

cobblestone appearance

A

Crohn’s - yes

UC - no

70
Q

compare the following endoscopic feature of crohn’s and UC:

fistula

A

Crohn’s - yes

UC - no

71
Q

compare the following endoscopic feature of crohn’s and UC:

narrowing

A

Crohn’s - yes

UC - rare

72
Q

What is the string sign of kantour?

A

Marked stricture seen with a barium follow through crohn’s

73
Q

what radiological feature is seen in double contrast enema of UC?

A
  • Lead pipe colon
  • Continuous lesions without skipping
  • Whole colon
  • Mucosal inflammation
74
Q

What is a lead pipe colon?

A

Featureless descending and sigmoid colon
• Lacking haustral markings
- seen with contract enema or other imaging modalities

75
Q

What type of appearance does UC give with continuous mucosal inflammation?

A

Granular appearance

76
Q

What are medical treatments for IBD?

A 
Stepwise approach
1. Aminosalicylates
◦ Sulfasalazine (5-ASA preparations), 
◦ For flares and remission
2. Corticosteroids
◦ Prednisolone, 
◦ for flares only
3. Immunomodulators
◦ Azathioprine (inhibits purine synthesis), 
◦ Fistulas/ maintenance of remission
77
Q

When are surgical treatments done for Crohns?

A

• Not curative
Done when there are strictures or fistulas
• As little bowel removed as possible - reduce absorptive surface
Can result in adhesions

78
Q

When are surgical treatments done for UC?

A

Curable (colectomy)
• Inflammation not settling
• Precancerous changes
• Toxic megacolon

semester 3 - gastrointestinal (17 decks)

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