GI Problems One: Luminal pathology

Question 1

If someone has diarrhoea for less than two weeks what is likely diagnosis?

Answer 1

Infection, improving within timeframe

Question 2

If someone develops diarrhoea over months, what excludes infection as a differential?

Answer 2

• History is too long in an otherwise fit and well person.
• Immunocompromised can be longer: / Exclude C.difficile in someone with recent antibiotics.

Question 3

What history questions do you ask for someone with diarrhoea?

Answer 3

• Consistency
• Frequency
• Appearance +/- blood

Question 4

What rules out coeliac disease?

Answer 4

Unlikely with bleeding

(villi destruction -> malabsorption and diarrhoea, no inflammation therefore no bleeding)

Question 5

What rules out irritable bowel syndrome?

Answer 5

• Unlikely when bowel habit is regular
• Bleeding unlikely
• Nocturnal diarrhoea - unlikely

Question 6

Lower abdominal cramps suggests pain in which organ?

Answer 6

Hindgut - colon

Question 7

Whats a common presentation of IBS?

Answer 7

Bleeding and diarrhoea

Question 8

When is bowel cancer uncommon?

Answer 8

Not usually in a young person unless family history of polyp syndrome

Question 9

Why do people with prolonged inflammation develop a normocytic anaemia?

Answer 9

Inflammation shuts down bone marrow and red cell production

Question 10

How does occult bleeding change heamatocrit?

Answer 10

• Acute bleeding can drop Hb without change in MCV
• Chronic bleeding can drop Hb but usually MCV also falls due to iron deficiency

Question 11

What does low albumin and high ferritin suggest?

Answer 11

Acute phase reaction

Question 12

Whats the two common types of inflammatory bowel disease?

Answer 12

Crohns disease
Ulcerative collitis

Question 13

What is crohns? Where does it occur? What makes it worse?

Describe its appearance.

Answer 13

• DISCONTINUOUS ‘skip lesions’ inflammation (TRANSMURAL; Ulcer-> penetrating ulcer with fissuring)
• Any part of GI
• Made worse by smoking.

Can appear as deep ulcers with cobblestone appearance. Granulomas may be present. Can be inflammatory, fistuling, stricturing, perianal.

Question 14

Can infection cause bloody diarrhoea?

Answer 14

Yes many can.

Question 15

What is ulcerative collitis? Where does it occur? What does it look like?

Answer 15

• Colon only
• Continuous inflammation from rectum
• Shallow ulceration of mucosa.
• Inflammatory

Smoking protects.

Question 16

How does the inflammatory component of crohns present?

Answer 16

• Colitis = Diarrhoea, bleeding
• Ileitis = Abdo pain, ~1hr post prandial
• Gastritis/duodenitis = dyspepsia

Question 17

What does stricturing in crohns result in?

Answer 17

• Abdo pain and distension
• Vomiting
• Bowels not opening

Question 18

What sorts of fistulas occur in crohns?

Answer 18

Fistula = An abnormal connection / tract between the gut and another organ / vessel

• SI -> Skin
• SI -> SI
• Rectum and vagina
• Oesophagus and trachea

Question 19

What perianal features can appear in crohns?

Answer 19

• perianal abscess
• Perianal fistula
• Anal fissure

Question 20

Whats the clinical feature of ulcerative collitis?

Answer 20

• Diarrhoea, bleeding
• Frequent bowel motions and urgency
• Abdo discomfort
• Fever, malaise, weight loss
• Raised ESR/CRP, platelets

Question 21

What are the phenotypes of crohns disease?

Answer 21

Fistulas
Structuring
Inflammatory
Perianal

Question 22

What can happen in UC if inflammation extends to the smooth muscle?

Answer 22

Toxic megacolon - arrested smooth colonic movement leads to progressive dilatation

Question 23

Whats the treatment of IBD in general?

Answer 23

• 5-ASA (mild antiinflam)
• Steroids
• Immunosuprresion
• Anti-tumour necrosis factor

Question 24

What are the principles of surgery? when it comes to IBD?

Answer 24

When medical treatment fails
= Resect diseased bowel i.e colectomy. Ileal resection

Treatment of bowel complications
- Bowel obstruction
- Perforation
- Fistula
- Abscess

In crohns no cure

Question 25

Where is B12 absorbed?

Answer 25

Terminal ilium therefore removal of the terminal ilium removes the specialised B12/IF receptors

Question 26

What is the role of bile salt malabsorption in inflammatory bowel disease?

Answer 26

• Reduced re-uptake of bile salts via enterhepatic circulation

= Bile salts loss
= Fat malabsorption and fatty diarrhoea (steatorrhoea)

Bile salts in colon irritate colon, stimulate water and electrolyte secretion = secretory diarrhoea.

Question 27

What is the likely source of rectal bleeding?

Answer 27

• Upper GI unlikely unless melaena.
• Lower GI tract: likely
• Outlet (heamorrhoids / fissure): fresh on paper, not likely to cause iron deficiency

Question 28

Describe the colours of stool blood and likely source:

Answer 28

Black: Melaena: Upper GI/SI

Bright red on paper: Perinal

Bright red mixed with stools: Left colon

Dark red - Proximal colon, distal to SI

Question 29

Whats the autoantibody in coeliacs?

Answer 29

• IgA tissue transglutaminase antibodies

Question 30

What are some potential causes of erratic bowel habit?

Answer 30

• Ceoliac
• Irritable bowel syndrome