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Flashcards in Constipation Deck (37):
1

List four mechanisms of constipation.

Abnormal bowel peristalsis
Hard faeces
Bowel obstruction
Patient not able/willing to push

2

For each of the mechanisms below, list some causes of constipation:
Abnormal bowel peristalsis
Hard faeces
Bowel obstruction
Patient not able/willing to push

- Abnormal bowel peristalsis
IBS
Medications
Others: hypothyroidism, hypercalcaemia, hypokalaemia, diabetic neuropathy, multiple sclerosis, Parkinson’s disease
- Hard faeces
Lack of dietary fibre
Dehydration
- Bowel obstruction
Colorectal carcinoma
Sigmoid volvulus
- Patient not able/willing to push
Haemorrhoids
Anal fissure
Pelvic floor dysfunction

3

List some red flag symptoms that may suggest that the constipation has a sinister cause.

Severe constipation that’s unresponsive to treatment
Absolute constipation
Rectal bleeding, tenesmus or intermittent mucoid diarrhoea
Significant weight loss, iron deficiency anaemia, night sweats

4

Why is it important to ask about the time course of the constipation?

Chronic constipation – usually benign
Recent change – pathology

5

Describe the type of stools that will be passed in constipation caused by dehydration or a lack of dietary fibre.

Hard and lumpy

6

List some associated symptoms of constipation.

Weight loss, night sweats, fever
Diarrhoea
Tenesmus
Blood in stools
Bloating
Hypothyroid symptoms (cold intolerance, weight gain, reduced appetite)
Bone pains
Polyuria and polydipsia

7

What might intermittent diarrhoea with constipation suggest?

Young – IBS
Middle-aged – colorectal cancer
Elderly – diverticular disease

8

What is tenesmus and what does it indicate?

Sensation of having a desire to defecate, which is continuous and recurs frequently, with or without the production of significant amounts of faeces
Suggests that there is a persistent mass in the rectum

9

Why is it important to take note of any bone pains that the patient is complaining about?

This may indicate the presence of bone metastases, which can lead to hypercalcaemia, which, in turn, can cause constipation

10

List some major risk factors for constipation.

Past medical history of bowel disease, neurological disorders, back problems or endocrine disease
Family history of bowel disorders
Medications
Diet

11

List some hereditary disorders that are risk factors for constipation.

Familial adenomatous polyposis (FAP)
Hereditary non-polyposis colorectal cancer (HNPCC)
Peutz-Jeghers syndrome

12

List some classes of medication that are known for causing constipation.

Opiates
Calcium channel blockers
Iron supplements
Tricyclic antidepressants
Anticholinergics

13

List some features of the abdominal examination that could give clues about the aetiology of the constipation.

Virchow’s lymphadenopathy
Abdominal mass
Anal fissures or haemorrhoids
Mass on DRE
Lax anal tone

14

List some important blood tests that may be useful when investigating a patient with constipation.

FBC – colonic cancers can bleed causing anaemia
U&Es and calcium – check for hypokalaemia and hypercalcaemia
TFTs – check for hypothyroidism
Glucose and HbA1c – check glycaemic control to assess risk of diabetic neuropathy

15

FOBT is used as a screening test for colorectal cancer. Other than colorectal cancer, what else can give a positive FOBT?

Colonic angiodysplasia
Polyps
Haemorrhoids
Aspirin, warfarin etc.

16

Which cancers are the following tumour markers associated with:
CEA
CA19-9
CA125

- CEA
Colorectal cancer
- CA19-9
Pancreatic cancer
- CA125
Ovarian cancer

17

List and provide a brief description of the forms of imaging that may be used to investigate a patient with constipation.

Proctoscopy – visualise anus and rectum
Rigid sigmoidoscopy – visualise as far as the sigmoid colon
Flexible sigmoidoscopy – visualise as far as the splenic flexure and can take biopsies/resect polyps. Requires bowel prep and sedation
Colonoscopy – visualise as far as the ileocaecal valve
Virtual CT colonography – performed in patients who are unable to tolerate colonoscopy
Double contrast barium enema – rarely used now
OGD – if lower GI pathology is not found

18

Outline the treatment options available for constipation.

Lifestyle – increase fluid intake and dietary fibre
Bulk producers
Stool softeners
Osmotic laxatives
Peristalsis stimulants
Enemas

19

Give examples of the following types of laxative:
Stool softeners
Osmotic laxatives
Peristalsis stimulants

- Stool softeners
Liquid paraffin
Arachic oil enema
- Osmotic laxatives
Movicol
Lactulose
Magnesium salts
- Peristalsis stimulants
Senna
Glycerol suppositories
Bisacodyl

20

Describe the typical presentation of a patient with hypothyroidism.

Young woman with reduced frequency of bowel movements
Lethargy
Reduced appetite
Weight gain
Cold intolerance
Features of carpel tunnel syndrome

21

What is the most common cause of hypothyroidism in the UK?

Hashimoto’s thyroiditis (autoimmune)

22

Which antibodies are associated with Hashimoto’s thyroiditis?

Anti-thyroid peroxidase antibodies

23

Describe the typical presentation of a patient with hypercalcaemia.

Polyuria
Polydipsia
Aches and pains
Abdominal pain
Constipation
Low mood

24

What are the four main causes of hypercalcaemia?

Bone metastases
Myeloma
Primary and tertiary hyperparathyroidism
Vitamin D toxicosis

25

How can you differentiate between myeloma and bone metastases as a cause of hypercalcaemia?

Myeloma has normal ALP because it activates osteoclasts and inhibits osteoblasts
Osteoblasts produce ALP

26

Describe the action of PTH.

Increase calcium and phosphate release from bone
Increase renal excretion of phosphate

27

In a hypercalcaemic patient, why is it abnormal to find a serum PTH that is within the normal range?

If calcium is high, PTH should be low because of negative feedback

28

List some causes of hyperparathyroidism.

Parathyroid adenoma
Parathyroid hyperplasia
Parathyroid carcinoma
PTH-secreting tumour
NOTE: PTHrP (PTH-related protein) can be secreted ectopically by some tumours

29

Describe the effect of vitamin D on the GI tract.

Increase calcium and phosphate reabsorption

30

Will the PTH be low, normal or high in a patient with vitamin D toxicosis?

Low

31

List some clinical features of bowel obstruction.

Abdominal distension
Tinkling bowel sounds
Absolute constipation
Colicky abdominal pain
Nausea and vomiting

32

What is considered an abnormal diameter of the:
Small bowel
Large bowel
Colon

Small bowel - 3 cm
Large bowel - 6 cm
Colon - 9cm

(rule of 3,6,9)

33

What are the distinguishing features of the small bowel and large bowel on an abdominal X-ray?

Small Bowel – valvulae conniventes
Large Bowel – haustra

34

What radiological sign is associated with sigmoid volvulus?

Coffee bean sign

35

What is Rigler’s sign?

When the wall of the bowel is particularly defined due to the presence of air on both sides of the wall
This is caused by bowel perforation causing gas to leak into the peritoneal cavity
It is also called double-wall sign

36

Outline the management of a patient with bowel obstruction.

‘Drip and Suck’
Nil by mouth to aspirate stomach contents
IV fluids

37

How is a sigmoid volvulus relieved?

A flatus tube is inserted to untwist and decompress the volvulus