Constipation

Question 1

What are the general causes of constipation?

Answer 1

Poor diet +/- lack of exercise
Poor fluid intake/ dehydration
IBS
Age
Post-operative pain

Anorectal disease
Intestinal obstruction
Metabolic/endocrine
Drugs
Neuromuscular
Other causes: idiopathic slow transit, idiopathic megarectum/colon, psychological

Question 2

List Anorectal diseases associated with constipation

Answer 2

Anal or colorectal cancer
Fissures/strictures
Rectal prolapse
Mucosal ulceration
Pelvic muscle dysfunction/ levator ani syndrome

Question 3

List different types of intestinal obstruction that can cause constipation

Answer 3

Colorectal carcinoma
Stricture (Crohn's disease)
Pelvic mass (fetus, fibroids)
Diverticulosis (rectal bleeding is a commoner presentation
Pseudo-obstruction

Question 4

List metabolic/endocrine causes for constipation

Answer 4

Hypercalcaemia
Hypothyroidism (presents with other symptoms too)
Hypokalaemia
Lead poisoning

Question 5

List drugs that can cause constipation

Answer 5

Opiates
Anticholinergics (tricyclics)
Iron
Some antacids 
Diuretics
Calcium channel blockers

Question 6

List neuromuscular conditions associated with constipation?

Answer 6

Spinal or pelvic nerve injury (e.g. trauma, surgery)
Systemic sclerosis
Diabetic neuropathy