Constipation
Overview
Constipation is commonly a result of poor diet and sedentary lifestyle, however it may also signal underlying gastrointestinal or non-gastrointestinal pathology. History-taking can aid in dividing these differential diagnoses and narrowing in on a cause.
Aetiology
Causes of Constipation
Primary
- Functional Constipation
Colorectal
- Faecal impaction
- Colorectal cancer
- Strictures - diverticular disease, ischaemia, IBD, radiation
- Volvulus
- Prolapse - rectocoele, enterocoele
- Anorectal disorders - fissure, fistula, ulcer, large haemorrhoids
- Motility disorders - slow transit bowel, irritable bowel syndrome
Non-Colorectal
- Lifestyle factors - poor diet, physical inactivity, increased age
- Medications - opioids, NSAIDs, ondansetron, anticholinergics, diuretics, antiepileptics, antacids, iron supplements, calcium supplements, calcium channel blockers
- Metabolic / endocrine - hypercalcaemia, hypokalaemia, uraemia, diabetes, hypothyroidism
- Neurological - stroke, Parkinson’s disease, MS, spinal cord trauma, Hirschprung disease
- Connective tissue disorders - amyloidosis, scleroderma
- Psychogenic - anxiety, depression, anorexia nervosa
- Pregnancy
History of Presenting Complaint
Stools
- The colour and consistency of the patient's stools.
Onset
- Whether the constipation started suddenly or gradually, and in what situation.
Timing
- Frequency of stools, and whether the patient passes any normal or loose stools between episodes of constipation.
Associated Symptoms
Whether the constipation is associated with any other symptoms.- Abdominal painNonspecific feature of many GI causes
- Sharp anorectal pain on passing stoolsSuggestive of anal fissure
- Abdominal BloatingSuggestive of irritable bowel syndrome
- Blood stained stoolsRed flag for colorectal cancer, diverticulitis or IBD
- Blood on toilet paperSuggestive of haemorrhoids or anal fissure
- Episodes of incontinenceSuggestive of overflow incontinence secondary to obstruction
- Weight lossRed flag for colorectal cancer
- Faeculant vomitingSerious indicator of bowel obstruction
Exacerbating Factors
- Whether there is anything that makes the consipation worse.
Alleviating Factors
- Whether there is anything that improves the constipation, and whether they have had any improvement with apperients.
Extra Credit
The Rome III criteria are used for the diagnosis of functional constipation. The criteria must be present for the last three months, with symptom onset at least 6 months prior to diagnosis.
Rome III Criteria
Diagnostic Criteria - ≥2 present
- Straining while defaecating at least 25% of defaecations
- Lumpy or hard stools at least 25% of defaecations
- Sensation of incomplete evacuation for at least 25% of defaecations
- Sensation of anorectal obstruction or blockage for at least 25% of defaecations
- Need for digital maneuvers to evacuate stool at least 25% of defaecations
- Less than three defaecations per week
Additional Criteria
- Loose stools rarely present without the use of laxatives
- Insufficient criteria to indicate irritable bowel syndrome
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