Constipation affects people of all ages at least once in their life time. It is a common condition. Diagnosis usually involves detailed history of the condition from the patient about the signs and symptoms.
Tests and diagnostic procedures are usually not needed for diagnosis of constipation.
Diagnosis of constipation involves:-
Details of bowel habits
Patients should not be embarrassed or shy in describing their normal bowel habits and the changes experienced. Diagnosis is made from the significant change in the bowel habits. Details of ignoring urges to pass stool and inadequacy of time and privacy for passing stools are also asked.
Details of diet and lifestyle habits
The patient is asked to detail the amount of fibres (from fruits and vegetables and whole grains) that they get in their daily diet. Lack of fluids and increased amount of red meats, processed meats and canned foods also leads to increased risk of constipation
Details of medications and laxative use
Several medications may cause constipation as a side effect. Laxative abuse is also an important cause of constipation and needs to be detected while diagnosing constipation.
Criteria for constipation are included in the ROME criteria. This includes:-
Less than three bowel movements a week
Passage of hard stools in more than 25% of bowel motions
Sense of incomplete bowel movements in more than 25% of bowel motions
Excess straining in more than 25% of bowel motions
Necessitating digital manipulation to facilitate passage of stools
Physical examination involves examination for fecal or stool impaction. Abdomen is examined for abnormalities as well.
Neurological disorders or spinal disorders are examined as they may lead to delay in bowel transit time and constipation. Spinal cord injury, multiple sclerosis, Parkinson’s disease etc. has to be ruled out.
Blood tests may be advised to rule out other conditions. If inflammatory bowel disease or bowel cancer is suspected a colonoscopy or sigmoidoscopy is advised.
Psychiatric evaluation is made to detect underlying cause of constipation. Previous history of sexual abuse, violence, trauma, fear or unusual attitude towards bowel motions, depression and eating disorders have to be ruled out or detected.
Anorectal function tests
Anorectal function tests may be advised to detect increased muscle tone of the anus sphincter. Tests include Manometry for Hirschsprung’s disease and Electromyography for spastic pelvic floor dysfunction. Rectal mucosa may be taken for biopsy to examine for abnormalities.
Reviewed by April Cashin-Garbutt, BA Hons (Cantab)