Clinical Evaluation

These features in a patient with constipation should prompt evaluation, e.g., with a diagnostic colonoscopy, for an underlying colorectal malignancy.

• Blood in stool

• Rectal bleeding

• Rectal tenesmus

• Clinically significant unintentional weight loss

• Unexplained iron deficiency anemia

• Jaundice

• Obstructive symptoms

• Patients > 50 years of age without previous screening for colorectal cancer; recent guidelines suggest 45 years as the cut-off to start screening

• Abdominal or rectal mass

• Sudden change in bowel habits (e.g., onset of constipation without clear cause, change in stool caliber)

• Family history of pertinent GI conditions (e.g., colorectal carcinoma, IBD)

A change in bowel habits (e.g., pencil-thin stool caliber) and/or rectal bleeding, especially in patients > 50 years of age, may indicate colorectal cancer and must be evaluated.

The Rome IV diagnostic criteria for primary constipation in adults are only applied if there is no suspected or identified cause of secondary constipation. All criteria must be present to establish a diagnosis. [7]

• Symptom onset ≥ 6 months prior

• The presence of ≥ 2 of the following symptoms in at least 25% of bowel movements over the last 3 months:

  • Passage of spontaneous stool < 3 times/week

  • Passage of hard or lumpy stool

  • Sensation of anorectal obstruction

  • Sensation of incomplete evacuation (rectal tenesmus)

  • Straining during attempts to defecate

  • Manual aid to evacuate stool

• Loose stools are rarely present except when laxatives are used.

• Rome IV criteria for irritable bowel syndrome are not met

Infrequent, hard stools (e.g., Bristol stool types 1 and 2) may suggest slow transit constipation. Straining and a sensation of incomplete evacuation may suggest a defecatory disorder.

A thorough physical examination should be performed, including the following:

• Abdominal examination to assess for GI pathology

• Inspection of perineum and anus

  • Evaluate for anal fissures and hemorrhoids.

  • Test the anal wink reflex: An absent anal wink reflex suggests a neurological pathology (e.g., sacral nerve injury).

  • Digital rectal examination

  • Check for masses (e.g., rectal carcinoma, fecal impaction, rectocele).

  • Assess anal sphincter tone and function for signs of pelvic floor dyssynergia.