Ulcerative colitis is a relapsing and remitting inflammatory bowel disease frequently encountered in primary care. This article provides a summary of ulcerative colitis and a review of the available evidence for management.

Epidemiology and Risk Factors

• Ulcerative colitis most commonly presents between 15 and 30 years of age and is more common in industrialized nations, with a prevalence of 286 per 100,000 adults in the United States.^1,2

• Incidence is similar in men and women.³

• Risk factors include urban living; family history of ulcerative colitis; recent Salmonella, Clostridioides difficile, or Campylobacter infection; tobacco cessation; and soda consumption.^4,5

• Protective factors include history of appendectomy, active tobacco use, tea consumption, and having been breastfed as an infant.^4,5

Diagnosis

DIFFERENTIAL DIAGNOSIS

• Active Salmonella, Shigella, Escherichia coli, Yersinia, Campylobacter, or C. difficile infection should be ruled out using stool studies.¹

• Amebic dysentery should be considered if an appropriate travel or exposure history exists. Cytomegalovirus infection should be excluded in immunocompromised patients.¹

• Other causes of bloody diarrhea include ischemic colitis, Crohn disease, and colitis caused by medications or radiation. Non-bloody diarrhea can be caused by microscopic colitis, irritable bowel syndrome, celiac disease, or food intolerances.⁶

SIGNS AND SYMPTOMS

• The most common presenting symptom is bloody diarrhea. Other common symptoms include abdominal pain, tenesmus, and fecal urgency.^1,2

• Extraintestinal manifestations include arthropathies, erythema nodosum, pyoderma gangrenosum, uveitis, iritis, and primary sclerosing cholangitis. These may be present before the onset of gastrointestinal symptoms.^7,8

• Overall, extraintestinal manifestations are only 6% more common in patients with inflammatory bowel disease than in the general population and are more common with Crohn disease compared with ulcerative colitis.⁸

DIAGNOSTIC TESTING

• Lower endoscopy should be performed on all adult patients with suspected ulcerative colitis.^1,9

• Fecal calprotectin testing has a high negative predictive value and helps to differentiate inflammatory bowel disease from irritable bowel syndrome, but no serum biomarkers alone are sufficient for the diagnosis of ulcerative colitis.¹⁰ A normal fecal calprotectin level (100 mcg per g or less) in children virtually excludes the diagnosis of ulcerative colitis (100% negative predictive value; 95% CI, 98% to 100%). Therefore, in children with a negative fecal calprotectin test, endoscopy can be limited to those whose symptoms persist without another diagnosis.^9,11

• Bacterial stool culture, including C. difficile toxin assay and stool examination for ova and parasites, should be performed. Other tests, such as complete blood count, erythrocyte sedimentation rate, and measurement of C-reactive protein, may be useful but are nonspecific.¹

• Endoscopic evidence of continuous colonic inflammation starting at the rectum with confirmatory biopsies establishes the diagnosis of ulcerative colitis.¹

• Elevation in serial measurements of fecal calprotectin predicts relapse, whereas serial values in the normal range predict continued remission over time.¹²