What workup is recommended for an exacerbation (flare) of Ulcerative Colitis (UC)?

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From the Guidelines

For a flare in ulcerative colitis, the workup should include stool studies to rule out infectious causes, inflammatory markers, and complete blood count to assess for anemia or signs of inflammation, as well as consideration of flexible sigmoidoscopy or colonoscopy to evaluate disease extent and severity, as recommended by the most recent guidelines 1.

Key Components of Workup

  • Stool studies: C. difficile toxin, stool culture, ova and parasites to rule out infectious causes
  • Inflammatory markers: CRP, ESR, fecal calprotectin to assess the level of inflammation
  • Complete blood count to evaluate for anemia or signs of inflammation
  • Flexible sigmoidoscopy or colonoscopy to assess disease extent and severity, particularly if symptoms are severe or if there's a need to evaluate the response to treatment

Considerations for Imaging and Medication Levels

  • Abdominal imaging such as CT scan or plain radiographs if there are concerns for toxic megacolon or perforation
  • Medication levels should be checked if the patient is on biologics like infliximab or adalimumab to ensure therapeutic concentrations, as suggested by guidelines for managing ulcerative colitis 1

Importance of Comprehensive Approach

This comprehensive approach is crucial because symptoms of UC flares can mimic infectious colitis, and determining the true cause guides appropriate treatment. Identifying the extent and severity of inflammation helps tailor therapy, which may include escalation of 5-ASA medications, addition of corticosteroids, or consideration of biologics or immunomodulators depending on the clinical scenario, as outlined in recent consensus guidelines 1.

From the Research

Workup for a Flare in Ulcerative Colitis

When experiencing a flare in ulcerative colitis, a comprehensive workup is essential to assess the severity of the disease and guide treatment decisions. The following steps are recommended:

  • Clinical evaluation: Assess symptoms such as rectal bleeding, stool frequency, and abdominal pain to determine the severity of the flare 2, 3.
  • Endoscopic evaluation: Ileocolonoscopy with biopsy is the gold standard for diagnosing and assessing the severity of ulcerative colitis 2, 3.
  • Laboratory tests: Common laboratory blood test immune panel markers, such as high sensitivity C-reactive protein (hs-CRP), C-reactive protein to albumin ratio (CAR), and complete blood count (CBC) related parameters, can be useful in grading ulcerative colitis endoscopic severity 4.
  • Imaging studies: Abdominal computed tomographic (CT) scanning may be used to evaluate acute abdominal symptoms and assess disease extent 2.
  • Patient-reported outcomes: Rectal bleeding and stool frequency subscores can be used to identify patients in endoscopic remission 5.

Key Findings

  • The presence of rectal bleeding is a significant indicator of active disease, and its absence can identify patients with inactive disease 6, 5.
  • Stool frequency is also an important symptom, but its correlation with endoscopic activity is weaker than rectal bleeding 6, 5.
  • Laboratory markers such as hs-CRP and CAR can be used to assess disease activity and predict endoscopic severity 4.
  • Endoscopic evaluation remains the gold standard for diagnosing and assessing the severity of ulcerative colitis 2, 3.

Disease Assessment

  • The Mayo scoring system is a commonly used index to assess disease severity and monitor patients during therapy 2.
  • The Mayo endoscopic score (MES) can be used to evaluate endoscopic disease activity 4.
  • Disease extent and severity should be assessed to guide treatment decisions and predict patient prognosis 2, 3.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Ulcerative Colitis: Making the Diagnosis.

Gastroenterology clinics of North America, 2020

Research

Patient-Reported Outcomes and Endoscopic Appearance of Ulcerative Colitis: A Systematic Review and Meta-analysis.

Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association, 2019

Research

Clinical Parameters Correlate With Endoscopic Activity of Ulcerative Colitis: A Systematic Review.

Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association, 2019

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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