BACKGROUND:
With the introduction of new techniques to image the small bowel, there remains uncertainty about their role for diagnosing Crohn's disease.
OBJECTIVE:
To assess the sensitivity and specificity of capsule endoscopy (CE), CT enterography (CTE), ileocolonoscopy, and small-bowel follow-through (SBFT) in the diagnosis of small bowel Crohn's disease.
METHODS:
Prospective, blinded trial.
SETTING:
Inflammatory bowel disease clinic at an academic medical center.
PATIENTS:
Known or suspected Crohn's disease. Exclusion criteria included known abdominal abscess and non-steroidal anti-inflammatory drug (NSAID) use. Partial small-bowel obstruction (PSBO) at CTE excluded patients from subsequent CE.
INTERVENTIONS:
Patients underwent all 4 tests over a 4-day period.
MAIN OUTCOME MEASUREMENTS:
Sensitivity, specificity, and accuracy of each test to detect active small-bowel Crohn's disease. The criterion standard was a consensus diagnosis based upon clinical presentation and all 4 studies.
RESULTS:
Forty-one CTE examinations were performed. Seven patients (17%) had an asymptomatic PSBO. Forty patients underwent colonoscopy, 38 had SBFT studies, and 28 had CE examinations. Small-bowel Crohn's disease was active in 51%, absent in 42%, inactive in 5%, and suspicious in 2% of patients. The sensitivity of CE for detecting active small-bowel Crohn's disease was 83%, not significantly higher than CTE (83%), ileocolonoscopy (74%), or SBFT (65%). However, the specificity of CE (53%) was significantly lower than the other tests (P < .05). One patient developed a transient PSBO due to CE, but no patients had retained capsules.
LIMITATION:
Use of a consensus clinical diagnosis as the criterion standard-but this is how Crohn's disease is diagnosed in practice.
CONCLUSIONS:
The sensitivity of CE for active small-bowel Crohn's disease was not significantly different from CTE, ileocolonoscopy, or SBFT. However, lower specificity and the need for preceding small-bowel radiography (due to the high frequency of asymptomatic PSBO) may limit the utility of CE as a first-line test for Crohn's disease.