Small-bowel capsule endoscopy in patients with unexplained chronic abdominal pain: a systematic review.

BACKGROUND: Patients frequently consult primary care physicians and gastroenterologists when experiencing chronic abdominal pain. Although its diagnostic efficacy in these settings is uncertain, small-bowel capsule endoscopy (SBCE) has been used to evaluate the unexplained reasons for abdominal pain.

OBJECTIVE: To evaluate the diagnostic yield of SBCE in patients with unexplained chronic abdominal pain.

DESIGN: We performed a retrospective review of publications reporting the diagnostic yield of SBCE in patients with unexplained chronic abdominal pain and calculated the overall diagnostic yield.

SETTING: Two investigators independently searched studies from databases and analyzed the results.

PATIENTS: A total of 1520 patients from 21 studies were included.

INTERVENTIONS: Small-bowel capsule endoscopy.

MAIN OUTCOME MEASUREMENTS: Per-patient diagnostic yield, with 95% confidence intervals (CI), was evaluated by a random-effect model. Clear categorical analysis also was performed.

RESULTS: The pooled diagnostic yield of SBCE in patients with unexplained chronic abdominal pain was 20.9% (95% CI, 15.9%-25.9%), with high heterogeneity (I(2) = 80.0%; P ＜ .001). Inflammatory lesions were the most common (78.3%) positive findings, followed by tumors (9.0%).

LIMITATIONS: Heterogeneity among studies, retrospective design, variable chronicity of abdominal pain, and different previous examinations before SBCE.

CONCLUSION: SBCE provides a noninvasive diagnostic tool for patients with unexplained chronic abdominal pain, but the diagnostic yield is limited (20.9%). Among patients with positive findings, inflammatory lesions are the most common.