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

BackgroundPatients 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.ObjectiveTo evaluate the diagnostic yield of SBCE in patients with unexplained chronic abdominal pain.DesignWe 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.SettingTwo investigators independently searched studies from databases and analyzed the results.PatientsA total of 1520 patients from 21 studies were included.InterventionsSmall-bowel capsule endoscopy.Main Outcome MeasurementsPer-patient diagnostic yield, with 95% confidence intervals (CI), was evaluated by a random-effect model. Clear categorical analysis also was performed.ResultsThe pooled diagnostic yield of SBCE in patients with unexplained chronic abdominal pain was 20.9% (95% CI, 15.9%-25.9%), with high heterogeneity (I2 = 80.0%; P ＜ .001). Inflammatory lesions were the most common (78.3%) positive findings, followed by tumors (9.0%).LimitationsHeterogeneity among studies, retrospective design, variable chronicity of abdominal pain, and different previous examinations before SBCE.ConclusionSBCE 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.