An appraisal of a 'string test' for the detection of small bowel bacterial overgrowth

The efficacy of a string test for the detection of small bowel bacterial overgrowth (SBBO) was determined by comparison with a sterile endoscopic method for sampling small bowel secretions in 15 subjects investigated for SBBO. Clinical value was found to be limited by poor sensitivity, specificity and positive predictive value. The string test is not an adequate substitute for oro-duodenal intubation for the detection of SBBO.