Small Intestinal Bacterial Overgrowth in Patients with Irritable Bowel Syndrome: Clinical Characteristics, Psychological Factors, and Peripheral Cytokines

Figure 1

SIBO prevalence in IBS patients and healthy controls as determined by six published diagnostic criteria. Only Criterion 4 for the combined lactulose HBT/SOCT indicated a higher prevalence of SIBO in patients than controls (which has been published). Criterion 1: a H₂ rise of ≥20 ppm within 180 min; Criterion 2: a H₂ rise of ≥20 ppm within 90 min; Criterion 3: dual breath H₂ peaks, a 12 ppm increase in breath H₂ over baseline with a decrease of ≥5 ppm before the second peak; Criterion 4: initial H₂ rise, involving at least two consecutive values ≥5 ppm above baseline, commenced at least 15 min before an increase of radioactivity (≥5% of administered dose) in the caecal region; Criterion 5: initial H₂ rise, involving at least two consecutive values ≥10 ppm above baseline, commenced at least 15 min before an increase of radioactivity (≥5% of administered dose) in the caecal region; Criterion 6: initial H₂ rise, involving at least two consecutive values ≥20 ppm above baseline, commenced at least 15 min before an increase of radioactivity (≥5% of administered dose) in the caecal region; .