乳果糖和葡萄糖呼气试验诊断肠易激综合征患者小肠细菌过度生长的比较。

Comparison of lactulose and glucose breath test for diagnosis of small intestinal bacterial overgrowth in patients with irritable bowel syndrome.

机构信息

Department of Super Specialty of Gastroenterology, Post Graduate Institute of Medical Education and Research, Chandigarh, India.

出版信息

Digestion. 2012;85(3):243-7. doi: 10.1159/000336174. Epub 2012 Mar 30.

DOI:10.1159/000336174

PMID:22472730

Abstract

BACKGROUND AND AIMS

Validity of the lactulose breath test (LBT) to diagnose small intestinal bacterial overgrowth (SIBO) has been questioned. Therefore, a study was planned to compare LBT with glucose breath test (GBT) to diagnose SIBO in irritable bowel syndrome (IBS) patients and controls.

METHODS

175 diarrhea-predominant IBS patients and 150 apparently healthy controls were enrolled. IBS was diagnosed according to Rome II criteria. Breath samples were collected every 10 min up to 180 min. Breath H₂ and CH₄ were measured using an SC MicroLyzer. SIBO was positive with a sustained increase in breath H₂ or CH₄ or both ≥10 ppm over a baseline value within <90 min in case of LBT and within <120 min in GBT.

RESULTS

SIBO was positive in 60/175 (34.3%) patients by lactulose and in 11/175 (6.2%) patients by GBT. In controls, LBT was positive for SIBO in 45/150 (30%) patients and in 1/150 (0.66%) patients by GBT. Positive LBT for SIBO was not significantly different in patients and controls; while using GBT, SIBO was significantly higher (p < 0.01) in patients as compared to controls. By using GBT as gold standard for SIBO, sensitivity, specificity, positive predictive value and negative predictive value of LBT in IBS patients was 63.6, 67.7, 11.7 and 96.6% respectively.

CONCLUSION

LBT is not a good test to discriminate SIBO in IBS patients from controls.

摘要

背景与目的

乳果糖呼气试验（LBT）诊断小肠细菌过度生长（SIBO）的有效性受到质疑。因此，本研究计划比较 LBT 和葡萄糖呼气试验（GBT）在诊断肠易激综合征（IBS）患者和对照者中的 SIBO。

方法

纳入 175 例腹泻型 IBS 患者和 150 例健康对照者。IBS 诊断符合罗马 II 标准。采集呼气样本，每 10 min 采集一次，共 180 min。使用 SC MicroLyzer 测量呼气 H₂和 CH₄。LBT 阳性标准为在 90 min 内基线值持续升高≥10 ppm的 H₂或 CH₄或两者；GBT 阳性标准为在 120 min 内基线值持续升高≥10 ppm的 H₂或 CH₄或两者。

结果

LBT 阳性 60/175（34.3%）例患者，阳性 11/175（6.2%）例患者；GBT 阳性 45/150（30%）例对照者，阳性 1/150（0.66%）例患者。LBT 阳性患者与对照者之间无显著差异；而 GBT 阳性患者显著高于对照者（p < 0.01）。以 GBT 为 SIBO 金标准，LBT 在 IBS 患者中的敏感性、特异性、阳性预测值和阴性预测值分别为 63.6%、67.7%、11.7%和 96.6%。