Department of Medicine, Division of Gastroenterology, Kansas University Medical Center, Kansas City, Kansas, USA.
BMC Gastroenterol. 2010 Feb 22;10:23. doi: 10.1186/1471-230X-10-23.
Small intestinal bacterial overgrowth (SIBO) is a condition in which excessive levels of bacteria, mainly the colonic-type species are present in the small intestine. Recent data suggest that SIBO may contribute to the pathophysiology of Irritable bowel syndrome (IBS). The purpose of this study was to identify potential predictors of SIBO in patients with IBS.
Adults with IBS based on Rome II criteria who had predominance of bloating and flatulence underwent a glucose breath test (GBT) to determine the presence of SIBO. Breath samples were obtained at baseline and at 30, 45, 60, 75 and 90 minutes after ingestion of 50 g of glucose dissolved in 150 mL of water. Results of the glucose breath test, which measures hydrogen and methane levels in the breath, were considered positive for SIBO if 1) the hydrogen or methane peak was >20 ppm when the baseline was <10 ppm, or 2) the hydrogen or methane peak increased by 12 ppm when baseline was >or=10 ppm.
Ninety-eight patients were identified who underwent a GBT (mean age, 49 y; 78% female). Thirty-five patients (36%) had a positive GBT result suggestive of SIBO. A positive GBT result was more likely in patients >55 years of age (odds ratio [OR], 3.6; 95% confidence interval [CI], 1.4-9.0) and in females (OR, 4.0; 95% CI, 1.1-14.5). Hydrogen was detected more frequently in patients with diarrhea-predominant IBS (OR, 8; 95% CI, 1.4-45), and methane was the main gas detected in patients with constipation-predominant IBS (OR, 8; 95% CI, 1.3-44). There was no significant correlation between the presence of SIBO and the predominant bowel pattern or concurrent use of tegaserod, proton pump inhibitors, or opiate analgesics.
Small intestinal bacterial overgrowth was present in a sizeable percentage of patients with IBS with predominance of bloating and flatulence. Older age and female sex were predictors of SIBO in patients with IBS. Identification of possible predictors of SIBO in patients with IBS could aid in the development of successful treatment plans.
小肠细菌过度生长（SIBO）是一种主要发生在小肠的细菌水平异常升高的疾病，主要是结肠型物种。最近的数据表明，SIBO 可能导致肠易激综合征（IBS）的病理生理变化。本研究的目的是确定 IBS 患者中 SIBO 的潜在预测因素。
根据罗马 II 标准诊断为 IBS 的成年人，如果以腹胀和胀气为主，他们会进行葡萄糖呼气试验（GBT）以确定是否存在 SIBO。在饮用 50 克葡萄糖溶解在 150 毫升水中后，分别在基线、30、45、60、75 和 90 分钟时采集呼吸样本。如果 1）基线 <10ppm 时，氢气或甲烷的峰值>20ppm；或 2）基线 >or=10ppm 时，氢气或甲烷的峰值增加 12ppm，则葡萄糖呼气试验的结果被认为是 SIBO 阳性，该试验测量呼吸中的氢气和甲烷水平。
确定了 98 名接受 GBT 的患者（平均年龄 49 岁；78%为女性）。35 名患者（36%）的 GBT 结果阳性，提示存在 SIBO。>55 岁的患者（比值比 [OR]，3.6；95%置信区间 [CI]，1.4-9.0）和女性（OR，4.0；95% CI，1.1-14.5）的阳性 GBT 结果更有可能。氢在腹泻为主型 IBS 患者中更常见（OR，8；95% CI，1.4-45），甲烷是便秘为主型 IBS 患者中主要检测到的气体（OR，8；95% CI，1.3-44）。SIBO 的存在与主要肠型或同时使用替加色罗、质子泵抑制剂或阿片类镇痛药之间没有显著相关性。
在以腹胀和胀气为主的 IBS 患者中，SIBO 的发生率相当高。年龄较大和女性是 IBS 患者发生 SIBO 的预测因素。确定 IBS 患者中 SIBO 的可能预测因素有助于制定成功的治疗计划。
