Department of Pharmacology and Toxicology, NUTRIM School for Nutrition, and Translational Research in Metabolism, Maastricht University, Maastricht, The Netherlands.
Department of Gastroenterology and Hepatology, NUTRIM School for Nutrition, and Translational Research in Metabolism, Maastricht University Medical Center+, Maastricht, The Netherlands.
Aliment Pharmacol Ther. 2017 May;45(9):1244-1254. doi: 10.1111/apt.14004. Epub 2017 Feb 26.
To optimise treatment of ulcerative colitis (UC), patients need repeated assessment of mucosal inflammation. Current non-invasive biomarkers and clinical activity indices do not accurately reflect disease activity in all patients and cannot discriminate UC from non-UC colitis. Volatile organic compounds (VOCs) in exhaled air could be predictive of active disease or remission in Crohn's disease.
To investigate whether VOCs are able to differentiate between active UC, UC in remission and non-UC colitis.
UC patients participated in a 1-year study. Clinical activity index, blood, faecal and breath samples were collected at each out-patient visit. Patients with clear defined active faecal calprotectin >250 μg/g and inactive disease (Simple Clinical Colitis Activity Index <3, C-reactive protein <5 mg/L and faecal calprotectin <100 μg/g) were included for cross-sectional analysis. Non-UC colitis was confirmed by stool culture or radiological evaluation. Breath samples were analysed by gas chromatography time-of-flight mass spectrometry and kernel-based method to identify discriminating VOCs.
In total, 72 UC (132 breath samples; 62 active; 70 remission) and 22 non-UC-colitis patients (22 samples) were included. Eleven VOCs predicted active vs. inactive UC in an independent internal validation set with 92% sensitivity and 77% specificity (AUC 0.94). Non-UC colitis patients could be clearly separated from active and inactive UC patients with principal component analysis.
Volatile organic compounds can accurately distinguish active disease from remission in UC and profiles in UC are clearly different from profiles in non-UC colitis patients. VOCs have demonstrated potential as new non-invasive biomarker to monitor inflammation in UC.
为了优化溃疡性结肠炎（UC）的治疗，患者需要反复评估黏膜炎症。目前的非侵入性生物标志物和临床活动指数不能准确反映所有患者的疾病活动情况，也不能区分 UC 与非 UC 结肠炎。呼气中的挥发性有机化合物（VOCs）可能可预测克罗恩病的活动期疾病或缓解期。
研究 VOCs 是否能够区分活动期 UC、缓解期 UC 和非 UC 结肠炎。
UC 患者参与了一项为期 1 年的研究。每次门诊就诊时采集临床活动指数、血液、粪便和呼吸样本。纳入明确的有明确界定的活动期粪便钙卫蛋白>250 μg/g 和无疾病活动（简单临床结肠炎活动指数<3、C 反应蛋白<5 mg/L 和粪便钙卫蛋白<100 μg/g）的患者进行横断面分析。非 UC 结肠炎通过粪便培养或放射学评估得到证实。通过气相色谱飞行时间质谱和基于核的方法分析呼吸样本，以识别有区别的 VOCs。
共纳入 72 例 UC（132 份呼吸样本；62 份活动期；70 份缓解期）和 22 例非 UC 结肠炎患者（22 份样本）。11 种 VOCs 在独立的内部验证集中以 92%的敏感性和 77%的特异性预测活动期 vs. 缓解期 UC（AUC 0.94）。主成分分析可将非 UC 结肠炎患者与活动期和缓解期 UC 患者清楚地区分开来。
挥发性有机化合物可准确区分 UC 患者的活动期疾病与缓解期，UC 患者的特征谱明显不同于非 UC 结肠炎患者的特征谱。VOCs 有望成为监测 UC 炎症的新型非侵入性生物标志物。
