Volatile Organic Compounds in Exhaled Air as Novel Marker for Disease Activity in Crohnʼs Disease

Abstract

We showed that VOCs can separate healthy controls and patients with active CD and CD in remission in a real-life cohort. Analysis of exhaled air is an interesting new noninvasive application for monitoring mucosal inflammation in inflammatory bowel disease.

The potential of volatile organic compounds for the detection of active disease in patients with ulcerative colitis

“…Acetic acid is a short chain fatty acid produced by the fermentation of carbohydrates by several bacteria (especially within the Firmicutes phylum) and can therefore be related to changes in the gut microbiota during the inflammatory process . Remarkably, the discriminatory VOC profile for distinguishing active and inactive UC differed from the set found in active vs. inactive CD, though most VOCs in both studies are related to lipid peroxidation due to oxidative stress . This is in line with findings that,for example, microbial perturbations differ between UC and CD and supports that UC and CD should be considered as separate clinical entities.…”

“…Therefore, the SCCAI, C‐reactive protein (CRP) and faecal calprotectin were used for the assessment of disease activity. It is readily accepted that in the absence of endoscopy as gold standard, a stringent surrogate definition of active disease or remission is needed, which was based on the combination of the clinical activity index, CRP and faecal calprotectin . Active disease was defined by faecal calprotectin ≥250 μg/g, and remission by the combination of SCCAI <3 points and CRP <5 mg/L and faecal calprotectin <100 μg/g.…”

“…The chemical identification of the compounds was performed using retention time and mass spectrum. Spectrum recognition was performed using the National Institute of Standards and Technology (NIST) mass spectral library, looking at the similarity between recorded mass spectra and the library mass spectra …”

“…19,20 Recently, we identified a sensitive and specific profile consisting of 10 VOCs to diagnose active disease in adults patients with Crohn's disease. 21 In earlier studies, single VOCs like ethane and pentane, which are degradation products of lipid peroxidation, could differentiate between healthy controls and IBD patients, and furthermore, ethane showed correlation with both clinical and endoscopic disease activity in UC. 22,23 These single VOCs lack however specificity for IBD-related inflammation.…”

“…chronic obstructive pulmonary disease) have been found . Recently, we identified a sensitive and specific profile consisting of 10 VOCs to diagnose active disease in adults patients with Crohn's disease …”