Lung cancer and airway infections gain increasing importance. Early diagnosis is desirable. We examined if volatile metabolites occurring in human exhaled air can be correlated directly to different kinds of diseases.
An ion mobility spectrometer (IMS) coupled to a multi-capillary-column (MCC) was used to identify and quantify volatile metabolites occurring in human breath down to the ng/L- and pg/L-range of analytes within less than 500 s and without any pre-concentration. The IMS investigations are based on different drift times of swarms of ions of metabolites formed directly in air at ambient pressure.
During a pilot study data were obtained from 36 patients suffering with lung cancer and 54 healthy persons in a control group. A reduction from more than one million data points per IMS-chromatogram to 25 variables enabled a classification and differententiation of these two groups with an error of 1.3 %.In a further study IMS-chromatograms were obtained from 30 patients with different airway infections (COPD-exacerbations, bronchiectasis, pneumonia). In comparison to healthy persons typical clusters of bacterial metabolites could be found.
These first clinical data show, that ion mobility spectrometry allows precise detection of airway infections as well as a distinction of patients with lung cancer from healthy people with high accuracy.The preliminary data need further confirmation by studies with greater populations.
Ion mobility spectrometry seems to be a promising tool in the diagnostic approach to lung cancer and airway infections.
Michael Westhoff, None.