Journal Article

Smelling the Diagnosis: The Electronic Nose as Diagnostic Tool in Inflammatory Arthritis. A Case-Reference Study

Tak, Paul P., Sterk, Peter J., Bos, Lieuwe D., Brinkman, Paul, Gerlag, Daniëlle M., Fens, Niki, Brekelmans, Marjolein P.

2016

Overview

To investigate whether exhaled breath analysis using an electronic nose can identify differences between inflammatory joint diseases and healthy controls. In a cross-sectional study, the exhaled breath of 21 rheumatoid arthritis (RA) and 18 psoriatic arthritis (PsA) patients with active disease was compared to 21 healthy controls using an electronic nose (Cyranose 320; Smiths Detection, Pasadena, CA, USA). Breathprints were analyzed with principal component analysis, discriminant analysis, and area under curve (AUC) of receiver operating characteristics (ROC) curves. Volatile organic compounds (VOCs) were identified by gas chromatography and mass spectrometry (GC-MS), and relationships between breathprints and markers of disease activity were explored. Breathprints of RA patients could be distinguished from controls with an accuracy of 71% (AUC 0.75, 95% CI 0.60-0.90, sensitivity 76%, specificity 67%). Breathprints from PsA patients were separated from controls with 69% accuracy (AUC 0.77, 95% CI 0.61-0.92, sensitivity 72%, specificity 71%). Distinction between exhaled breath of RA and PsA patients exhibited an accuracy of 69% (AUC 0.72, 95% CI 0.55-0.89, sensitivity 71%, specificity 72%). There was a positive correlation in RA patients of exhaled breathprints with disease activity score (DAS28) and number of painful joints. GC-MS identified seven key VOCs that significantly differed between the groups. Exhaled breath analysis by an electronic nose may play a role in differential diagnosis of inflammatory joint diseases. Data from this study warrant external validation.

• Publisher: Public Library of Science,Public Library of Science (PLoS)
• Subject: Active control / Adolescent / Adult / Aged / Arthritis / Arthritis, Rheumatoid - diagnosis / Asthma / Biology and Life Sciences / Breath Tests / Case-Control Studies / Chronic obstructive pulmonary disease / Control methods / Cross-Sectional Studies / Diabetes / Diagnosis / Diagnostic software / Diagnostic systems / Differential diagnosis / Discriminant analysis / Disease control / Electronic Nose / Electronic noses / Female / Gas chromatography / Gas Chromatography-Mass Spectrometry / Humans / Identification methods / Immunology / Inflammatory diseases / Innovations / Joint diseases / Lung cancer / Male / Mass spectrometry / Mass spectroscopy / Medical diagnosis / Medical equipment / Medicine / Medicine and Health Sciences / Metabolism / Metabolites / Middle Aged / Organic compounds / Patients / Physical Sciences / Physicians / Principal components analysis / Psoriatic arthritis / Research and Analysis Methods / Rheumatoid arthritis / Rheumatology / Scientific imaging / Sensitivity / VOCs / Volatile organic compounds / Volatile Organic Compounds - analysis / Young Adult