SAN DIEGO — A novel technique analyzing gaseous volatile organic compounds from samples of exhaled breath accurately detected tuberculosis among infected patients, according to a recent study.
Early diagnosis is one of the biggest challenges of TB management, according to Amandip Sahota, MD, from the University Hospitals of Leicester, United Kingdom. WHO estimated that 9 million people developed TB in 2013 and 1.5 million died from the disease, including 80,000 children. The current methods used to diagnosis patients rely on physicians’ clinical suspicion and diagnostic procedures that can be slow, expensive and require further expertise, the researchers said.
“A diagnostic test which gives rapid results, is low-cost, noninvasive and easy to use at the bedside anywhere in the world, is therefore a public health priority,” Sahota said in a press release.
The researchers assessed whether field asymmetric ion mobility spectrometry (FAIMS), a mobile device that can rapidly identify and separate complex odors, has the ability to detect TB in real time. They collected breath samples from 25 patients with confirmed TB. The patients provided the samples by exhaling into a 3L tedlar bag before or shortly after they started treatment. A FAIMS unit (Lonestar, Owlstone UK) measured the ionic mobility of gaseous volatile organic compounds within the patients’ samples. The results were processed within 2 hours using a previously developed analysis pipeline for FAIMS and were compared with control samples from 19 healthy participants. The accuracy of the process was estimated in a 10-fold cross-validation analysis.
The researchers reported that the gas analysis was more than 90% accurate in diagnosing pulmonary and extra-pulmonary TB, with a sensitivity of 93% and specificity of 94% (area under the curve = 0.96; 95% CI, 0.93-1).
“Although conducted in a small group of patients, these results show great promise and will form the basis for future research into breath analysis for TB detection,” Sahota said.
During a presentation, Sahota said the gas analysis will be applied to a larger cohort and other disease populations. The researchers will observe post-treatment outcomes and investigate the possibility of using a smaller device. – by Stephanie Viguers
Sahota A, et al. Breath Analysis to Diagnose Pulmonary and Extra-pulmonary Tuberculosis Using Ion Mobility Spectrometry. Presented at: Interscience Conference on Antimicrobial Agents and Chemotherapy; Sept. 17-21, 2015; San Diego.
Disclosure: Sahota reports no relevant financial disclosures.