January 11, 2013
Researchers Identify Respiratory Ailments Using Simple Breath Test
Lawrence LeBlond for redOrbit.com - Your Universe Online
Scientists said a simple breath test could diagnose infections in the respiratory system based on a study identifying the chemical ℠fingerprints´ that are given off by certain bacteria that are present in the lungs.
Publishing the new findings in today´s issue of the Journal of Breath Research, the researchers said they have successfully distinguished between different types of bacteria, as well as different strains of the same bacteria. Working with mice, they were able to analyze the volatile organic compounds (VOCs) present in exhaled breath.
"Traditional methods employed to diagnose bacterial infections of the lung require the collection of a sample that is then used to grow bacteria. The isolated colony of bacteria is then biochemically tested to classify it and to see how resistant it is to antibiotics,” said Hill in a statement.
"This whole process can take days for some of the common bacteria and even weeks for the causative agent for tuberculosis. Breath analysis would reduce the time-to-diagnosis to just minutes," she added.
Breath-testing would be an attractive method for diagnosis of lung infections due to its ease of use and non-invasiveness. Breath-testing has already seen some success in other medical avenues, such as diagnosis of certain cancers, asthma and diabetes.
The team infected mice with both bacteria and took breath samples after 24 hours of infection. The VOCs were analyzed using secondary electrospray ionization mass spectrometry (SESI-MS), which is capable of detecting VOCs down to parts per trillion.
Using the breath-test method, the team found a significant difference between the breath profiles of the mice infected with the bacteria and a group of uninfected mice. The team was also able to distinguish the two bacteria with a statistically significant level, and also able to distinguish between two strains of P. aeruginosa that were used.
"We have strong evidence that we can distinguish between bacterial infections of the lung in mice very effectively using the breathprint SESI-MS approach and I suspect that we will also be able to distinguish between bacterial, viral and fungal infections of the lung,” Hill noted.
"To that end, we are now collaborating with colleagues to sample patients in order to demonstrate the strengths, as well as limitations, of breath analysis more comprehensively," Hill concluded.