In an ideal world, a medical mystery could be solved with a device that quickly and cheaply takes a noninvasive sample and reports back with whatever condition a patient is suffering from – a real life “Star Trek” medical tricorder of sorts.
Perhaps more importantly, diseases could potentially be noticed by such a machine before their full-blown symptoms have spread throughout the body.
That science-fiction idea moves a whole lot closer to reality with the recent development of a disease-detecting breathalyzer, described in a study published December 21 in the journal ACS Nano.
By analyzing a breath sample, the device can identify 17 different diseases, including two types of Parkinson’s disease, Crohn’s, multiple sclerosis, kidney disease, and cancers including lung cancer, colorectal cancer, prostate cancer, and ovarian cancer.
"One of the major challenges in the modern era of disease diagnosis is how we can detect the disease when we are still feeling healthy," Hossam Haick of the Technion-Israel Institute of Technology, who led the 56-researcher team that developed the breathalyzer, says in a video describing the work. Haick says the device, which they call the "Na-Nose," is capable of catching a disease in the early stages and may even be able to predict people that are at high risk for certain conditions.
The 86% accuracy rate reported in the study, which tested 1404 sick and healthy patients in 9 locations around the world, is not yet good enough to be used clinically as a diagnostic tool. But this shows very clearly one potential future for early and easy disease diagnosis.
A breath of diseased air
With every breath, our lungs expel carbon dioxide from our bodies, ready to be replaced with fresh air. There are also other components of air, nitrogen and unused oxygen. But there's also much more.
The researchers identified more than 100 other chemical compounds exhaled in each breath, 13 of which were associated with certain diseases. The device includes an "artificially intelligent" nanoarray which analyzes the chemicals to assess what levels seem healthy, not just relying on one simple definition of levels that are "too high" or "too low." When concentrations of these chemicals differ from what's expected to be "normal," it's an indication that something is off.
As a press release announcing the study points out, this is far from a new idea - in 400 B.C., Hippocrates told students "smell your patients' breath," since a sweet smell would indicate diabetes, for example.
Modern efforts to improve this technology have involved training animals like dogs to sniff out cancers and other illnesses. But a device that can accomplish the same would make it easy to use this tool around the globe, without the need to carefully train animals.
In the video, Haick says they're working on ways to incorporate this sort of technology into smartphones, so a simple conversation might reveal the early stages of illness. And while that might seem a bit terrifying, the early detection of disease is essential. For an illness like lung cancer, it can increase survival rates from around 10% to something like 70%.
Again, before such a device could enter wide use, researchers will need to improve accuracy levels. The study reports that new generations using better materials might be more accurate. They'll also need to determine how well the device can analyze the effects of multiple diseases that may exist simultaneously.
Still, as potential future tool, this shows promise.
"Diagnosing cancer currently is a very painful process," says Nisreen Shehada, also of Technion, in the video. "If we can add a step that is not painful, that is not invasive, something that people won't be afraid of, I'm hoping that more people [will] be tested and that way we can diagnose cancer at much earlier stages."