Electronic 'Nose' Sniffs Out Pneumonia, Sinusitis
Device already used in food industry has potential for medicine
FRIDAY, April 30, 2004 (HealthDayNews) -- An electronic "nose" device about the size of your TV remote control can sniff out pneumonia and sinus infections by analyzing a patient's breath, researchers report.
Dubbed the Cyranose 320, or the "e-nose," they hope the device will be especially useful for providing a faster, easier and cheaper way to detect pneumonia -- especially in hospitalized patients -- and sinus problems.
"About a quarter of patients who are on a ventilator [for breathing help] for more than two days get pneumonia," said Dr. Neil G. Hockstein, a clinical instructor of otorhinolaryngology at the University of Pennsylvania School of Medicine and one of three Penn researchers who will present three studies on the device April 30 at the annual meetings of the Triologic Society and The American Broncho-Esophagological Association in Phoenix.
While there are a number of ways to detect pneumonia, he said, none are foolproof. And primary-care physicians, often challenged to decide whether a patient has sinusitis, an infection of the sinuses, could benefit from the device too, he added.
"I say the device looks like a transistor radio, a Walkman or a TV remote, depending on how old you are," said Dr. Erica R. Thaler, an associate professor of otorhinolaryngology at Penn who is a co-presenter at the meeting. "It's so lightweight you can hold it in one hand. It's attached to a laptop computer, which is doing the data analysis."
The patient exhales normally while wearing a standard oxygen mask. The sensors within the device respond to particular molecules in the patient's expired breath.
"Individual bacterial colonies each have a characteristic odor," said Dr. William Hanson, a professor of anesthesiology at Penn and senior author of the studies.
Sampling takes about 10 or 15 minutes, Thaler said. After analysis, the result is a "smellprint" that can tell a doctor whether or not bacteria are present, and which types. By evaluating the odors, doctors can make a diagnosis of pneumonia and sinusitis and decide if a patient, for instance, actually has sinusitis or just a cold.
The device, which costs about $8,000, is already used in the food and beverage industry, to test for food spoilage and for quality control, the researchers said. It has not yet been approved by the U.S. Food and Drug Administration for medical uses.
In one study of 25 patients with suspected pneumonia, the researchers found the e-nose diagnosed 92 percent of the true pneumonia cases among 25 patients, as confirmed by CT scans of the lungs. In a second study, the device was found to be 70 percent effective in pneumonia diagnosis.
In the sinusitis study, the device was effective at detecting 82 percent of the cases among 22 patients. About half were diagnosed with sinusitis.
The University of Pennsylania funded the studies, with a partial additional funding by the manufacturer of the device.
One expert says the device might prove useful if it is sensitive enough. "The device would have to be sensitive and specific enough to be able to distinguish benign colonization [of bacteria] from pneumonia that needs to be treated," said Dr. Theodore Wynnychenko, an assistant professor of anesthesiology at Northwestern University's Feinberg School of Medicine.
To learn more about sinusitis, visit the National Institute of Allergy and Infectious Diseases. To learn more about pneumonia, visit the American Lung Association.