Just as the human nose interprets a whiff of smoke as a warning of fire, electronic noses can detect the unique "scent signatures" of diseases, from bacterial infections to lung cancer.
Consisting of arrays of chemical sensors, these high-tech noses distinguish the breath, urine and blood of the sick from those of the healthy. Most devices are still in the experimental stages, with some being tested on patients with suspected pneumonia and other lung diseases, sinus infections, diabetes and cancer. The technology could screen and diagnose diseases and monitor any recurrence right in the doctor's office or at the patient's bedside.
For The Record
Los Angeles Times Wednesday May 21, 2003 Home Edition Main News Part A Page 2 National Desk 1 inches; 46 words Type of Material: Correction
Electronic noses -- An article about electronic noses in Monday's Health section incorrectly identified the musky breath odor that Roman doctors called fetor hepaticus as the scent of kidney failure. Fetor hepaticus is the scent of liver failure. Kidney failure has a unique scent as well.
For The Record
Los Angeles Times Monday May 26, 2003 Home Edition Health Part F Page 8 Features Desk 1 inches; 50 words Type of Material: Correction
Artificial noses -- In a story about electronic noses that ran in Monday's Health section, the musky breath odor that Roman doctors called fetor hepaticus was incorrectly identified as the scent of kidney failure. Fetor hepaticus is the scent of liver failure. Kidney failure has a unique scent as well.
"What you're seeing is the emergence of the technology to be a diagnostic tool," said Steve Sunshine, chief executive of Cyrano Sciences in Pasadena, which makes an electronic nose undergoing tests at several medical centers.
The practice of diagnosing illness through breath smells dates at least to Roman times, when doctors called the musky breath of kidney failure patients fetor hepaticus. Doctors today liken the distinctive breath of diabetics with dangerously high blood sugar to the scent of a popular brand of chewing gum.
In the last few decades, scientists worldwide have been developing ways to detect the chemical signatures of food spoilage, pollution and biological attacks, and several teams have been zeroing in on medical applications. Because diseases create distinct changes in the gases we exhale and in the gases emitted by bacteria infecting our blood and urine, electronic noses can be programmed to sense their chemical signatures.
So far, only one electronic nose has been approved in this country for commercial use. In November 2001, the U.S. Food and Drug Administration said Osmetech of Crewe, England, could market the Osmetech Microbial Analyser for detecting the urinary tract infections that plague millions of Americans each year. The device, based on technology developed at the University of Manchester, analyzes gases from bacteria in urine within hours; bacterial cultures take days.
In January of this year, Osmetech announced that the device had also been approved for diagnosis of bacterial vaginosis. Using vaginal fluids, it distinguishes bacterial vaginosis, an infection linked to miscarriage and premature delivery, from other common vaginal infections.
