Sniffing Out Disease With eNose

Electronic Nose Helps Detect Cancer And Other Illnesses

By John Schieszer

MSNBC Contributor

SEATTLE -- Seattle resident Salvatore Cagnina is hoping that a new nose will help him with his sinus problems. Cagnina is not banking his hopes on an organ transplant, but on an electronic nose, or eNose, that can sniff out infections and even tell a physician what type of therapy to prescribe.

Cagnina, A 45-year-old paint salesman, has been plagued with sinus infections for years.

"I had so many problems. I was tired all of the time. I couldn't concentrate," says Cagnina.

Sinusitis is the most common chronic condition in the United States, surpassing even high blood pressure, according to the Centers for Disease Control and Prevention. Patients are rarely cured by antibiotics and only about half benefit from surgery, experts say.

Now, researchers at the University of Pennsylvania Medical Center in Philadelphia think they may have discovered a faster, cheaper way to diagnose and treat sinusitis as well as a range of other illnesses using a device called the Cyranose 320 or electronic nose. Manufactured by Cyrano Sciences Inc. of Pasadena, Calif., the machine incorporates biosensor technology, which has been used for decades in the perfume, wine and food industries and is now making its way into the medical field.

The eNose is able to produce a smellprint of a patient's breath sample that can help doctor's determine whether bacteria are present, and if so, what kind. By identifying the pathogen involved in an illness, the eNose can also point physicians toward the most effective antibiotic for treating a patient's problem.

"I think there is very good likelihood that ultimately it would be used in your doctor's office," says Dr. C. William Hanson III, associate professor of anesthesia and an expert in critical care medicine at the University of Pennsylvania.

Hanson says the Cyranose 320 did well at identifying bacteria in a study involving 50 sinusitis patients and more than 100 mechanically ventilated, critical care patients, who are prone to developing bacterial infections.

A Nose Unlike Any Other

Despite its name, the eNose doesn't look anything like a nose; it looks more like a walkie-talkie. The device, which costs around $8,000, contains an array of sensors consisting of carbon-black/polymer composites. The patient's exhaled breath passes over these sensors, which then expand like a sponge, changing the resistance of the composites. The change in resistance produces unique patterns that are displayed in maps or dot patterns on a computer screen. Each type of bacteria appears as its own pattern.

Hanson says the eNose technology could one day be incorporated into a ventilator and used to continuously track a hospitalized patient's progress by sniffing out any infections that may develop.

Or, as in the case of sinusitis sufferers, the device could simply be used by a physician to make a rapid diagnosis and develop an appropriate treatment plan.

Reducing Antibiotic Use

Dr. Erica Thaler, associate professor of otolaryngology at the University of Pennsylvania, says sinusitis is very difficult to diagnose and treat because it is a moving target. Sometimes the condition is triggered by a virus, but then develops into a bacterial infection.Since antibiotics are only effective against bacterial infections and are completely useless against viral infections, the eNose can help prevent the unnecessary use of antibiotics.

"We are living in a world where antibiotics are greatly over prescribed and we are now in a situation where it matters a lot if we are right or not because of the drug resistance and because of antibiotic overuse. You don't want to use these drugs unless it is absolutely necessary," says Thaler.

The eNose may be particularly useful in diagnosing otitis media, or middle ear infections, in children. More children are treated for ear infections than any other childhood health problem, but it is estimated that only one in eight children with ear infections actually benefit from antibiotics, a recent study found.

"A lot of people want antibiotics and we spend a lot of time explaining why they should not take antibiotics," says Dr. Ken Haller, assistant professor of pediatrics at St. Louis University School of Medicine. "So, if you can actually show the parent with the eNose that antibiotics are not going to work, then that would make a big difference."

The Scent Of Lung Cancer

At the Cleveland Clinic Foundation in Cleveland, Ohio, researchers have begun testing the eNose in a study on lung cancer patients and have found that the exhaled breath of lung cancer patients has distinct characteristics that can be identified with the device.

The researchers presented their findings in May at the annual meeting of the American Thoracic Society held in Seattle. They reported that the device could be useful in lung cancer screening and diagnosis, as well as for monitoring the recurrence of disease in patients after they receive treatment.

Dr. Serpil Erzurum, an eNose researcher at the Cleveland Clinic, says her colleagues are pleased with their findings and are optimistic that the eNose may become a new weapon in the war against lung cancer, the number-one cancer killer in the United States.

"It might be a way of early detection," says Erzurum. "Early detection is the goal for any cancer. With lung cancer, it is frequently silent until it is metastasized (spread throughout the body) or large."

Dr. Steve Sperling, a radiologist at Overlake Hospital in Bellevue, Wash., says the eNose could be particularly helpful when combined with X-rays and other screening devices.

"Often lung cancer can be obscured on plain chest radiographs, especially early in the disease," says Sperling.

Other Applications

The developers of eNose technology believe it will soon have a wide range of applications. Cyrano Sciences is already working with the Department of Defense and the Department of Homeland Security to develop chemical and biological sensors.

Hanson believes the devices will one day become quite commonplace and will be used to diagnose everything from kidney disease and cirrhosis of the liver to skin cancer.

"The beauty of these things is that they can be miniaturized, inexpensive, non-invasive and potentially something that can be used in doctors' offices or even at home," he says.

A British company, Osmetech Plc., is also working on developing biosensor technology and recently received approval from the U.S. Food and Drug Administration to market its version of the eNose for diagnosing bacterial vaginosis.

In addition, Osmetech sold $700,000 worth of the biosensor technology to China, which plans to use it to help control the spread of SARS.

"You could use this nose in an airport to screen passengers. You could use a breath analysis to see if someone has an inflammatory lung disease such as SARS," says Hanson.

As Hanson points out, dogs, cats and other animals depend on their noses for survival. Now, humans are simply following their lead.

This article posted June 21, 2003.