Substance Detection Golden Retrievers: Illness and Disease

Dogs are used to warn of epileptic seizures, low blood sugar, high blood pressure, migraine headaches, and heart attacks. Research in this area is based on the theory that disease causes subtle chemical changes in the body or alterations in metabolism, which in turn releases a different smell, or chemical marker.

“This isn’t anything magic,” says Dr. Larry Myers, associate professor at the Auburn University College of Veterinary Medicine in Auburn, Ala., who has personally tested the olfactory capabilities of more than 4,000 dogs over the last two decades. “Physicians have always used their own senses to determine the presence or absence of disease.” In fact, diabetes was once diagnosed by smelling or tasting a patient’s urine. Some types of infections present in burn victims can also be detected by the smell of a patient’s skin, and we all know that bad breath can often be a sign of periodontal disease.

  Epilepsy: Seizure Alert Dogs

Dogs sense seizures, Health24, November 11, 2005

"It's [epilepsy] a chronic condition and [an attack] is literally an electric storm in the brain that can change behaviours," explained Dr Blanca Vasquez, director of clinical research at New York University's Comprehensive Epilepsy Centre. While seizures can vary greatly in their intensity and outward manifestations, many are preceded by sensations known as an aura, she said.

Not known what dogs are responding to
Even from far across a room, seizure-alert dogs seem to be able to pick up on extremely subtle physiological changes - minute alterations in odour or movement - that may begin anywhere from 45 to five or 10 minutes before an actual attack. "More research needs to be done," Arnold said. "We don't exactly know right now what the dogs are responding to."

But their ability to sense these changes for their owners can be invaluable, since early warning of a seizure's onset helps people with epilepsy find a safe environment or take precautionary measures. The Labradors and retrievers trained by the experts at Alpharetta, Ga.-based Canine Assistants begin their 18 months of instruction at just 2 days of age, learning over 90 standard commands. More mysteriously, some protective measures seem to come to the dogs by instinct, Arnold said. For example, when sensing an oncoming seizure, "they tend to want their person to lie on the ground," she said.

As any person with epilepsy will tell you, that's about the most sensible action an individual can take before a seizure, since falling is the leading cause of serious injury during an attack.

Seems to know instinctively
"It's fascinating - dogs who have never seen anyone have a seizure will tug at their person's sleeve, they want you on the ground," Arnold said. "How do they have that instinct that lying on the ground is safer? We have no idea."



The Epilepsy Foundation notes that interest in seizure dogs began in the mid-1980's, when a woman with epilepsy who was taking part in a Washington state prison project involving dogs discovered that one of the dogs seemed to know when she was going to have a seizure. The Lifetime TV drama, "Within These Walls," is based in part on this experience. Now the term is used to cover activities such as: dogs trained to bark or otherwise alert families when a child has a seizure while playing outside or in another room or to lie next to a person having a seizure to prevent injury.

Although these dogs are responding no differently than other assistance dogs, the issue of seizure prediction is a cloudy one as most report that dogs with this ability have only developed it over time, the talent actually discovered accidentally. In 1998, Roger Reep, Ph.D., an associate professor in the department of physiological sciences at the University of Florida, surveyed 77 people between the ages of 30 and 60 who had epilepsy. The survey asked about their quality of life, medical status, attitudes toward pets, ownership of dogs, and their pets' behavior prior to and during a seizure. Only 3 out of the 31 felt that their dogs seemed to know when they were going to have a seizure (10 percent). Another 28 percent said their dogs stayed with them when they had a seizure. According to his research, the behavior seems to occur spontaneously and may occur in as many as one in ten situations when the owner is having at least one seizure per month. Dr. Reep concluded that reports of seizure-alerting behavior in dogs should be viewed as credible, but with caution.

Dr. Stephen W. Brown, a British neuropsychiatrist and epilepsy specialist, and Val Strong, a behavioral scientist and animal trainer, reported in 1999 in the European Journal of Epilepsy Seizure that, working with people with epilepsy and dogs together, they were able to train some of the dogs to warn of seizures. The training was based on reward-based operant conditioning. In effect, the dogs got a reward every time their owners had seizures. "After a while those dogs that are going to be able to act as seizure-assistance dogs start to alert and expect their reward before the person's had the seizure," Dr. Brown said. The dogs he was training were sometimes able to give warning as much as 15 to 45 minutes before the actual seizure occurred. The way the dogs behaved took different forms, from pawing in a special way to simply approaching the person and barking. Dr. Brown also found that, following this type of training, the actual number of seizures decreased.

In the Seizure March 2003 article, Seizure-alert dogs: a review and preliminary study (Dalziel; Uthman; Mcgorray; and, Reep, Department of Neuroscience, College of Medicine, University of Florida), the findings suggested that some dogs do have the innate ability to alert and/or respond to seizures. The research additionally suggested a trend in the type of seizure/auras dog may be alerting to. However, the success of these dogs depended primarily on the handler's awareness and response to the dog's alerting behavior. The authors did see the need for further research to aid in the selection of those who may benefit from seizure-assist dogs, for identification and further training of these dogs and possibly the development of seizure-alerting devices.

A more current review of the literature can be seen in Drs. Doherty and Haltiner's 2007 Neurology article, Wag the dog: Skepticism on seizure alert canines. Reports of dogs that can predict their owners' epilepsy seizures have been anecdotal and not objectively confirmed by doctors and researchers. The article also looks at the controversy regarding Psychogenic NonEpileptic Seizures (PNES), with dogs thought to be responding more to psychological seizures, rather than epilepsy seizures. PNES may look like epileptic seizures, but are not caused by abnormal brain electrical discharges. Instead, they are a manifestation of psychological distress. By definition, PNES are a physical manifestation of a psychological disturbance and are a type of Somatoform Disorder called a conversion disorder.

Dr. Michael J. Doherty, MD, of the Swedish Epilepsy Center, and a member of the American Academy of Neurology, said the findings raise several questions that need to be further investigated. "If dogs can predict psychological seizures, could the seizures be a conditioned response to stereotypical dog behaviors? Does having a seizure alert dog lead people to have psychological seizures more or less often? Given the cost of training seizure alert dogs, should people requesting one be screened for psychological seizures?"

Pseudoseizure Dogs, a 2007 article In the American Academy of Neurology from Dr. Gregory L. Krauss, MD, of Johns Hopkins University School of Medicine, concludes that those with psychogenic seizures need psychiatric evaluation and appropriate treatment, not a specially trained dog for epileptic seizures. "This is important because the treatment is very different for a person with epilepsy and one with psychological seizures, which stem from emotional difficulties," said Krauss. "Epilepsy drugs are not effective for psychological seizures, and they often have side effects. And with proper treatment and counseling, psychological seizures can often be eliminated."

Krauss said it's possible that people with psychological seizures may seek out service animals for support. He noted that some people with epileptic seizures may benefit from seizure response dogs. "Seizure response dogs can help people during seizures and stay by them when they are unconscious and provide companionship that aids them in dealing with a chronic disorder," Krauss said. "People with nonepileptic seizures require psychiatric evaluation and behavior therapy. This study demonstrates the importance of establishing an accurate diagnosis of epilepsy before obtaining a seizure response dog."


Diabetes: Medical Alert Dogs
Dogs for Diabetics is an innovative non-profit organization that provides quality medical alert assistance dogs to youth and adults who are insulin-dependent type 1 diabetics through a program of training, placement, and follow-up services. Dogs4Diabetics dogs have been specifically trained to identify, and more importantly, act upon the subtle scent changes that hypoglycemia (low blood glucose) creates in body chemistry, changes undetectable to their human companions.

Low blood sugar initially causes stomach cramps, disorientation and a sweat, but later the body becomes accustomed to these lows and stops sending out danger signals. That's where these specialized dogs come in, earning the right to sleep in the room with its owner. While everyone is certainly different, they say 3 a.m. seems to be the favored time for a crash. In a November 5, 2006 San Francisco Gate article, written by Sam Whiting, we learn about such times and how these canines step up to the plate.

"My blood sugar suddenly goes low and I don't wake up. I don't feel anything and suddenly there will be a 130-pound golden retriever jumping on me," says Devin Grayson, who is 36, lives in Oakland and has been Type 1 for half her life. Once rousted she checks her blood sugar to make sure Cody is right. A diabetes dog does not get its owner out of a finger prick to draw blood and test. Grayson goes low at night three times a week, and Cody hasn't been wrong in six months. He's a more accurate predictor than the meter, because his nose picks up a trend downward in blood sugar that the meter won't. If Grayson were to become non-responsive, Cody has been taught to find help and lead it back, which Grayson describes as a "Timmy's-in-the-well episode.''

All the Lassies lodge with foster families while they are being trained. The curriculum is a simple reward system. The hypoglycemic scent is captured on the shirt of a hypoglycemic diabetic and hidden among trainers. Detect the smell on the right person and the dog gets a reward. The humans take more training than the dogs. "We start with Puppy 101," Ruefenacht says. Applicants must have control over their diabetes and fill out a questionnaire available at the Web site They are looking for a perfect match between woman and best friend,

Cody continues sharpening his skills while Devin works as the Director of Communications for Dogs4Diabetics.

At Heaven Scent Paws, their trained Diabetic Alert Dogs detect and alert their diabetic partner and support team (parents, spouse, friend, etc) to both low blood sugar (hypoglycemia) & high blood sugar (hyperglycemia).



Cancer Detection Dogs
Canine cancer detection is an approach to cancer screening that relies upon the olfactory ability of dogs to detect very low concentrations of the alkanes and aromatic compounds generated by tumors. Although the first suggestion of this approach in a medical journal dates back to 1989, there was little further investigation for the next decade. However, two studies (one published in 2004 and one in 2006) had promising results, with the 2006 report claiming a 99 percent accuracy in detecting lung cancer, although both studies were preliminary and involved small numbers of patients.

In 1994, Dr. Armand Cognetta, a Tallahassee dermatologist and retired Tallahassee police officer Duane Pickel, got together to see if dogs could be trained to detect cancer. As we have several successful Goldens in arson and drug detection, it seemed possible to train for cancer detection. To a dog's powerful nose, it appears that cancer cells have an odor that is different from that of healthy cells. Golden Retriever owner and trainer Glenda Manucy and her dog, Colabaugh's Morninglo Breeze UDX, MH, joined the team in June 1994. It only took Breeze a month to be able to do test searches. Here she is sniffing at every Band-Aid, searching for the one with cancer cells. Breeze correctly identified the one with the cancer cells and then alerted this by sitting. If asked to "Show me," she would tap the Band-Aid with her paw.

A lung specialist, Fr Clinton "Bud" Bailey joined the project, interested in learning whether a similar procedure could be used for the early detection of lung cancer. In December 1994, a specially made rack containing sample test tubes was provided to teach Breeze to detect lung cancer cells. Using this rack, a patient would breathe into one of the tubes, which was then sealed, and racked with the others. As she walked along one side of the rack, the tubes were opened. That allowed Breeze to smell the air coming from the tube. Just like the skin cancer tests, the signal of alerting to a different smell was to sit in front of the suspect tube.

More controlled research needs to be done, and the next step may also be to try and determine just what it is that these dogs are calling cancer. Pickel and Manucy would like to continue to be involved in any new research. They would also like to be able to train Physician Assisting Canines (PACS) for other doctors to continue this work on skin and lung cancer detection. This kind of detection, of course, would not replace the diagnosis needing to be done by a physician. Yet, this method may be able to get people to their doctor before they have outward symptoms. And, then lives could be saved.

More recent small-scale studies of dogs’ ability to detect the chemical markers of cancer, specifically melanoma, have shown very promising results with a dog's ability to differentiate between healthy skin cells and cancerous ones. Work is under way to determine whether dogs can accurately diagnose prostate cancer.

Biodiagnostics is the diagnosis of human diseases with the help of animals such as sniffer dogs. Understanding how dogs detect cancer by smell may soon help scientists develop new technology to help detect melanoma and other cancers at early stages. Though scientists do not know yet whether dogs detect enzymes, proteins, antibodies, or other molecules of melanomas, further research with canines may allow them to develop new medical equipment.

There are two proposed benefits, assuming that further studies corroborate the initial results. Some researchers believe that dogs will become integrated directly into patient care, akin to their use in detecting bombs, drugs, and missing people. Others recommend that the skill of dogs in detecting cancer would be more appropriately confined to labs, where gas chromatographs could be used to isolate which specific compounds the dogs identified.



Print and Video Web Resources

    Cancer Detection Articles    Medical Illness Detection Articles
       Diagnostic Accuracy of Canine Scent Detection in Early /
         Late-Stage Lung & Breast Cancers
       Canines Detect Odors in Cancerous Tissues
         (U of SC Brodie Lab)
       Olfactory Detection of Human Bladder Cancer by Dogs:
         Proof of Principle Study
       Dogs Excel In Cancer-Sniff Study:
         Identify Lung, Breast Cancer Sufferers By Smelling Breathth
       Dogs Smell Cancer in Patients' Breath, Study Shows
       Moist Nose Shows Promise in Tracking Down Cancers
       Dogs Trained to Sniff out Bladder Cancer
       Cancer Detection Goes to the Dogs
       Dogs Trained to Sniff out Bladder Cancer
       Can Dogs Sniff Out Cancer?
       Doggie Noses: Cancer Detectors?
       A Case of Breast Cancer Detected by a Pet Dog
       Seizure Assistance Dogs
       Trainer Teaches Dogs to Warn Before Seizures
       Can Dogs Sense When You're About to Have a Seizure?
       Dogs Foretell Imminent Illness Episodes in Humans
       Seizure Alert Dogs are Focus of UF Study
       Seizure Dogs: Helping Paws (with Golden Chelsea)
       Medical Detective Dogs
       The doggie will see you now
       Sensing Sickness
   Illness and Disease Video Clips
    Dogs Sniff Human Illness
    The Odor Of Cancer
    Dogs May Sniff Out Cancer
    Sniffing For Disease?
    Wrigley Detected Brain Tumor
    Can Dogs Sniff Out Seizures?


TaleTell: Your own Stories of Disease Detection Goldens
Meet some wonderful 4-footed detectors. And, if you have a story to tell of a Golden alerting to: an approaching seizure, low blood sugar, migraine headache, rise in blood pressure, presence of cancer, etc., just send it along with photos to: