Imagine if dogs could do what they do best — sniffing urine — to help humans.

That’s just what Assistance Dogs of Hawaii, a nonprofit group that trains canines to assist people with physical disabilities, is hoping to accomplish with its latest research project.

Past studies have examined how dogs use their keen sense of smell to detect medical conditions such as low blood sugar levels in diabetes patients and the presence of cancer cells. Assistance Dogs of Hawaii is exploring how the animals can help detect urinary tract infections early in humans to prevent hospitalization.

Five dogs — Astro, Abe, Sadie, Sam and Scout — participated in the study’s first phase, which involved detecting E. coli, the bacteria that causes the majority of urinary tract infections, in urine samples at the nonprofit’s main Maui campus starting in May.

The dogs were presented with five boxes containing vials of urine samples and were trained using positive reinforcement (a click and reward) to sit in front of the one containing E. coli while ignoring the healthy specimens.

They just completed more than 2,000 trials with a 99 percent accuracy rate and full results will soon be published in a medical journal, according to Mo Maurer, executive director of Assistance Dogs of Hawaii.

"The results are very promising," said Maurer. "The exciting thing about this research is it has the potential for immediate application."

The dogs can be particularly helpful to people with spinal cord injuries who do not feel the warning signs of a urinary tract infection but are particularly susceptible to them due to spinal cord damage and use of catheters.

Urinary tract infections are also the most common hospital-acquired infection.

"Usually, a bladder infection has symptoms like urinary frequency and urgency, sometimes pain," said Angel Willey, an obstetrician and gynecologist at Kapiolani Medical Center for Women and Children. "A paraplegic or quadriplegic doesn’t have those sensations and by the time they start to get sick, it’s past that symptom stage, which can lead to kidney infection or sepsis."

If dogs can help detect an infection before getting to that point, patients could be treated with antibiotics, saving them from hospitalization, she said.

The five dogs range in age from 1 to 8 years old and were selected from dozens of candidates. Many are already service dogs, including Sam, who works as a therapy dog, and Scout, who is a "wounded warrior" dog working with war veterans.

Each has their own personality and working style, Maurer said, but more important is the accuracy and speed in which they detect the target odors.

In the second phase of the study that will start in September, Maurer will train working service dogs to detect urinary tract infections in their disabled human partners over a two-year period.

Astro and Abe, both young Labrador retrievers that completed the first phase of the study, will be paired with disabled patients. The patients will present urine samples to the dogs on a regular basis with a command like "check" to test their scent abilities. Dogs that work at major hospitals in Hawaii would begin training.

In the first phase of the study, Maurer found that the dogs could detect E. coli even in samples diluted to one-tenth of 1 percent. The biggest challenge, she said, was getting the dogs to ignore the plethora of other scents in the urine sample.

Maurer is excited about teaching the new skill to all of her service dogs and is sharing what she knows with dog trainers in Japan, Korea, Argentina and elsewhere.

The Makana Aloha Foundation provided initial funding for the project and is offering a match of up to $50,000 for the next phase of research.

"With their incredible olfactory capabilities, dogs already know if we have cancer, infections or other illness, but they don’t know how to tell us," said Maurer. "We are teaching them to communicate what they already know."