health & science

New tech takes the guesswork out of gut diagnosis

New technology developed by scientists at the University of Auckland could soon enable faster diagnosis of gut conditions often difficult to detect.

Instead of requesting patients cut out certain foods, or relying on chemical tests or even a physical probe to examine the digestive tract, Dr Peng Du and his 12-strong research team at the university’s bioengineering institute are using electrode technology to map what is wrong in an unhealthy gut through bioelectrical activity.

Dr Du, who has developed the technology through the university's spin-out company FlexiMap, said eight polymer patches embedded with electrodes and a copper circuit are placed on the internal stomach surface to measure the bioelectrical activity of the gut.

As a person digests food, it is regulated by bioelectrical activity. Discrepancies in the activity - which are picked up by the FlexiMap technology - indicate a problem in the digestive process.

“Basically, it’s the difference between somebody who keeps making diagnosis or treatment based on symptoms, or somebody who makes these diagnoses based on quantifiable figures,” Du said of the bioelectrical mapping technology.

“At the moment, if you have gut pains and you go to the doctor, they might suggest you change your diet and return in a week’s time. If you go back in a week, and nothing has changed then you might have to do another test, which could take another few weeks.

“It’s a process of elimination with these current tests….whereas bioelectrical mapping can tell you a lot about how your body or how your gut functions.”

So far, the technology - which contains 32 recording channels that transmit readings of gastrointestinal biochemical activity to a computer, similar to how an electro-cardiogram measures heart function - has undergone one clinical trial.

The control group of healthy patients were tested in New Zealand, while sick patients underwent tests in the United States.

Because the current form of the electrode has to be applied directly to the surface of the stomach, to qualify for the clinical study participants had to already be undergoing a surgical procedure.

Bioelectrical results from the control group were compared to the participants with known diseases so researchers could begin to map out what different illnesses looked like. Currently, the electrodes are being used to detect two conditions: chronic unexplained nausea and vomiting, and gastroparesis. Gastroparesis occurs when the pacemaker cells in the stomach stop working, preventing proper digestion. It can cause severe malnutrition

“We [would] take the recording for about 10 to 15 minutes, then we would let the surgeons carry on with their surgical techniques,” Dr Du said.

Next, the research team is focusing on enhancing the electrode technology so the patches, and mapping, work when placed on the patient’s skin.

“At the moment, we take a recording directly from the stomach which gives the best signal. We are trying to develop the next generation of electrodes so that we only need to put them on the surface of a patient’s body so it can [eventually] be something you sit down in the doctor’s room and do.”

Further research could also examine the efficacy of different treatments for gut conditions, Dr Du said.

“A lot of the efficacy or tracking of the outcome of current treatments is based on quite a subjective survey.They basically go back to the patient and say how do you feel.

“That’s really important, but it’s quite inconsistent, whereas this electrical recording is something that we would be able to get from every patient and that would basically form a more structured way to monitor progress of treatment,” he said.