Marcella Creedon says the system detects infections before she is ill
Cystic fibrosis patients are being helped to avoid hospital treatment by using a mobile phone to monitor their condition.
Marcella Creedon, aged 20, is one of those testing the daily checking system.
Marcella, who is studying to become a veterinary nurse at Bristol University, has been using the O2/e-San system CF for eight months.
"The system gives me a massive amount of reassurance," she said.
"It's great to know that the people who are looking after me can monitor my condition every day."
Marcella started to notice the effects of CF when she was 12.
"While I was at secondary school, I found it difficult to keep up with people. I had lots of chest infections and I had to take time off.
"It was particularly bad in the last two years of school. I didn't realise it at the time, but I also needed a liver transplant."
Despite her illnesses, which needed regular hospital treatment, Marcella was able to gain a place at Bristol.
It was here that she received the liver transplant she needed.
She also began trialling the mobile phone technology, which comes attached to a lung function monitor.
Each night, Marcella blows into the machine. The readings are then sent to a hospital computer via the mobile phone.
She also sends in information about how she is feeling.
Doctors treating CF patients want to pick up "exacerbations", where infections lead to a worsening of lung function.
These are often not picked up until they are at an advanced stage and patients need to be given intravenous antibiotics.
But this study, carried out by doctors at Bristol Royal Infirmary, is aimed at picking up signs of infection early, allowing patients to be given oral antibiotics they can take at home.
If data shows two or three symptoms have worsened over three days, patients are classed as having an exacerbation.
They are then invited in to see a doctor and treated with a course of oral antibiotics.
Marcella says the system has already predicted the onset of two potentially serious lung infections.
"One night, after I'd used the system to send data about my symptoms to the team looking after me, they rang to tell me I was heading for an infection.
"I felt fine and didn't believe I was going to become ill."
Marcella didn't go to the hospital. But the next day she did become ill with a chest infection.
"The second time they rang to tell me the signs showed I was developing an infection, I went."
Lung function decline
So far, 30 patients are taking part in a trial of the system. Researchers hope a total of 50 will take part.
Dr Nabil Jarad, the consultant respiratory physician, said: "In general, the more severe the exacerbation, and the more frequent, the more rapid the decline of lung function, and the shorter the life expectancy will be.
"We don't know yet whether early intervention with oral antibiotics will delay mortality.
"But that would make intuitive sense."
The system costs up to £400 per patient, compared to up to £2,000 for a course of IV antibiotics.
Rosie Barnes, chief executive of the Cystic Fibrosis Trust, said: "We are constantly looking to improve treatments and care for the thousands of people living with CF.
"This is an exciting use of emerging technologies and providing real time data can only help the CF teams keep patients as healthy as possible.
"We look forward with great interest to seeing the results of the research study."