The 15-year-old from West Melton suffers from the kidney disease, nephrotic syndrome, and underwent her second kidney transplant in January last year.
She was in Starship Hospital for a week in October after her kidney showed signs of rejection.
Her mother Sarah Manson-Collins said she has lost a lot of function in the organ recently.
“The last bit of rejection really affected the function to the point where they have actually been investigating her veins for a fistula so she can start dialysis at some stage," she said.
“We’re not at that stage just yet but we know it will be inevitable, it’s coming."
Mrs Manson-Collins said Maddie will continue to have blood tests to monitor her kidney function.
“We want to get through this Christmas period and at the moment it’s just about maximising all of her different medication levels to get her feeling the best she can.
“Which is difficult considering she is basically heading towards full renal failure again.”
She said they can see the difference the declining kidney function is having on Maddie.
“There’s certain things we can just tell like food is tasting different, she’s lethargic, her memory isn’t as great as it was, little things like that.”
Mrs Manson-Collins said they don’t have any concrete plans for what will happen next if the kidney fails.
“Maddie’s name is down on some overseas lists for a bionic kidney when the trials start-up. It is probably still a few years away but it’s something.
“There is huge research going into Maddie’s disease all the time. There are lots of really cool things coming out and we’re kind of just saying hang on a bit longer Maddie.”
In spite of everything, having the ability to spread the word about organ donation has been great, she said.
“We want to show the difference organ donation can make to people’s lives.
"Yes, Maddie has had it rough, but this kidney has given her a couple of years without being on dialysis and that’s much better than being on it.”
Maddie received a ‘miracle’ second kidney transplant in January last year after being told there was only a two per cent chance of finding a match in New Zealand.
The first was donated six years ago by her father Adam but her body rejected it.
