Kidney transplant: Three-year-old is smallest patient - BBC News
Olly Cartmill was 13kg when he had the life-saving operation, getting a kidney from his grandmother.
Olly's one-year-old sister Etta will also need a kidney transplant when she is a little older

A three-year-old boy has become the smallest - and one of the youngest - recipients of a kidney transplant in Northern Ireland.

Olly Cartmill was just 13kg (29lbs) when he underwent the life-saving operation, receiving a live donation from his grandmother Michelle.

Olly was born with an extremely rare condition known as TTC21B.

His one-year-old sister Etta has the same condition and will require a transplant when she is older.

Before his successful transplant Olly, from Bessbrook, County Armagh, was continually fatigued and underwent up to 14 hours of dialysis every night while on a strict fluid intake restriction.

"We always knew Olly was sick," said his mum Dionne.

"If we hadn't have taken him to Daisy Hill Hospital for a blood test they told us he wouldn't be here, which is a scary thought.

"He cried from morning to night.

Olly after his surgery at Belfast City Hospital

"If he got about 15 minutes [sleep] that was it. There's nothing you could do to settle him.

"He cried, he was sore all over and dying of thirst but was only allowed 100ml of water every day.

"He didn't want to interact with other children, and was in a really bad way. Looking back now I think: 'How did we get through that?'

"The previous two Christmases he was on dialysis and he was tired and fed up. Now he's getting so much enjoyment out of all the toys and I can't wait to see his face this Christmas morning."

Olly's surgery was performed in Belfast City Hospital by surgeon Tim Brown, who admitted the operation was complicated.

"We're using an adult kidney and obviously that's a fair size compared to a child's tummy," he said.

"Finding somewhere to put it... the size of the vessels that we have to stitch the kidney onto are so much smaller, so it's always more stressful to get it right.

"But it's a real privilege to be able to take part in this family's journey.

"Kidney disease makes such a huge impact on children's growth, their development, their ability to eat and even attendance at school - so this is a winning lottery ticket for young Olly.

"It's the smallest transplant we have attempted in Belfast, it's early days yet but so far everything seems to be doing ok for him."

The Cartmill family put out an appeal on social media

Earlier this year, the Cartmill family issued a public appeal on Facebook for a new kidney for Olly, and were inundated with offers of help.

The volume of calls overwhelmed the Belfast City Hospital phone lines, causing the system to crash.

Eventually Olly's grandmother Michelle was found to be a suitable donor.

"I got a phone call to say I was a match and I couldn't believe it," said Michelle.

"I was delighted I could do that for my grandson, so it's an amazing feeling.

"It was really hard to watch him and not be able to do the things other three-year-old children would do, so to see the difference in him now is unbelievable."

Olly is looking forward to Christmas

Olly and Etta are the only two children in the UK who are known to have TTC21B, a rare condition which causes kidney failure.

Etta will need a new kidney but is not big enough yet for surgery.

"We actually were in hospital when we found out Etta had stage five chronic kidney disease as well," said their dad Neil.

"It's a full time job for the two of us looking after the two of them. We are in the hospital at least two or three times a week.

"We have one sorted out but now have a while to wait to get Etta sorted as well but hopefully we will get there.

"We are confident she will have a kidney transplant too."

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