Nasie Bayley has such a rare condition in her digestive system doctors consulted leading international specialists before operating.
And while the Whangarei 16-year-old's still having follow-up surgeries - only last week she had varices or veins in her stomach banded to stop internal bleeding - she is finally on the road to recovery.
Nasie has enrolled in one class back at Kamo High School and is focused on getting her life back to ordinary.
"It's been hard but I've just kept going," she said.
In June last year doctors at Starship Children's Hospital in Auckland discovered Nasie had a rare vascular malformation and was "bleeding out" from her digestive system.
"They hadn't ever seen it before," says Nasie's mother Melissa Bayley.
"There are a few cases worldwide that are similar, but none the same."
Nasie was having extensive blood transfusions as she'd used up the clotting factors in her blood, then had a massive haemorrhage last July which landed her in Starship's Paediatric Intensive Care Unit (PICU).
"There were 28 doctors and specialists in their trying to figure out what to do," Ms Bayley said.
"They booked her in for surgery, they decided they had better take it [the vascular malformation] out. In the meantime she was still having all these transfusions."
Doctors had readied themselves to operate and remove the malformation with a 10 hour surgery, but they had to cancel after they found blood clots blocking off a major vein.
"Because that was blocked it blew up the spleen, and from there it was like a domino effect - all of a sudden there were all these new things wrong."
With all these new challenges doctors had to rethink the surgery plan. In September a number of them flew to Boston and London to discuss her case with the world's leading specialists, Ms Bayley said.
"They came back with a plan to take out the spleen, take out the malformation - which meant they had to remodel all her large intestine."
"They'd said to us that the chance for Nasie to bleed out is high, but if we don't do anything she's going to bleed out anyway so it's a risk we were willing to take. They said that if at some point in the surgery she gets to the point they can't control the bleeding they pack it with gauze and bind her up and chuck her in PICU in a coma.
The surgery was successfully carried out at Starship last November. After the surgery Nasie required intravenous nutrition - "she hadn't eaten for months" - and the insertion of an ostomy bag.
She was allowed home on Christmas Eve and faces ongoing monthly surgery.
But Ms Bayley says that she is continuing to recover well. "Things are looking good."
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