Zavier Hull is "just like a normal 3-year-old", mother Danielle Simpson says.
Whanganui toddler Zavier Hull has “completely adapted” to his new life, nine months after being rushed to Auckland’s Starship hospital with failing kidneys.
In May, the 3-year-old was one of only five children in New Zealand aged 3 or under to be on dialysis, with a diagnosis of end-stage kidney disease.
Genetic blood testing on Zavier and his mother, Danielle Simpson, revealed something even rarer – he had occipital horn syndrome (OHS).
Simpson said she was a carrier of the condition, and Zavier and another of her sons had been diagnosed with it.
“It’s a connective tissue disorder. That explains a lot of his symptoms, like difficulty walking.
“Only around 35 people have ever been diagnosed with it.
“Specialists are asking me about the research I’ve done so we can put our notes together.”
Zavier’s kidney issues were first picked up after Simpson and father Matt Hull took him to a GP because of walking issues.
Simpson said specialists had yet to determine whether OHS played a part in a urethral blockage that caused Zavier’s kidney issues.
Health NZ Te Whatu Ora group director of Auckland operations Dr Michael Shepherd said OHS was caused by a change in a gene called ATP7A.
“People with OHS can have loose joints and skin, problems with the bladder and blood vessels, and small bony bumps at the back of the head called occipital horns,” he said.
“Bladder problems are common, but kidney failure is extremely rare, which makes Zavier’s case unusual.”
Shepherd said having a clear genetic diagnosis had helped the healthcare professionals involved provide the right care and support for Zavier and his family.
Simpson said Zavier had six nightly dialysis sessions a week, each running for close to 10 hours.
“It’s really opened our eyes to how incredibly resilient kids are.
“Thankfully, he’s completely adapted to it.”
She said she and Hull were matches for a kidney transplant, and the procedure was a possibility in 2026.
“It has to go to a specialist, who determines if a transplant is the best idea for the child.
“That should be happening this month, then we’ll have a date.
“Things can change, though, because lots of people need operations and transplants and things like that. But the ball is definitely rolling.”
Simpson said Zavier and her other son would be monitored for the rest of their lives due to OHS.
Zavier’s kidney function was 8% when he was first at Starship.
The contrast between then and now was hard to put into words, she said.
“Before dialysis, he was never able to run. Now, I’m having to say ‘Stop running in the shop’.
“Renal specialists are always laughing because he is so full of energy.
“He’s just a normal 3-year-old.”
Simpson said she hoped to link up with others who had been affected by OHS.
“There is a man called David Rose in the UK and I’ve made contact with him. That has been incredible.
“But it would be nice if we could find someone in New Zealand or Australia, somewhere closer to home. Just someone to relate to.
“The chances are slim but you never know.”
Rare Disorders NZ chief executive Chris Higgins said the organisation had more than 150 support groups in its collective but none specifically for OHS.
“With over 7000 rare disorders, there are many disorders we do not come across until somebody contacts us.”
Higgins said the organisation was not aware of specialists with expertise in occipital horn syndrome.
However, it was working with Health NZ Te Whatu Ora on “a leadership and co-ordination mechanism” to improve access to expertise, information and support for those affected by rare disorders.
“The Ministry of Health’s Rare Disorders Strategy, released in 2024, also stipulates the need to provide health practitioners with more learning opportunities on rare disorders to improve their awareness and knowledge, and Rare Disorders NZ will be working closely with the Ministry to monitor progress on this priority.”
A Givealittle page for Zavier and his family can be found at givealittle.co.nz/cause/zaviers-give-a-little.
Danielle Simpson is walking 120km this month to raise money for Starship.
Donations can be made at www.kilometresforkids.org.nz/fundraisers/daniellesimpson.
Mike Tweed is a multimedia journalist at the Whanganui Chronicle. Since starting in March 2020, he has dabbled in everything from sport to music. At present his focus is local government, primarily Whanganui District Council.