Six-year-old Queensland boy in limbo after critical bone marrow transplant left on tarmac at US airport

A Queensland mother is desperately hunting for answers after her sick young son's critical bone marrow transplant was left on the tarmac in the United States.

Shalyn Eggleton, whose six-year-old son Mateoh had been waiting for months for the marrow, says she's "really frustrated" and is living "in hell" while she tries to get the bottom of how such an unfathomable mistake could happen.

The family have so far been given no answers by officials on how long the transplant had been left at the airport for and are now waiting for the marrow - which is a rare match to Mateoh - to be sent to Australia, to see if it's still viable.

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"The biggest thing to understand is: how could something like a big medical protocol and procedure be left behind at an airport when it should technically be supervised 24/7?" Shalyn told Today.

"We have received no reasons, nothing, pretty much.

"I will be doing all that digging myself because it's unacceptable.

"He's fought three and a half years...and for someone to be so neglectful and just naive when it comes to such a thing like this.

"Like, this is what he's been waiting for and someone's just left it behind."

Mateoh suffers from chronic granulomatous disease, a genetic disorder which means his white blood cells are unable to fight off certain types of infections.

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He has an additional syndrome that causes his red blood cells to attack his body.

"Through the last 18 months, we trialled nine different things," Shalyn said.

"Like plasma, different haem therapy drugs, adult chemotherapy drugs, but nothing has worked.

"We were told at the end of last year I have to make the decision whether to do the transplant or not, knowing that it's our last option.

"And looking how well he is (there was) no way I could stop treatment.

"So my option was to go transplant, it did take a little bit to find a donor, our first donor actually rejected and declined...this donor has taken a while.

"This person in America has gone out of their way to go and be harvested, it's not affected me, it's someone else that has donated to Mateoh and now that's been left behind.

"It's a lot for us."

Shalyn said Mateoh is still on chemotherapy to "keep him going" while they wait for the transplant.

"That's how we prolong it at the moment, chemo," she said.

"All the blood we've been giving him, he has a significant iron overload.

"That's what we need. We need the transplant to try and move on and try and fix him, because it's unfair on him."

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