In short:

The Queensland coroner has released a report on the findings of a six-year-old boy's death, after suffering a cardiac arrest in 2024.

The coroner found the boy had a severe vitamin C deficiency which was deemed to be the most likely underlying factor that lead to the cardiac arrest.

As his condition deteriorated, his family were told "severe life-threatening scurvy seemed a likely unifying diagnosis".

A coroner has found scurvy to be the "most likely underlying factor" in the death of a Queensland boy with Down syndrome.

Six-year-old Connor Dean died in the Queensland Children's Hospital on August 10, 2024, after his heart stopped following a general anaesthetic, and he experienced a severe brain injury from a lack of oxygen.

He weighed just 14.1kg when he died.

In non-inquest findings, Deputy Queensland Coroner Stephanie Gallagher, backed a forensic pathologist's opinion that Connor died from "hypoxic ischaemic encephalopathy due to cardiac arrest following general anaesthetic, in the setting of vitamin C deficiency".

She found Down syndrome was a "contributing factor".

"Although the precise mechanism leading to the cardiac arrest could not be definitively determined, the treating clinicians and forensic pathologist considered vitamin C deficiency to be the most likely underlying factor," Ms Gallagher wrote.

Connor had surgery as a baby for a heart defect, was developmentally delayed and communicated using "mostly single words".

He walked and ran with a "wide-based gait".

About a month before his death, his parents reported he started walking with a "shuffling gait which progressed to limping" and eventually he refused to weight bear.

Scurvy a 'likely unifying diagnosis'

He was admitted to the Queensland Children's Hospital for investigation, which included a scan under general anaesthetic.

He went into cardiac arrest following the scan and was revived after 8-10 minutes of cardio-pulmonary resuscitation (CPR).

As his condition deteriorated and opinions were sought from various specialists, his family was told "severe life-threatening scurvy (vitamin C deficiency) seemed a likely unifying diagnosis".

His parents said they were unaware of their son's Vitamin C deficiency until after his cardiac arrest.

Connor's paediatrician, who had about 20 years' experience in the specialty, told Ms Gallagher in a statement he had "significant concerns regarding Connor's growth and nutritional deficiencies for a long time".

In November 2023, he said he discussed with Connor's mother that the boy's diet was inadequate to meet his vitamin and mineral requirements" but he believed his needs were being met with his intake of multivitamin supplements.

During Connor's admission just before his death, his mother advised he was taking a multivitamin and his immunisations were up to date.

Connor's paediatrician told the coroner he was concerned the product, which was not named in Ms Gallagher's findings, was available in Australia.

"I believe that it is misleading to call this product a multivitamin when it misses essential vitamins such as Vitamin C," the medical specialist said.

Given the absorption of plant-based iron is greatly enhanced by Vitamin C, he said it was "illogical" to have an iron-containing product in combination with multiple vitamins, but not Vitamin C.

"It is my clinical opinion that Connor would not have had Vitamin C deficiency, and the clinical features of scurvy that lead to his death, if he had been taking a different multivitamin that contained Vitamin C,"the paediatrician said.

But the manufacturer of the multivitamin told Ms Gallagher in response: "Multivitamin products do not generally contain all essential vitamins and nor are they indicated for treatment of a severe deficiency.

"They are indicated to help supplement when dietary intake is inadequate."

The manufacturer told the coroner that given "the apparent lack of monitoring of Connor's Vitamin C deficiency prior to his arrest, there is no basis on which to draw the conclusion that" the multivitamin contributed to Connor's death.

"Any such uncertainty should not be resolved by the adoption of a single clinical opinion by a non-independent clinician in the circumstances," the manufacturer wrote.

Ms Gallagher did not address the multivitamin issue in her conclusions.

"The evidence establishes that Connor Dean had severe Vitamin C deficiency, with associated … features consistent with scurvy, and that he suffered a cardiac arrest following the administration of a general anaesthetic," she wrote.

"I extend my condolences to Connor's family and loved ones for their loss."