Dr Allan Cala gave evidence on the second day of the inquest into the death of Luca Raso, who died in February, 2017, of peritonitis secondary to a ruptured gangrenous appendicitis.

Luca died on the way to hospital after he collapsed, following a week of illness that included vomiting, diarrhea, lethargy, loss of appetite and an instance of vomiting brown liquid that has been described as looking like "Coca Cola syrup".

In the week before his death, Luca's family twice took him to see Dr Paul Bilokopytov at one of Bay Medical Group's general practice surgeries for assessment - with the doctor on both occasions telling the family the 13-year-old had viral gastroenteritis.

Luca's mother, Michelle Degenhardt, also called the surgery on two occasions out of concern for her son.

Dr Cala told the inquest on Tuesday the condition that claimed Luca's life was bacterial, rather than viral.

He said the autopsy showed no evidence that Luca had gastroenteritis in the days before he died and Dr Bilokopytov's clinical notes were incompatible with what was found during the autopsy.

But Dr Cala said Luca's condition was rare.

"I don't believe most GPs [general practitioners] see people with this kind of condition regularly," he said.

"It's really quite rare."

The inquest, under State Coroner Teresa O'Sullivan, is expected to run until Thursday.

Dr Bilokopytov is also due to give evidence on Tuesday.

More to come.

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