THE Crown Office has concluded that a rare fungal infection did not contribute to the death of a grandmother treated at Glasgow's superhospital.

Prosecutors said Mito Kaur died as a result of flu and that this was "likely unavoidable".

The health board said the source of the infection remains unclear.

The 63-year-old was one of two patients who tested positive for mucoraceous mould, a type of fungi, at the Queen Elizabeth University Hospital in January.

The other patient was discharged from hospital but Mito, who had been diagnosed with pneumonia, died in February.

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Her family said influenza had been found in her lungs and that she had initially recovered after receiving antibiotics.

However, they said she subsequently deteriorated following the mucor infection and ended up on life support with brain swelling. She died in February.

Her death was subsequently reported to the Crown Office.

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In a statement, NHS Greater Glasgow and Clyde said: "The Procurator Fiscal (PF) has concluded that the cause of death was infection with Influenza A & B.

"The PF also stated that mucoraceous mould, while present, did not contribute to the death and as such the PF also concluded that death was from natural causes and was likely unavoidable.

"During the Incident Management Team investigations there was a number of areas inspected for sources of mould with nil found and validation results were satisfactory.

"The hypothesis remains unclear and there were no further infection control investigations required at that time.

"If there had been an ongoing unidentified source we would have expected to see more patient cases."