The management of Jan Axel Pettersson's care at the Mersey Community Hospital in the northwest, where the 71-year-old died three years ago, was described as poor in findings published this week.

Mr Pettersson was first admitted to the hospital in October 2017 with a fever and unsteady gait and died about a month later.

Preliminary autopsy results suggested Mr Pettersson died of heart failure, but additional toxicological tests discovered he had an unexpected fungal infection in his brain and lungs.

"The infection which caused Mr Pettersson's death was able to have been treated - had it been diagnosed," Coroner Simon Cooper wrote.

"His death was unnecessary and avoidable."

An x-ray taken when Mr Pettersson first went to hospital showed a mass in his right lung, which was noted in medical records as likely to be malignant cancer.

But a Tasmanian Health Service report "expressly accepted" that no malignancy could be found and that he had been misdiagnosed, Mr Cooper wrote.

The report acknowledged there were "missed opportunities to explore other diagnoses and initiate appropriate investigations".

"The management of Mr Pettersson at the Mersey Community Hospital was poor," Mr Cooper wrote in his conclusion.

"No appropriate management plan for his lung lesion was developed.

"There was clear evidence of intracranial involvement in his condition but that evidence was not investigated fully or early enough."

Mr Pettersson, described as a healthy and active man, had begun experiencing dizzy spells after falling off his bike on a trip to Sweden in June 2017.

Mr Cooper passed on his condolences to Mr Pettersson's family.

Australian Associated Press