A MAN whose body was discovered in a canal died after collapsing due to a rare and undiagnosed lung disease.

Peter Grant, who was found dead in the Manchester, Bolton and Bury Canal near his Radcliffe home on January 24, was suffering from pulmonary alveolar lipoproteinosis, an inquest heard on Tuesday.

The disease caused him to collapse into the water near Withins Bridge due to respiratory failure as he was walking back to his Farcroft Avenue house in the early hours of the morning.

His mother, Patricia Grant, told the inquest in Heywood that, before his death, the 48-year-old was “the happiest he had ever been”.

The Manchester City fan, who regularly walked his dogs along the canal path, had thought he was suffering from a chest infection at the end of 2015, but did not see a doctor and put his symptoms down to years of smoking and working with chemicals.

It was initially thought that Mr Grant, who was a laboratory manager at Stoneclough adhesives firm ITAC, had either drowned or succumbed to hypothermia, but a pathologist dismissed both of those theories.

Dr Paiva Correia said: “With this disease, the patient can have very few symptoms and then suddenly collapse.

“The symptoms two months before his death were probably due to the disease and not a chest infection. If he had had an x-ray then it could have been diagnosed.”

Toxicology reports showed that Mr Grant’s blood alcohol level was high after attending a party at a friend’s house with his partner, Deborah, but not high enough to kill him.

He had walked her home at around 2.30am before setting off along the canal path towards his house as he wanted to check on his dogs.

The pathologist added that the level of alcohol in his system would have impaired his coughing reflex, contributing to his death.

Fatty liver disease and hypertensive cardiomyopathy were also cited as contributing factors.

His body was discovered by a passerby at around 8am and was formally identified by his girlfriend later that day, after she had gone out to walk her dogs in the hope of meeting up with him on the canal path.

Mr Grant, one of five children brought up in Manchester, was described as a quiet, sporty man, who enjoyed swimming as well as playing football and cricket.

The family added that they wished to thank ITAC for their help and support over recent months.

Recording a conclusion of accidental death, Michael Salt, the assistant coroner, said: “The pathologist has explained that this is quite a rare condition that wasn’t evident to the naked eye but was under the microscope.

“It was something I had to look up myself as to its effects and how it comes about.”

He added: “There is nothing to suggest he was in anything other than a very positive frame of mind and he had made positive plans for the future.

“I pass my condolences onto the family members.”