Andrew stood on a gumnut in his backyard and a month later needed to have his leg amputated

A man is lucky to be alive after stepping on a gumnut and developing an infection so serious that he ended up having a leg amputated.

Andrew Trigg, 40, stepped on the gumnut at his home in New Lambton Heights, Newcastle, in the NSW Hunter Region, on May 12.

A seed became lodged under the skin of his right foot and festered over the following month, becoming so bad that he was unable to move or eat.

Mr Trigg was eventually taken to hospital where he was diagnosed with sepsis.

Surgeons first amputated his toes but later realised the infection had spread, forcing them to remove the lower half of his leg.

The 40-year-old was shocked at how a seemingly innocuous moment could lead to a life-threatening illness - but is determined to overcome the setback.

'This isn't going to define me. It will change me, but not define me,' he said.

Mr Trigg said he did not think anything of the wound immediately after he stepped on the gumnut.

The seed had created an ulcer and after he and his wife Kylie cleaned and dressed it every day, his foot seemed fine. 

But a month later Mr Trigg had a fall at home, with his wound taking the brunt of the force.

Within a couple of days he had a fairly 'sizeable bruise' and there was an odour coming from his foot.

'That's when I knew I needed antibiotics,' he told Daily Mail Australia. 

After obtaining a script from a doctor online because he 'couldn't move', he started the five-day course - but noticed the inflammation had started spreading up his leg.

Mr Trigg said he was feeling unwell and could only hold down a slice of toast, some grapes and 'litres' of water over the next week.

His wife insisted she drive him to John Hunter Hospital after his pain became worse. 

After some initial tests, a nurse broke the news to him that he was a diabetic - a condition Mr Trigg had no idea he had been living with.

The nurse explained diabetes could make infections even more problematic. 

After a day of taking blood samples and being observed by doctors, Mr Trigg was told by specialists he would need his big toe removed because he had sepsis.

Sepsis is the life-threatening response a person's body has to an infection, and starts attacking tissue and organs.

'They told me the hope was in removing [the big toe] they would use the skin left over to wrap - and hopefully keep - the rest of the foot,' Mr Trigg said. 

But later that night specialists delivered a shocking blow to Mr Trigg, informing him there had been no 'good tissue in the area' and they would need to 'take a couple more toes', after concluding his foot didn't 'look good'.

Despite the life-changing operations, Mr Trigg hadn't lost his sense of humour, saying: 'They took the two toes at the end, leaving the ones in the middle. It was like I was wearing a pointy-toed heel.' 

Shortly after the operation, the doctors again delivered some tough news to Mr Trigg and his wife.

'They said even though the amputation of my toes was a success, the infection had spread across my foot and there was no good tissue,' he said.

'The doctors said my options were to keep chopping the foot back bit by bit but the infection could keep spreading. Or I could leave it and die. 

'The final option was to get an amputation of my lower-leg under my knee and give myself the best chance.

'I haven't had trouble dealing with the amputation because the only other option is death.'

Despite Mr Trigg's ordeal, which also involved an additional surgery two days later to shape his limb, he wants to get the message out to people, especially men, not to delay treatment.

'Don't be too proud to get help. As soon as you see something different - a mark, a cut, a lump - go straight away to a doctor,' he said. 

'Don't tell yourself, "It will clear itself up, it'll be OK." You can't risk it.

'The doctors told me if I'd waited a couple more days I could have been dead or at least in ICU fighting for my life.' 

The salary packaging consultant, whose doctors have said is 'still not out of the woods' and has 'a long way to go', has now exhausted the last of his leave and has no pay coming in.

His wife of 14-years, who is a casual aged care worker, has no leave entitlements. She is now doing half days so she can be with her husband daily.

'I'll be in hospital for at least a few months for rehab. The doctors told me being able to hop, swivel and pivot is months down the track, as is a prosthesis,' he said. 

Mr Trigg said he would be in a wheelchair for months and the couple's rented home would need some modifications. 

A GoFundMe has been set up by their good friend Kerrie Stephens to help with the couple's ongoing expenses such as rent, specialist medical bills, modifications to their car and suitable accommodation.