WARNING: Graphic images

A man is speaking out to warn others after he was left fighting for his life due to his 'harmless' habit - of biting his NAILS.

Steven MacDonald, 48, was rushed to hospital just days after noticing his left index finger had become infected.

It swelled up and turned green with puss - after he'd been nibbling his nails.

The former postman - who has been a nailbiter all his life - was initially given magnesium sulphate by a pharmacist in order to cure it.

But his finger continued to balloon and just four days later his fiance, Karen Peat, 47, noticed a rash on her partner - running from his finger up his forearm.

Glasgow Times: Steven MacDonald contracted an infectionSteven MacDonald contracted an infection

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Karen rushed Steven to University Hospital Monklands, Airdrie, North Lanarkshire, Scotland, where the couple found he had a severe case of paronychia - an infection of the skin around the fingernail - which was spreading and medics performed emergency surgery to save his life.

Mum-of-two Karen, a care worker, from Coatbridge, near Glasgow, Scotland, said: ''At first we weren't that worried as he'd had little swellings before where he'd been nail biting, but when it kept getting worse and then he showed me the rash, I really started to panic.

''I knew it was quite serious then so I rushed him into our local hospital. The doctor took one look at it and he was whizzed right through the A&E queue.

''After giving him a strong shot of antibiotics they told us we'd need to go straight to Glasgow Royal Infirmary for emergency surgery.

''They told us that if we'd left it even a few hours longer he might have been dead.

''It was horrible to hear, I was so scared.

''I've told him he's never biting his nails again, it's just not worth it.''

Steven was admitted onto the plastic surgery ward, at Glasgow Royal Infirmary, on 6th January and within an hour was in surgery, under general anesthetic.

Glasgow Times: Steven MacDonald and fiance KarenSteven MacDonald and fiance Karen

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After a successful two hour operation to remove the infected flesh, Steven was kept in for observation for four days.

Despite the possibility that his nail might never grow back, Steven - a dad to one 12-year old daughter - remains positive.

He said: ''This ordeal has taught me a huge lesson, to any nail biters out there, please just pull your finger away from your teeth!

''I'd never had a problem like it before but it left me seriously considering life and death.

''I was quite jokey about it until I came around from the operation and realised what a close call it had been.

''I've been tempted to bite a few times since, as it's been a habit of mine for so long, over 50 years, but I've told myself not to.

''It's weird now that I'm not nibbling away at them, they're actually growing really fast.

''I keep joking that I might need to get myself down the salon for a manicure!

''But seriously, I really cannot thank the NHS enough, they reacted so fast, it was incredible''.

Glasgow Times:

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The couple - who met at school and who got together three years ago - were initially not worried when Steven's finger became red and itchy.

But after noticing it going green and swelling up, on Friday 3rd January, Karen insisted on taking her fiance to the local pharmacy, in Whiffet, Coatbridge, Scotland.

The pharmacist wasn't too concerned and suggested they purchase magnesium sulphate - which can be used to draw out splinters, pus or infection from the skin.

When the finger continued to swell the loved up pair went to a different chemist, in Coatdyke, near Glasgow, where the 'worried' pharmacist booked them an out of hours appointment at a doctors surgery in Airdrie, North Lanarkshire, Scotland.

Steven said: ''We went along later that afternoon to the emergency GP appointment, but the doctor wasn't that worried but did suggest it needed to be lanced and properly cleaned out.

''He wasn't able to do it then and there so suggested we go to hospital to get it sorted.

''He made a call to University Hospital Monklands but they said it might be an eight or nine hour wait and so we decided to go up there first thing the next morning.

''But when I got up the next day there was a rash all up my arm, coming from the finger, it was a bit like sunburn...

''I didn't think much of it but Karen seemed quite worried so we rushed into A&E.

''From there it was all quite a blur as a nurse came to look at it and rushed me into a room.

''A doctor then gave me antibiotics and sent me straight to Glasgow Royal Infirmary for surgery.

''In the cab over there, it was only 15 minutes but it felt like hours.

''I could tell Karen was really anxious but I wanted to stay positive and so was laughing and joking around with the taxi driver.

''Looking back now I just didn't realise how serious it was.''

After five days in hospital, Karen could finally bring her partner back home to recuperate.

She said: ''It was so good having him home again, even if his finger does look all mangled up.

''He's really been so brave about it all.

''I was especially worried because I'd been widowed at a young age after my husband, Alan, was in a bad house fire.

''In a weird twist of fate, Alan actually died on the same ward that Steven was admitted to.

''It felt like deja vu, I was terrified to lose another good man in that place. Thankfully he's right as rain now and we're finally planning the wedding.''