A NORTHERN Territory holiday could cost a British tourist his kidney after he was bitten by a venomous spider in central Australia.

Alex Cann, 39, was bitten by the spider while touring near Alice Springs last month.

It wasn't until after he had boarded a plane back to London he realised the bite was serious.

Reports out of the UK last night said Mr Cann was bitten by a male brown tree spider, but local experts suggested it was more likely he was bitten by Australia's notorious redback spider.

Mr Cann, from Camden, North London, said he had just pulled a pair of trousers out of his suitcase when the spider jumped out and bit him on the knee.

"I didn't think much of it when it bit me. It just ran across the room,'' he told Britain's Daily Mail newspaper.

The 39-year-old electrician finished his Territory holiday, but two days after his return to England he noticed the bite marks on his knee starting to swell.

"I felt really dizzy, hot and nauseous,'' he said.

Mr Cann checked into a London hospital where he spent three weeks as baffled doctors tried to find out what was wrong with him. They eventually found a growth on his kidney which they believe was caused by the spider bite.

The bite of some spiders -- including the redback and the brown recluse spider -- can cause renal problems.

Mr Cann will find out today if his kidney has to be removed.

"I'm getting anxious about it now,'' he said.