Her raunchy performance of Feeling Good left the judges stunned last night.
But 26-year-old Kitty Brucknell has reportedly voiced fears that the stress of competing in the X Factor could aggravate a debilitating illness.
The singer is said to have nearly died last year due to a severe case of Guillain-Barre syndrome, which attacks the nervous system.
Scroll down to see Kitty's rendition of Feeling Good...
The blonde gave her saucy rendition of Feeling Good in a custom-made leotard with flashing lights.
Before taking to the stage, Kitty admitted: 'I couldn’t pay my rent because I bought this costume, it was over £2000.'
But all of this effort may yet take its toll on the hopeful.
According to The Daily Mirror, Kitty told a friend: 'I know X Factor isn’t the best thing to do after what I have been through. Stress and strain could kill me, if it affects my immune system.'
The friend told the Mirror: 'Kitty’s an emotional person and really throws her all into performing so the X Factor has already been a very draining experience for her.'
'The stress is only going to increase and she’s only going to get sicker,' they added.
'No one gets through to the later stages of the competition without being subject to stringent medical checks,' divulged the senior source.
Kitty collapsed on the stage in tears last night when she heard that she'd made the final 32.
'The whole experience has been extremely tough on her and if it gets really bad, I’ll have no hesitation in telling her to pull out,' she admitted.
Kitty’s mentor Louis Walsh said: 'She’s very emotional and very ambitious. She will do anything to be famous. She will do anything I want her to do, and she will have a big, big following.'
'She sounds great, I can’t stop looking at her, and she is fascinating,' commented Gary.