Tommy Hilfiger's daughter says Lyme disease has ''taken over every single cell'' in her body and brain.

Ally Hilfiger - the oldest child of the fashion icon - has admitted her battle with the debilitating illness has left her feeling like an ''80-year-old woman'' after doctors failed to spot the infection for 14 years after she contracted it.

Speaking to the Daily Mail newspaper, she said: ''I couldn't put lotion on my legs because it felt as if I was being beaten with a baseball bat. I was like an 80-year-old woman. It had taken over every single cell in my body and in my brain.''

The 30-year-old fashion heiress believes she was plagued with the disease after she was bitten by a tick as a child.

The illness, which is passed on to humans via an infected tick, left Ally in ''excruciating'' pain, which led to her relying on a walking stick and struggling to sleep at night time.

Doctors initially thought Ally's symptoms - which included painful joints, headaches and a high fever - were pointing towards arthritis, a sever case of flu or growing pains.

However, Ally was adamant her symptoms were caused by something more sinister and sought a second opinion from a psychologist, who diagnosed her with the chronic disease.

She said of her diagnosis: ''This was like winning the lottery for me. I was so relieved.''