An NHS Trust has apologised to a transgender woman whose medical records were sent to another patient by mistake.

Imperial College Trust admitted it had breached patient confidentiality after records belonging to Sarah Preece, a patient undergoing gender reassignment surgery, were placed in the wrong file.

Ms Preece only learned of the mistake when another patient wrote to inform her that she had received files containing highly sensitive information, including details of her surgery.

In text messages seen by The Sunday Telegraph, the woman revealed she had been provided with Ms Preece’s “name and address... also that you may have changed gender”.

She added that the files showed “that you were unhappy with your treatment... and the fact that you had concerns about confidentiality".