An underage girl in Hong Kong is seeking discretion from Hong Kong's Hospital Authority to allow her to be tested as a liver donor for her dying mother, who is suffering from acute liver failure.

The girl, 17, identified only as Michelle, is an agonising three months short of turning 18, the legal age to be a living donor for her mother, who is suffering from acute liver failure, the South China Morning Post (SCMP) reported on Wednesday (April 12).

The mother, Ms Tang Kwai Sze, 43, is currently warded at Queen Mary Hospital's intensive care unit.

The window for Ms Tang's liver transplant will lapse in a few days, prompting Michelle to embark on a heart-wrenching campaign to persuade the authority to make an exception, according to the Hong Kong Economic Journal.

"Time is running out... I feel worried and depressed," said Michelle, who has sent letters to the Hospital Authority with the help of a patient organisation, Hong Kong Patients' Voices, to seek discretion in carrying out tests on her, the SCMP reported.

Mr Alex Lam, chairman of the patients' concern group, felt a judicial review of the Hospital Authority's decision would be considered if Michelle was deemed mentally and physically suitable to be a donor.

This means she would have to be tested for genetic compatibility and if she carries any infections. Michelle would also need to be assessed to determine if she is fully cognisant of the risks involved as a donor.

Mr Lam's group hopes to use the basis of human rights to argue against the Hospital Authority's action, and to start a debate on how to strike a balance between child protection and right of survival, the SCMP said.

However, University of Hong Kong medical law don Terry Kaan said a judicial review would be valid only if the Hospital Authority's decision was proved to be discriminatory for the wrong reasons.

He said the court would have to look beyond specific cases and assess if the law - the Human Organ Transplant Ordinance - was unlawful.

It is understood that Michelle has been declared mentally mature for the transplant by an external clinical psychologist, though it remained unclear if she was genetically suitable to be a donor for her mother.

Speaking on a Radio Television Hong Kong programme, Civic Party member Kwok Ka Ki, who is also a doctor, said the chances of Michelle succeeding in her bid are slim as the Justice Department would have to grant an exemption to conduct an illegal operation.

But Mr Kwok added that he also felt Michelle's mother would not be able to wait another three months for Michelle to turn 18, due to her critical condition.