A RENAL specialist will have to explain to the Medical Council's preliminary investigation committee (PIC) why he referred a patient to China for a kidney transplant that might not have been necessary. Sources close to the council said the doctor, who cannot be named for legal reasons, would be asked to explain his conduct to the committee when it met in December or January. It is believed the Attorney-General's office has been asked to study the claims about the doctor, who is alleged to have committed professional misconduct and disregarded his responsibilities towards one of his patients. The patient, known as Mrs Mak, reported the doctor to the council last month. The doctor referred the housewife to the First Affiliated Hospital of the Sun Yat Sen Medical University in Guangzhou in April 1991 for a kidney transplant. But Mrs Mak suffered a violent and immediate rejection of the new kidney, which had to be removed. She was later told by leading Hong Kong doctors the operation might not have been required, because she did not even need kidney dialysis at the time of the referral. Medical records show her level of creatinine, or the accumulative metabolic waste product which her kidneys failed to get rid of, had not reached a point where she would require dialysis. More importantly, she did not need dialysis more than one year after her failed transplant in China. Mrs Mak's case, featured in the launch issue of the Sunday Morning Post Magazine , sparked a debate on transplants in China, which most Hong Kong doctors feel amounts to organ trading. Legislator Dr Lam Kui-chun is believed to have written to the Medical Council urging action. The doctor who referred Mrs Mak to China remains adamant he acted in her best interests and referred her to China because her creatinine level had risen sharply. He claimed Mrs Mak had said repeatedly she wanted to avoid dialysis, and that at the time of the referral her kidneys were approaching a stage where they would stop working. He said any specialist would have recommended a transplant under the circumstances. When told of the Medical Council's decision yesterday, the doctor said: ''It is up to them to refer [me to the PIC]. There is nothing I can do. ''I have done nothing to be afraid of.'' The doctor can make either a written submission or appear in person before the PIC, which will decide whether an inquiry will be held to look into the allegations.