Peggy Chu Sau-kwan is often heard on television purveying a message scary enough to make drug addicts wet themselves. Addicts, she warns in a government public announcement, have a bladder capacity only one-fifth of normal, so they need to go to the toilet every 15 minutes. 'That means when you take a bus, you need to get off every 15 minutes. Every 15 minutes ...' she intones. There is no one better qualified than Dr Chu, a senior urology doctor at Tuen Mun Hospital, to issue such a warning, because she discovered in 2007 the relationship between ketamine abuse and bladder dysfunction. 'I am merely recounting what my patients have been telling me.' Dr Chu this month received the Hospital Authority Outstanding Staff Award, given to employees demonstrating professional excellence. According to her research for the Narcotics Division, 30 to 40 per cent of ketamine addicts aged 15 to 30 had kidney dysfunctions. She will continue research in this area. Having entered the profession in 1988 as a surgeon at Queen Elizabeth Hospital, Dr Chu received urology training in 1996 and worked at the hospital for another 10 years before transferring to Tuen Mun Hospital. She splits her time between curing patients and doing academic research, attending conferences and advocating better training for medical staff. One of the activities she pushed forward was sending nurses to New Delhi for training. Having so many tasks at hand, Dr Chu said her family had complained. 'When I told my dad that I got the award, his first reaction was: 'Won't you be even busier?'' Even though she had made important discoveries, Dr Chu said she enjoyed curing patients more. 'Whenever I see patients going back to normal life, I feel very happy.' Looking back at her 21-year career, the case she remembered most fondly was an American tourist whose kidney suddenly failed on a flight to Hong Kong. 'His friend told him not to stay in Hong Kong's public hospitals,' the doctor recalled. 'But the patient was determined to finish his treatment here before going back to the US. He said he was deeply touched by our enthusiasm.'