SINGAPORE - Guardian angel, "kor kor", and yes, mad man.
Mr Lin Dilun, 27, has been called all that.
You see, he has done something extraordinary. Something that confounds even the experts.
After reading a story about a boy who had no kidney in The New Paper in 2010, Mr Lin made a monumental decision - he was going to donate one of his healthy kidneys to the complete stranger.
And after a two-year journey packed with interviews and medical tests, Mr Lin did just that two weeks ago.
He underwent a four-hour operation at the National University Hospital (NUH) to remove one of his kidneys.
Today, little Bryan Liu, 6, is recovering, with Mr Lin's kidney in him.
Mr Lin, an events consultant, has given the boy, who started Primary 1 this year, a new lease of life.
He says, in typically modest fashion: "I have something I don't need and someone needs it - it's perfectly logical to give it to him.
"The crucial thing is, if I give it away, can I still survive? If yes, it's no loss to me. It makes perfect sense."
Not so to some of his friends and relatives. They thought him mad.
Mr Lin is now back home in a three-room flat in Ang Mo Kio, while Bryan is still recovering in hospital.
Mr Lin's parents are divorced and his mother has remarried. He has an elder brother and two younger half-siblings.
The former Nanyang Polytechnic student describes himself as fun-loving.
But his act is all-loving: Organ donations are few. As of March this year, there are 448 patients on the national waiting list for a kidney transplant, said a Ministry of Health (MOH) spokesman.
Cases of living donors are rare. And donors are often relatives or people who know the patient.
MOH does not track the number of unrelated altruistic organ donors in Singapore.
When told that Bryan's donor is a Singaporean, renal physician Dr Akira Wu, 62, who has done at least 300 kidney transplants in 20 years, said it is the first case of a Singaporean altruistic donor he is aware of.
To prevent financial and emotional complications and potential abuse, by law, the donor and the recipient - or their families - are not meant to be in direct contact.
But if both donor and recipient agree to meet, they can do so.
Mr Lin and Bryan first met on July 23 - two days after the transplant - when, on Mr Lin's request, he was wheeled to Bryan's hospital bed.
Mr Lin's mother, Madam Serene Neo, 47, a housewife, accompanied him.
It was at this meeting that Bryan called him "kor kor" (elder brother in Cantonese).
Said Mr Lin: "Bryan started telling me what he wanted to do once he recovers. He wants to go swimming, visit Hong Kong's Disneyland and go on holidays."
He then introduced his mother to Bryan, telling the little boy: "This is Auntie. She gave me two kidneys so that I can give one to you."
Mr Lin said the little boy then thanked his mother too.
He said: "Bryan just brings joy to people around him. When we visited him, he was the one making everyone laugh and smile.
"For a boy who had gone through so much, he approaches life with a big smile. He is remarkable. He's fearless about life."
While the law provides for a donor's identity to be kept a secret, Mr Lin decided to "out" himself.
His reason is altruism. He wants to create greater awareness about live organ donation in the hope that more people would come forward to save lives.
He said: "We are less liable to do something if we do not know what it entails."
He hopes that by sharing his two-year journey, which culminated in the kidney transplant, potential donors are able to "put a name and a face" to a living example in Singapore.
"With proper information and explanation, I hope that anyone out there who may be hesitant about taking that step forward can find the motivation to do so," he says.
Mr Lin was discharged six days after the procedure and by the 12th day, he was taking slow walks around his neighbourhood.
Except for some lifestyle changes, like taking less salt, eating healthily and not taking certain painkillers, Mr Lin was told his quality of life should not change.
Before the transplant, he used to play football every week and paintball once or twice a month. He intends to return to the pitch in three months' time.
And as for Bryan, his mother said that he is doing very well - eating and sleeping well.
But life has changed for Mr Lin, even if he says he is still the same person he was before the operation.
His life has just become extraordinary.
The first step
THE FIRST STEP
It all started with a report about Bryan in The New Paper on June 7, 2010.
Mr Lin Dilun read about his plight then and started wondering if he could help.
A week later, on June 14, he read about how six readers had stepped forward to pledge their kidneys, but none was a match for Bryan's O+ blood type. He says: " I remembered thinking maybe I could help since I have O+ blood type."
So he took action - he looked up ways to contact Bryan's family and he found the Facebook page set up by a relative of Bryan's, called "A Kidney for Bryan, A Gift of Life".
He left an e-mail with his contact details indicating his intention to donate one of his kidneys. On the same day, Bryan's mother replied and forwarded his e-mail to the liver and kidney transplant office of the National University Hospital (NUH).
The next month, Mr Lin went for his first interview at the transplant office.
He was also given a 27-page binder with information on living kidney donation.
In it, he found answers to most of his questions. Was there a chance he could die? What lifestyle changes did he have to make? Would the procedure cause erectile dysfunction?
His motivation to donate became stronger as he found out more. He says: "There are more than 400 people on the waiting list. If nothing is done, they will die.
"I can't make a difference to everyone, but I can make a difference to Bryan."
Two months after his first interview, Mr Lin went for blood tests to ensure he was healthy.
He underwent tests to determine which kidney to donate - he donated his left kidney - while they kept the more active one for him.
By early last year, he was found to be healthy enough to donate.
Then Mr Lin had to undergo psychiatric assessments to make sure he was mentally sound.
The transplant office coordinators also met his family members - his mother and elder brother - three times to ensure that his family was supportive.
Around July that year, he met the surgeon, Dr Tiong Ho Yee, director of kidney surgery and transplantation in the NUH's urology department, who would be operating on him.
But there was one more hurdle - meeting the ethics committee who would decide whether the transplant was a go or not.
He met the ethics committee for the first time in October that year. But it wasn't a yes. Instead, he was asked to wait for another six months.
He was disappointed. He says: "I could wait, the transplant office people could wait. But we didn't know if Bryan could wait six months."
Why the wait?
In an earlier report, Professor A. Vathsala, who heads the adult renal transplantation programme at NUH, said the donor was given a longer cooling-off period than normal.
"We understand that this was to ensure that he was 100 per cent sure about the donation, given that there are no blood or emotional ties, and hence he has no control over the health of the donated organ or the recipient."
Mr Lin heard nothing from the transplant office until March this year.
After the six months were up, Mr Lin was asked in a second interview with the ethics committee in April if he had changed his mind.
His answer remained the same - he wanted to help Bryan.
The ethics committee finally gave the nod and the transplant was scheduled for July 4.
But he was told that the approval from the ethics committee would expire on the day of the transplant.
So, the transplant was pushed to July 21 while a third interview with the ethics committee was scheduled.
By then, the validity of the blood tests had expired. So he had to redo the battery of tests to ensure there was no change in his health.
For the repeat blood tests, 12 tubes of blood were taken from him at the same sitting to speed up the process. Recalling the procedure, he says: "I'm a big-sized guy. Losing a bit of blood is fine with me."
And so he met the ethics committee for the third time on July 5 and got the final go ahead. In all, Mr Lin has been in and out of NUH about 15 times.
Meanwhile, Bryan was battling with high blood pressure and infection of the peritoneum. He had to be warded about 20 times during the two years since his story first became public.
But Madam Ng got the long-awaited call came from the transplant office in May.
"We have found a donor," the female voice said.
Bryan's family did not know who it was, whether it was one of the several people who had come forward previously, or someone else.
But they remained cautiously optimistic as they feared the donor might change his mind. It didn't happen.
On July 20, Mr Lin was warded.
The next day, at 8am, on the operating table, the surgeon turned to him and asked: "You are ready to do this?"
His instant reply: "Yes."
He then felt the anaesthetic going through his body and the next thing he knew, he was in the recovery area.
Mr Lin was later moved to the high-dependency unit for a day before being transferred to the normal ward.
While still warded, Mr Lin received many visits from family and friends, some unexpected, including a pen pal he has never met.
He said: "I'm overwhelmed by the outpouring of love and concern."
10 hours of dialysis every day
HE ENDURED 10 HOURS OF DIALYSIS EVERY DAY
Little Bryan was born with only one kidney.
It was small and had abnormal tissues - and it failed completely by the time he was two.
His father, Mr Victor Liu, 50, a manager in a telco, and his twin sister Charmaine, couldn't donate their kidneys as they have different blood types.
His mother, Madam Serene Ng, 38, donated hers but it failed nine months later. It had to be removed in September 2009 because of a virus.
Bryan then depended on 10 hours of dialysis a day, a cocktail of medications and growth hormone injections to stay alive.
At just over a metre tall, Bryan's growth is stunted.
He is shorter than many of his peers, including his twin sister.
When Bryan runs, his legs bend outwards. He doesn't swim for fear of infection.
He wouldn't feel thirsty and used to drink just 300ml of water daily.
He was taking milk powder for babies as it is lower in potassium.
An excessive level of potassium in his blood could result in heart failure.
Despite this, Bryan is a bubbly, active boy, who is happiest at the playground. And thanks to his new kidney, he's going to get to spend more time there.
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