When a heavily pregnant 38-year-old Madam Yow Sok Fun was preparing for the birth of her second child in 2009, she was slapped with a piece of news that she was not prepared for. Doctors told her that she had end-stage renal failure and needed dialysis. Soon after the birth of her second child, she was put on a thrice-weekly dialysis regime.
Her family explored the option of living donor kidney transplant as dialysis is not a long-term solution to her problem. Besides, patients who are put on the waiting list for deceased donors generally have to wait as long as nine years. For Sok Fun, the possibility of finding a compatible donor is nearly impossible because of her condition. So in January this year, Sok Fun got a new kidney from her 35-year-old brother, Mr Yow Kok Kheong.
You may think this was just one of the many kidney transplants performed in Singapore, except that it was not. The transplant almost did not happen. Kok Kheong was actually not a compatible donor as they do not share the same Human Leukocyte Antigen (HLA). HLA are proteins found on the surface of the white blood cells and other tissues in the body. In other words, they are not a “match” since their tissues are immunologically incompatible with each other. Furthermore, these differences led to Sok Fun having too many antibodies that could cause immediate rejection of the kidney if they were not removed.
To detect those antibodies, a T-cell cross-match test is performed. In normal circumstances, a positive T-cell cross-match test would not allow a transplant to proceed as doing so would lead to immediate rejection and loss of the kidney. The patient would then have to find another living kidney donor where the T-cell cross-match test would be negative or be placed on the waiting list for a kidney from a deceased donor. However, the latter would be an unlikely possibility as the presence of many antibodies would make it difficult to find a compatible donor.
The new treatment protocol
Thankfully, a team of SGH doctors from the Departments of Renal Medicine and Urology found a solution. They created a treatment protocol to remove the antibodies found in Sok Fun’s blood and allow for the kidney transplant to take place.
“As part of the Academic Healthcare Cluster, we want to offer the best treatment we could for our patients and when there is none, we create one based on treatments that have been proven to work overseas. This new treatment protocol will give hope to many other patients who are faced with the same problem like Sok Fun,” said Dr Terence Kee, Director, Director, Renal Transplantation Programme and Senior Consultant, Department of Renal Medicine, SGH.
To condition her body for the new organ, Sok Fun received monthly doses of intravenous immune globulin (IVIG), a blood product, for three months to reduce her high levels of antibodies against HLA proteins. She then went through alternate day plasmapheresis for three weeks where blood from the body enters a filter to remove the remaining antibodies before returning it to her.
Another cross-match test was then done. This time, the level of antibodies in her body was low enough for Sok Fun to undergo the transplant and receive a kidney from her brother in January 2013 using standard immunosuppressive drugs. Sok Fun did not suffer any major complications and shows no signs of rejection. The siblings are recovering well and are back to work full-time.