The incompatible blood-type kidney transplant was a surgery doctors avoided, as the patient's blood contained antibodies that reacted to the donor's blood type. If the blood types of patients and donors were different, the antibody reaction immediately causes the patient’s body to reject the transplant and prevents a successful operation.

However, recent advances in incompatible blood-group kidney transplants have made the practice available for many people. In Korea, such advances were especially important as the nation lacked kidneys that matched patients' blood types due to a small pool of donors.

Incompatible blood-type transplants now account for nearly 40 percent of the total kidney transplants here. Professor Yang Chul-woo of the Department of Nephrology at St. Mary's Seoul Hospital is one of the frontrunners.

"Incompatible blood-type kidney transplant has increased three to four times over the past decade, which indicates Korea is a very dynamic country regarding organ transplant," Professor Yang said in a recent interview with Korea Biomedical Review. "Even though we could do a blood-incompatible transplant, we were quite hesitant in the past due to concerns about rejection that could occur after any transplant regarding blood-type incompatibility."

However, Korea was short of donors, forcing hospitals to turn to incompatible bloody-type transplants to resolve the issue, he added.

Yang cited the “Egg of Columbus theory” in explaining the nation’s first successful incompatible blood-type kidney transplant in 2009. The Egg of Columbus theory refers to a brilliant idea or discovery that seems simple or easy after the fact.

"There were a lot of people who wanted to donate but couldn't because of blood type incompatibility," he said. "With the advancement of the surgery method, however, few hospitals refuse incompatible blood-type transplants now."

Particularly, transplants between husbands and wives have increased a lot, he added.

Yang noted that such changes are significant as Korea has become a nuclear family country, limiting transplants among family members.

Similar results regardless of blood types

Some patients still worry about their bodies rejecting the transplant due to a mismatch in blood type.

However, Yang stressed that patients should not feel worried, saying that his team has confirmed that there are not many differences between the two groups after a decade of conducting incompatible blood-type transplants.

"Especially for a short period of a year or two, the prognosis is almost the same. Foreign and local data show that there is no big difference in the long run, too," he said. "Therefore, it is more of a question of how to manage incompatible blood-type transplant patients during the first year or two to minimize the difference with patients who undergo same blood-type transplants."

Yang said that St. Mary's Hospital has managed transplant patients well, so that there is not much difference between the two groups even after 10 to 12 years.

Behind the excellent record is the hospital’s division of labor system, in which one team conducts incompatible blood-type transplants, and another team performs post-operation management.

"When we treat an incompatible blood-type transplant patient, we have a surgical team that performs surgery, and then there is an internal medicine team that manages the patient after transplantation," he said. "While many hospitals do not have separate wards for transplant surgery and general surgery patients, St. Mary's has a separate intensive care unit for transplant patients."

Yang stressed this is important as incompatible blood-type transplant patients are more susceptible to infections.

"Many patients ask us how long the transplant will last," he said. "We replied that our hospital was the first in Korea to conduct the incompatible blood-type transplant and have the longest surviving patient. Therefore, it is a hospital that patients can trust more than any other hospital."

Due to such a high level of performance, medical professionals from other countries often visited St. Mary's Hospital to learn its know-how, including patient management and the use of immunosuppressants.

"The number of doctors visiting the hospital to obtain our know-hows has fallen due to the Covid-19 outbreak. Instead, foreign patients who need a transplant but cannot go back to their countries due to the pandemic visit our hospital to consult receiving the transplant," he said. "Such patients include those from the Netherlands, Japan, Mongolia, and China."

Winning recognition at home, abroad

Yang also noted that St. Mary's treatment method had received recognition abroad as well.

"When our patients go abroad, I get to hear reviews from foreign doctors about the overall management of incompatible blood-type transplant patients from Korea," he said. "Fortunately, they generally give very good reviews. Conversely, people who come to Korea after receiving a transplant in a foreign country also show satisfaction after receiving additional treatment at our hospital."

Yang pointed out that desensitization treatment – to see whether or not the tissues fit when transplanting the donor's kidney to the patient's -- is an important process after kidney transplantation with blood type incompatibility.

"Regarding desensitization treatment, we are talking about human leukocyte antigen A (HLA-A). If the patient has this antibody, we must remove the transplanted kidney due to a rejection reaction," he said. "In the past, if the antibody was present, transplantation was not advised. However, the rejection reaction to the antibody is so strong that some hospitals had to remove the kidney after going into the operating room for transplantation in severe cases.”

However, Yang stressed that St. Mary's Seoul Hospital could remove the HLA-A antibody, leading to a successful transplant.

"Thanks to our hospital's reputation, my team could treat a Korean living in South Africa who heard about our methods and came to Korea to receive the transplant," he said. "We conducted a successful transplant after performing the desensitization treatment to remove the antibody. Since then, the patient has come to Korea every six months from Africa for almost five years."

There are many different types of patients, but I think that patient was one of the most memorable cases, he added.

Declining number of transplant doctors

Yang also advised more young doctors to pursue transplant as their major.

"Transplant used to be called the art of medicine, so it was a fairly attractive field," he said. "However, these days, the number of medical staff dedicated to transplantation is decreasing, and I find this to be very sad."

While there are many fields of study, transplantation is a dramatic medical practice that provides a new life to patients, and the transplant is what patients want the most, he added.

Yang noted that he believes that a doctor who can do what the patient wants the most can have a very rewarding job.

"However, many doctors are trying to take an easier path," he said. "Transplant requires a lot of studies, and patient management is difficult, but it is a rewarding field, so I hope that more young teachers will become interested in transplantation."

Yang stressed that while he is an internal medicine doctor, the same phenomenon is happening in the surgical field.

"Surgeons are also picking fields that can make money, such as hemorrhoids, breasts, and thyroid glands," he said. "Transplants may not make doctors wealthy. With a bit of self-sacrifice, however, it's a fascinating field to work on. I hope more young doctors came into the field.”