JHU Docs Do Kidney Swap

By Sarah Williams

March 12, 2004

On Feb. 29, the amazingly warm Sunday when most Hopkins students were outside enjoying the sunshine, surgeons at The Johns Hopkins Comprehensive Transplant Center were doing something much different.

By the end of the day, they had completed the world's first "triple swap" kidney transplant using a new technique, called plasmapheresis.

Plasmapheresis is a way of removing antibodies from the patient's blood so that they are able to accept an organ from anyone, even someone who doesn't have a perfect match in terms of blood type.

According to the National Kidney Foundation (NKF), kidneys are two organs which are located just below the ribcage, with one situated on each side of the spine. They are about the size of a fist and look like a kidney bean.

Kidneys have a variety of functions in keeping the body working correctly. Their primary job is to filter blood as is circulates through the body.

Each organ in the body produces wastes as it functions throughout the day. This waste enters the blood. However, something has to clean the blood so that these wastes don't build up over time.

This is where the kidneys come in. An artery from the heart leads directly to the kidneys. Many tiny blood filters collect waste and only allow clean blood to return to the blood stream. The wastes which have been collected from the blood are then sent to the bladder where they are stored as urine.

The kidneys' other jobs are also related to keeping circulating blood healthy.

For example, they control the production of red blood cells, one of the most important components in your blood.

They also regulate the amounts of certain nutrients which are present in your body, as well as control blood pressure.

According to the NKF, every 24 hours about 200 quarts of blood are filtered through the body. About two quarts of this are excreted from the body in the form of urine. The other 198 quarts are newly cleaned blood, which can continue circulating throughout the body.

What happens, however, when the kidneys stop working perfectly?

There are more than 20 million Americans currently diagnosed with chronic kidney disease, which the NKF calls one of the most costly illnesses in the country.

This is, in a large part, due to the fact that more than 378,000 of those with chronic kidney disease rely on an artificial kidney machine to stay alive.

In addition to those who need artificial kidney machines, there are an additional 50,000 patients who are waiting for kidney transplants. Only 14,000 of them, however, are expected to receive a transplant this year, because of the overwhelming shortage of organ donors.

This is where the Hopkins team comes in. The kidney transplant programs at Johns Hopkins have been developing multiple ways to increase the number of people who can get transplants.

This is the first time that two of these methods have been combined, to allow three people to simultaneously receive transplants.

Their first method is one of multiple kidney exchanges. The premise behind it is that there often may be a family member who is willing to donate an organ to a loved one.

However, if their blood type doesn't match exactly, this transplant is not realistic.

For a transplant to be successful, the blood type of the donor and the acceptor must be the same.

One of the body's mechanisms against disease is to reject blood which does not match its own. This is regulated by having multiple blood types among the human population.

In order to solve this problem, the Hopkins center arranged a program in which pairs of people whose blood types do not correspond can be matching with another pair and switch kidneys. This way, both donors still give their organs and both recipients still receive a functioning organ.

Since last summer, this program has been even further expanded to allow three pairs to switch organs. This is the so-called "triple swap" kidney exchange.

The second method which Hopkins has been working on in order to increase the availability of transplants is a technique called plasmapheresis.

In this method, doctors filter the blood of the recipient so that it is more likely to accept a donor organ. They remove the antibodies which allow blood to distinguish different blood types.

They also allow any other proteins that the recipient may have been exposed to which would not match with the donor's blood.

This method enables someone to donate an organ to someone who has a different blood type from themselves.

By combining these two methods, Hopkins doctors have made it so that virtually anyone can give someone else a kidney, regardless of their blood type or how compatible they may have been in the past.

This was the seventh "triple swap" kidney exchange, but it was the first time that plasmapheresis had been used at the same time.

All six people involved in the swap were from the United States, marking the second time that a "triple swap" kidney exchange has been between six Americans.

The lead surgeon on this case was Dr. Robert A. Montgomery, M.D., Ph.D., who also is the director of the incompatible kidney transplant programs at Johns Hopkins.

Considering the number of people waiting for kidneys, these advances are incredibly timely and important to the medical community.

According to the NKF, more than 12,000 kidney transplants were performed in 2002.

Perhaps with the advances made at Hopkins, this number will be able to rise dramatically in the coming years.

Those waiting for an organ and their loved ones, certainly hope so.

This article posted April 2, 2004.

JHU Docs Do Kidney Swap

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