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School of Medicine
Featuring Karl Womer, M.D., Assistant Professor of Medicine, Nephrology
Describe what you do.
I’m Doctor Karl Womer, Assistant Professor of Medicine at Johns Hopkins. My role is to perform the medical evaluations of potential kidney donors. These evaluations include an extensive review of the medical history and complete physical exam, including review of pertinent labs and imaging studies, and an extensive counseling session regarding the potential medical risks of donation.
What makes someone a good candidate to donate a kidney?
To be a kidney donor, one must have no evidence of kidney disease, but also not have any evidence of major medical conditions that would unduly increase the risk for kidney disease in the future.
What are some of the reasons why someone might donate a kidney?
The most common reason for donation is due to emotional ties, such as between spouses and other family members. However, increasingly we are finding donors who are interested in donating in a non-directed fashion. In these donations, they donate to people they do not personally know. The motivations of these individuals is best summed up by one of my previous donors who said that his life would not be complete if he died with two kidneys and was not able to donate one to someone to help them out.
What are the misconceptions about kidney donation?
The biggest misconception that I think we have in the donation process is that there needs to be a perfect match. Certainly the outcomes are improved when the donor and recipient are perfectly matched, however we know now that the survival on dialysis is greatly decreased compared to transplantation, so it is really important to have a transplant as soon as possible and with any degree of matching it’s better to have a transplant than not.
What are the medical conditions that may prevent someone from donating a kidney, like diabetes?
First and foremost, we want to ensure that a donor is healthy enough to survive the surgery with no major complications; however we are also concerned about their future risk of kidney disease. Diabetes is a major medical problem in the United States and worldwide, and 30-40% of diabetics will develop some form of kidney disease. Part of my job is to ensure that a potential donor does not have diabetes and that their risk for developing diabetes in their lifetime is acceptably low.
Is hypertension a factor in kidney donation?
We know that hypertension can contribute to kidney disease, however we have found that certain individuals over 50 years of age can safely donate a kidney with hypertension, as long as their hypertension is well controlled and they have no other major medical comorbidities.
Is obesity a factor in whether or not someone is considered for kidney donation?
Obesity is a major epidemic in the United States nowadays and research has not been done to determine the long term consequences of obesity on kidney disease. For our donors, we recommend that they limit caloric intake and perform regular exercise to keep their body weight in the normal range.
What do you do to manage the health of the donor before and after donation surgery?
First and foremost, we want to ensure that the donor is healthy enough to undergo donation surgery without any major medical or surgical complications. However, there is also concern for the long term health of the individual and our donors are followed on a regular basis by a transplant coordinator who will review their lab work at periodic intervals and make recommendations as needed to keep them in health.
Are there any short term effects from donating a kidney?
There are potential medical complications following donation. For instance, studies have shown that blood pressure can rise a bit after the donation process. There are more worrisome long term medical complications, including the need for dialysis in the future. We hope to minimize this through our evaluation process, but we know there will be some donors who, unfortunately, do lose their kidney function and require dialysis. Several recent studies, however, have shown that donors tend to do as well or better than the general population in regard to long term medical complications.
If someone donates a kidney and later in life that kidney fails, do they receive priority for a transplant themselves?
Unfortunately, some donors have lost their kidney function and require dialysis several years after donation. There is a priority system in place so that donors receive extra points for deceased donor kidney transplant when they are on the waiting list.
Why should someone considering donating a kidney choose Johns Hopkins?
I think the most important part of Johns Hopkins transplantation is the teamwork. All members of the team across the whole spectrum work extremely hard and feed off each other to do the best job they can in taking care of our patients.