Medullary Kidney Disease
Mucin-1 Kidney Disease Frequently Asked Questions
What is Mucin-1 Kidney Disease?
Mucin-1 Kidney Disease (MKD), previously known as Medullary Cystic Kidney Disease Type I (MCKD1), is a rare
disease that causes progressive kidney failure leading to the need for a kidney transplant or dialysis in most patients.
Why was it called Medullary Cystic Kidney Disease Type 1?
“Medullary” means the middle of the kidney, and
cysts are small holes. It was initially
thought that in this disease there were small holes (cysts) formed in the middle of the
kidney. However, most patients with MKD
do not have cysts in the middle of their kidney, or in other parts of their
kidney. For this reason, the name used
for this condition is incorrect.
Unfortunately, doctors have used this name for many years, and it is hard to change names.
It was called Type 1 because there
are two similar types of this disease.
It turns out that the two types of the disease are entirely
How frequent is MKD?
MKD is considered a rare disease. There are about 200 families worldwide that have been
identified with this disease.
What do the kidneys do?
The kidneys are bean-shaped organs, about the size of
a fist. They are located in the back
next to the spinal column.
Healthy kidneys filter and clean
about 200 quarts (liters) of blood every day, removing excess water, minerals,
The kidneys also produce hormones
that make red blood cells and control blood pressure. They make active Vitamin D, which the body
uses to keep your bones strong.
What happens if you have MKD?
In MKD, patients slowly lose
kidney function over time.
Kidney failure is usually
determined by a blood test, called the blood creatinine level. Creatinine is a waste product that your
muscles produce as they work. Healthy
kidneys will filter creatinine into the urine, while damaged ones will
not. Because damaged kidneys cannot
filter creatinine well, it stays in the bloodstream and the blood creatinine
Blood creatinine is part of a group
of tests that may be done as part of a routine physical or before surgery. MKD may be first identified when an elevated
creatinine is found on a routine blood test like this.
In MKD, blood creatinine levels
rise slowly over years as the kidneys become more damaged. Once the levels rise to a certain level,
usually above about 6 mg/dL (milligrams per deciliter) or about 500 mmol/L (millimoles per liter),
the patient must begin dialysis or have a kidney transplant.
At what age is dialysis or kidney transplantation needed?
In some families, all affected
persons needing kidney
replacement (this means a kidney transplant or dialysis) before 40 years of age.
In other families, age can be quite different for different persons,
with some needing dialysis in their 20’s while others are still not on dialysis
in their 60’s.
Why is a kidney transplant the only cure for MKD?
If someone has MKD, their
kidneys make an abnormal protein, and this abnormal protein gets trapped within their kidney cells. When a kidney transplant is done, the transplanted kidney is normal and does not make the abnormal
protein. Therefore the transplanted
kidney is normal and the disease will not develop in it.
How will MKD make me feel?
Many people do not even know they have a kidney disease until their
blood creatinine levels rise very high and they lose a lot of kidney function. They usually do not develop any symptoms until
the disease is very advanced. They then
become more tired than usual and just start to not feel so good. Their appetite may worsen. When kidney disease gets worse, patients like
to keep the room warmer than usual. They
often develop anemia.
My doctor told me that I have MKD.
About what age will my kidneys fail to the point I need dialysis?
There is a lot of variation as to
the age when patients will need treatment for kidney failure. In some families, patients need dialysis in
their 20’s and 30’s, while in others, they do not need it until their 60’s and
maybe even later. Even within families,
some patients go on dialysis earlier or later than their parents or
siblings. We do not know why some patients
go on dialysis earlier or later than patients in other families.
How does having MKD affect my health over the course of my life?
It is important to know that
people with kidney disease feel fine and have no health effects until they lose
half of their kidney function. At that
time, patients may start having high blood pressure and anemia. The anemia can make them feel tired, but in
general patients still feel normal.
When patients have lost about 2/3
of their kidney function they begin to feel more tired and may develop a
When 90% of kidney function is
lost, patients feel tired and have nausea and usually need a kidney transplant or dialysis.
From this you can see that most
of the kidney function has to be lost before any symptoms are noticed. Even then, the symptoms are usually quite
mild for a long period of time.
If most members of your family go on dialysis before they are 30,
you will likely feel totally normal throughout your teenage years and have no
problems. You may develop mild high blood pressure. Into your twenties, you
will slowly develop worsening kidney function and feel not quite so good. Over time, you will have worse high blood
pressure and anemia. You may need shots
to keep your blood count up. Eventually,
you will develop more fatigue and less appetite and will need a kidney transplant or dialysis.
If family members go on dialysis later in life, you will
likely feel totally normal into your 30’s and 40’s. Some individuals do not develop advanced kidney
failure even into their 60’s.
Can a urine test be used to diagnose MKD?
In many types of kidney disease there is blood and protein in the urine.
However, in MKD there is very little protein or blood in the
urine. For this reason, routine urine
tests your doctor might order are not good to diagnose MKD.
Can I prevent MKD?
Unfortunately there is no way to
Where can I get tested to find out if I have MKD?
Please contact Dr. Anthony Bleyer
at firstname.lastname@example.org or
(336)716-4513 if you are interested in genetic testing.
What can I do for my health if I have MKD?
Currently there is no known
treatment for MKD, and the only cure is a kidney transplant. However, there is still a lot that you can do
to stay healthy if you have MKD:
- Do not smoke. Smoking makes every type of
kidney disease get worse more quickly.
It also causes hardening of the arteries and lung disease. The combination of kidney disease and smoking
is not good. Thus, it is important to
stop smoking if you do smoke. Children
of affected MKD patients should be encouraged to never start smoking.
- Check blood pressure regularly. As kidney
disease worsens, blood pressure can increase.
This rise in blood pressure can lead to a higher risk of heart disease,
strokes and heart attacks. If your blood
pressure is high, you should get it treated.
You should work with your doctor to keep it under good control.
- Stay in shape and keep weight under control.
Being very overweight can make it more difficult to do the surgery for a
kidney transplant. You should watch your weight closely.
What kind of diet should I eat if I have MKD?
When kidney disease is mild you
should eat the same heart healthy diet that is recommended for the general
population. A low sodium diet with less
meat protein may be good for your health overall. It is not known if such a diet will
slow the rate of kidney disease. Before significant kidney damage has occurred, MKD patients should
have the same heart healthy diet as individuals who do not have MKD.
What about vitamins and processed sugars or an all natural diet to help
Natural diets, extreme diets, and
all natural vitamins are recommended for almost every disease. There is no evidence that any of these
treatments work for kidney disease, and especially no evidence that they are
good for MKD. The heart healthy diet that we all should eat is the diet of choice
for MKD patients without significant kidney failure.
What about MKD research?
Now that the gene for MKD has been found, a lot of research is being done on this
condition. Since there are so few
patients with this disease, every patient with the disease who takes part in
research provides helpful information.
Participating in MKD research trials is also likely to be
helpful. Please contact Dr. Anthony Bleyer at email@example.com or 336-716-4513 if you are interested.
Why is MKD research
The goal of our research is to find a cure for MKD. This is our only goal. To find a cure, we will need to study more on
how the abnormal MUC1 protein causes disease, and we need to study MUC1 production in affected
persons and compare it with persons who are unaffected.
We are also excited to be working with the Uromodulin Kidney Disease
Foundation which provides support for families, doctors and
researchers. For more information, visit: ukdcure.org
This webpage provides only general information. Please consult your physician for recommendations specific to your care. If you think you may have this disease or another type of inherited kidney disease that no one can tell you the cause, please contact Dr. Anthony Bleyer at firstname.lastname@example.org
or call 336-716-4513.