When you're hungry, your stomach lets out a growl or two.
When you run around, your heart lets you know it's really
working by boom, boom, booming! But some important body parts are
quiet as a whisper. Psst - we're talking about your
What Are the Kidneys?
Your kidneys are tucked under your lower ribs on either side of
your spine. Each one is about the size of your fist and shaped like
a bean. Most people have two kidneys, but they work so effectively
that a person can be happy and healthy with only one.
Think that's cool? Check out their job: each day your
kidneys act like high-powered filters for about 200 quarts (189
liters) of fluid in your flowing blood. That's enough fluid to
fill 100 of those big soda bottles that hold 2 liters each!
Your kidneys remove waste and excess fluid that naturally builds
up in your blood after your body breaks down food. The kidneys
collect that stuff and send it on to the bladder as
(pee), so you can get rid of it when you go to the bathroom.
Besides taking out your body's "trash," your
kidneys help balance your body's vitamin and mineral levels so
your other organs and bones can do their best work. They help in
the production of red blood cells and produce a form of vitamin D,
which promotes healthy bones. If that's not enough, they help
keep your blood pressure at a healthy level.
Kinds of Kidney Diseases
Like any complicated machine, not all kidneys work perfectly.
When someone's kidneys have problems for a long time, doctors
call it a chronic kidney disease. Children's kidney problems
are either congenital (say: kun-
-uh-tul) or acquired (say: uh-
The difference is that a congenital problem exists from the day
someone is born. An acquired kidney problem develops over time,
often due to an injury, kidney infection, or other illness. Many
congenital kidney problems are hereditary, which means they're
passed down through a person's genes. Acquired kidney problems
are not hereditary.
Two of the most common kidney problems are congenital. One of
them is obstructive uropathy (say:
-pah-thee). This means something is blocking urine flow and keeping
the kidneys from doing their waste-removing job properly.
Another congenital problem is renal dysplasia (say:
-zhuh). A person with renal dysplasia was born with kidneys that
are smaller than they should be or that didn't form correctly.
This makes it difficult for the kidneys to work the way they
How Are Kidney Diseases Diagnosed?
Kidney problems are often not noticed at an early stage. As the
illness progresses, someone with a kidney disease may feel tired,
nauseated, itchy, or dizzy. The person also might have puffy eyes,
ankles, or feet because the body has trouble getting rid of extra
fluid. Someone who has these problems needs to go to the
At a doctor visit, the doctor would examine the person and ask
questions about past and current health problems. Doctors can
use many special tests to find out if someone's kidneys
are working properly. Blood pressure can be measured - if it's
high, it may indicate a kidney problem. Because the kidneys produce
urine, the doctor can check a person's pee for blood or
protein. Normal urine usually doesn't contain much of either
The doctor also might take a little bit of the person's
blood to check the amount of something called creatinine (say:
-at-in-een), a natural waste product that muscles release into the
blood. The level of creatinine can go up too high if the kidneys
aren't working well.
Some doctors check for growths or blockages by using machines
that take special pictures, like X-rays, ultrasound scans, or CAT
scans. To pinpoint the problem, a doctor may also do a biopsy (say:
-see). In this test, the doctor takes out a tiny piece of kidney
tissue with a needle and looks at it under a microscope. Doctors
and nurses will give medicine called anesthesia to keep the person
comfortable during the biopsy.
How Do Doctors Treat Kidney Problems?
The treatment for chronic kidney problems depends on how well
the kidneys are working. It may include vitamins, minerals, and
medications to help with growth and to prevent bone disease.
Sometimes unhealthy kidneys have problems producing a hormone that
helps make red blood cells, the cells that carry oxygen to your
When a person doesn't have enough red blood cells,
, which can make someone feel worn out. If this is a problem, the
doctor may prescribe blood transfusions or medicine that helps the
body make red blood cells.
Kids with kidney problems are more likely to get high blood
pressure, which can be harmful if it isn't controlled. In those
cases, a kid may have to take blood pressure medicine.
For kidneys that need even more help, doctors might suggest
-al-uh-sis), a process that cleans the blood artificially. A kidney
transplant is another possibility. In this operation, doctors
replace a kidney that doesn't work with a healthy kidney
donated by another person.
What's Life Like for Kids With Kidney Problems?
Kids who have kidney problems are just like other kids, but they
may have to take special medicine or go to the hospital for
treatments, such as dialysis. They also will need to talk with
their doctors about participating in sports, but often they can
join in the fun. Some kids may need to avoid contact sports, such
as football, soccer, or basketball.
Kids with kidney illnesses also may need to talk with a doctor
or dietitian about the foods they eat. Some kids won't have to
follow any special diet, but others may need to avoid salty foods
and limit the amount of fluid they drink. Potassium and protein
also may be a concern for someone with a kidney disorder.
It's no fun to be sick, no matter the cause. But the good
news for kids with kidney problems is that they can take steps to
stay healthier and feel better, with a little help from their
families and doctors.
Laszlo Hopp, MD
Date reviewed: March 2009
Note: All information is for educational purposes only. For specific medical advice,
diagnoses, and treatment, consult your doctor.
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