What Do the Kidneys Do?
You might never think much about some parts of your body. Your
two kidneys, each about the size of a fist, probably fall into that
category. These bean-shaped organs (as in kidney beans, not green
beans) are on both sides in the middle of your back just below your
ribcage. With about 200 quarts (189 liters) of blood pumping from
your heart through the kidneys every day, they do a big job for
such small organs.
Think of your kidneys as a sophisticated garbage collection and
disposal system. You don't use everything that gets into your
body from the food you eat, and waste products from chemical
reactions that take place in the body build up in the bloodstream.
These waste products flow to the kidneys, which sort out what
isn't needed and remove it through miniature filtering units
The kidneys maintain the delicate balance of chemicals and water
that your body needs, and they get rid of what it doesn't need.
They send the extra water and other waste as urine (pee) through
pencil-sized tubes called
-turz) to the bladder, a sack that holds the urine until you get
rid of it when you urinate.
The kidneys also help to regulate your blood pressure, red blood
cell production, and your body's calcium and other mineral
What Are the Most Common Kidney Conditions in Teens?
Sometimes, the kidneys aren't able to do their job properly.
There are many reasons why. Sometimes the blood doesn't flow to
the kidneys as well as it should. Other times the tissues of the
kidneys themselves can be damaged. And sometimes the outflow of
urine from the kidneys can become blocked and lead to kidney
When a person's kidneys stop working altogether, it's
. Someone who has kidney failure can develop a number of health
problems because the body is unable to get rid of excess water and
Other than kidney infections, the two most common kidney
conditions among teens are known by similar-sounding names:
nephritis and nephrosis.
Nephritis (pronounced: neh-
-tiss) is an inflammation of the glomeruli, the kidney's
filtering units. Nephritis may be caused by an infection, taking
certain drugs or poisonous chemicals, or by a reaction by the
body's immune system that has damaged the kidneys. When they
are inflamed (swollen and irritated), the kidneys pass protein and
red blood cells into the urine. One symptom people with nephritis
notice is that their urine can turn brownish from the blood, almost
the color of cola. Sometimes nephritis can cause pain in the side,
back, or belly, but most of the time it doesn't.
Doctors aren't always sure what causes a person to get
nephritis. Sometimes it follows a bacterial infection, such as a
streptococcus (or strep) infection like
. When nephritis comes on quickly as it often does following an
infection, doctors refer to it as acute nephritis.
Most people who get nephritis get better. However, if it's
not treated, the kidneys can sometimes be damaged or even stop
working altogether. (Occasionally, the kidneys may stop working
even if the nephritis is treated, but that's not common.)
With nephrosis (pronounced: neh-
-siss), a person's glomeruli are damaged. Instead of filtering
only wastes and excess water out of the blood to become urine, the
glomeruli allow a lot of protein to come out of the blood and into
the urine, which can lead to a condition called
. Without sufficient protein in the blood, a person may develop
-muh). Edema is swelling in areas such as the feet and legs and the
area around the eyes that is caused by excess fluid buildup in the
Someone with nephrosis may have swollen and puffy eyes,
especially when he or she wakes up. By the end of the day, the feet
may be swollen and the person's shoes might not fit. That
person will also produce much less urine - and what urine is
produced may look frothy. Other symptoms of nephrosis include
feeling weak or ill and having a loss of appetite.
Doctors don't know exactly what causes most cases of
nephrosis. It might develop as a part of another disease, such as
. Nephrosis can also happen in some types of nephritis. If
nephrosis is caused by another disease, the doctor will treat that
disease, which may reduce the symptoms of nephrosis.
What Do Doctors Do?
If you have a kidney condition, you'll probably visit a
-uh-jist), a doctor who specializes in treating kidney diseases in
kids and teens. Your doctor will ask you about any concerns and
symptoms you have, your past health, your family's health, any
medications you're taking, any allergies you may have, and
other issues. This is called the
. If a kidney condition is suspected, the doctor will want to test
your urine and blood to look for evidence of nephritis or nephrosis
and to check how well your kidneys are able to do their job
One test commonly used to detect kidney conditions is a
. Like the ultrasound pictures that pregnant women get of their
fetuses, a renal ultrasound is a picture of the kidneys that's
produced by bouncing sound waves off of them. An ultrasound is safe
and painless. The ultrasound picture shows how big the kidney is,
its shape, and whether there is anything unusual, such as blockage
of the urine flow or swelling of the kidneys.
Sometimes doctors order a test called a
, where a dye is injected into the veins and then pictures are
taken that show how blood flows through the kidneys. This tells a
doctor whether the person's urine is being formed normally. In
another test, called a
, the doctor uses a special needle to remove a tiny piece of the
kidney so that it can be examined under a microscope.
How Do Doctors Treat Nephritis and Nephrosis?
If you have nephritis that was caused by an infection, your
doctor may prescribe antibiotics. For both nephritis and nephrosis,
your doctor may give you medicine to help reduce the inflammation.
You may also be given diuretics, medicines that help your body to
get rid of extra fluid. Depending on your particular situation, you
might have to go on a special diet that limits how much salt or
other things you can eat. You also may need to take other
medications to help you recover.
Your doctor might ask you to keep a record of your temperature
every morning and night for a while, and to keep track of how much
you drink and measure how much urine you pass.
Occasionally, if medications and other treatments don't
work, the kidneys can stop working well. They may not clear enough
of the body's waste products and excess water from a
person's system. When this happens, some people may need to
start a procedure called
that uses an artificial filtering system to do the job the kidneys
aren't doing well enough.
Eventually, almost every teen who needs dialysis on a permanent
basis will receive a kidney from another person. This procedure is
. Once a person receives a transplanted kidney, he or she no longer
needs dialysis to cleanse the blood of waste products and remove
excess water - the donated, healthy kidney takes over the job.
Coping With Kidney Conditions
If you or a friend has a kidney problem, it's not likely to
affect what you do together. Nephrosis and nephritis are not
contagious (you cannot get them from someone else). Sometimes
nephrosis and nephritis can run in a person's family, although
that's not very common.
Teens who are
living with health conditions
like kidney problems will still be able to do most things,
depending on what restrictions their doctors recommend. With a
friend who has a kidney problem, the best thing you can do is what
you've always done - be a good friend. Learning about the
particular kidney condition can help, too. For example, it can help
to know that some medications can cause side effects, such as
gaining weight. If you have a friend who's in the hospital or
sick at home, visit frequently. You can do a lot to help someone
else recover just by being supportive and keeping an upbeat
Steven Dowshen, MD
Date reviewed: February 2008
Note: All information is for educational purposes only. For specific medical advice,
diagnoses, and treatment, consult your doctor.
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