Nephrotic Syndrome
Also known as: Nephrosis (NS)
What is it?
Nephrotic syndrome is the name given to a group
of medical conditions that appear related. In all
types of NS the major problem is that for some
reason the blood vessels within the kidney filter
the waste products and stops blood and protein
from getting into the urine. In NS there is lots
of protein in the urine. Because of this your
child my retain water, gain weight, and appear
swollen. In
addition to the things your doctor has told you,
this information will help you understand this
condition a little better and allow you to care
for your child more effectively. This information
is not meant to replace your regular doctor or
your nephrologist who are always willing to talk
to you and answer your questions regarding your
child’s condition.
Who gets it?
In children, there are four major causes of the
NS. The most common and the one with the best
outcome is called Minimal Change Nephrotic
Syndrome (MCNS). All told, about 80% of children
with nephrosis will have this diagnosis. Other
relatively common types of nephrosis are Focal
Segmental Glomerulosclerosis (FSGS),
Membranoproliferative Glomerulonephritis (MPGN) or
Membranous glomerulopathy (Membranous). A very
small number of children will have other
diagnoses.
What causes it?
That’s a tough question and for the most part,
we still don’t know the answer. For just a few
patients, it seems clear that NS is related to a
chronic infection or is caused when the body tries
to get rid of an invading protein (an immune
reaction). However, in most children, we still
don’t know why nephrosis develops. Whatever the
underlying cause, it looks as if the kidney’s
filtering system develops bigger holes and starts
allowing some parts of the blood (such as protein
and red blood cells) to be filtered, and therefore
lost into the urine.
What are the symptoms?
When too much protein is lost in the urine, the
amount of protein present in blood decreases.
Normally the proteins in the blood are necessary
to hold water inside the blood vessels. When blood
protein levels fall, fluid seeps out of the blood
vessels into places like the belly, legs and
around the eyes. That’s how most children with
nephrosis are recognized. They become swollen
because of the buildup of water in tissues and are
said to be edematous.
How is it diagnosed?
Over 30 years of experience have shown that
most children need only a good physical
examination and just a few laboratory tests
diagnosis NS. If your child has gained weight, is
swollen and has a large amount of protein in
his/her urine, it is likely that the NS is
present. Additional tests may have to be done to
determine the type of NS or whether there are
complications, but most often the diagnosis is
pretty clear.
What is the treatment?
For most children, treatment can be started
immediately using a medication called prednisone
(or prednisolone). This is a strong medicine with
the possibility of significant side effects but
it’s one we and your primary care doctor have had
lots of experience using. We continue to use
prednisone because it usually works well in NS. In
some patients, (mostly older or those with unusual
presentations) it may be necessary to do a kidney
biopsy before starting any medication to determine
which type of NS is present.
When prednisone is used the first episode of
nephrosis will be treated at the full dosage for
one month and then the dose will be lowered slowly
over the course of the next several months.
What should I be doing while my child is being
treated?
One of the most important things you can do is
to keep records of your child’s weight and urinary
protein. Each morning you should test your child’s
urine using a dipstik (we will explain how) and
weigh your child. Then write down that
information. Many parents find that the best way
to do this is to keep a separate calendar and
write the information in the date box. Don’t
forget to bring the list or calendar with you when
you come to our clinic.
How will I know if the medicine is working?
Most children respond to prednisone between 10
and 20 days after starting treatment and over 90%
respond before 28 days of therapy. The first
response is often a sudden increase in urination
with the loss of a large amount of (water) weight.
If your child is taking diuretics (water pills),
please call us. We may want to stop the water
pills if they are no longer needed. Don’t stop the
prednisone until told to do so. There are two
reasons for this: 1) patients who have been taking
prednisone for some time get to rely on it and
need to have the dose lowered slowly to prevent
complications and 2) stopping the prednisone too
quickly can lead to a recurrence of the NS.
What are the side effects of using prednisone?
As with any strong medicine, there are side
effects associated with the use of prednisone.
These side effects include: increase appetite with
weight gain; poor growth; high blood pressure;
loss of bone calcium; and increased possibility of
infections. While these are potentially serious
complications they are generally related to taking
high doses for a long period of time. For most
children, prednisone is still the best treatment.
Once treatment starts, when should I contact
the doctor again?
There are several reasons why we would want to
hear from you during the course of this treatment
- Retaining too much fluid (gaining too
much weight)
Sometimes children gain too much water weight,
become very uncomfortable and need some
temporary medicine to get rid of the extra fluid
until the prednisone starts working. Unless told
otherwise, if you child gains an additional 10%
of weight or if you feel that your child is very
uncomfortable, let us know. While there are
medicines (called diuretics) that can help your
child lose water, they have their own set of
complications. If possible, it would be best if
we didn’t have to use diuretics but let the
prednisone treat the NS.
- Treating for a month but your child still
has increased urinary protein.
Since most children respond within one month of
starting the full prednisone dose, if your child
doesn’t respond by one month we will want to
reconsider the diagnosis and will need to talk
with you about other tests or treatments that
may have to be performed.
- Signs of serious infection
For the most part, children with NS are quite
healthy. If their swelling isn’t too severe and
they aren’t too uncomfortable they may certainly
attend school. There are two exceptions that
need to be brought to your attention.
- Peritonitis
When the NS is active, particularly if your
child is swollen (edematous), resistance to
infection is decreased. While this isn’t a
serious problem for most children, a small
percentage develop serious infections,
particularly when their bellies are swollen.
When this happens, it is most often an abdominal
infection called peritonitis, due to a type of
bacteria called pneumococcus. These infections
need to be aggressively treated using
intravenous antibiotics. If your child develops
severe belly pain while the NS is active, please
contact us or your primary care physician
immediately.
Of course, it is better to prevent pneumococcal
infections than to have to treat them. We now
have an immunization, called Pneumovax, that
will prevent most pneumococcal infections. This
immunization should be given to all children
with NS and can be given even though your child
is receiving prednisone.
- Chickenpox (Varicella)
While chickenpox is usually a mild illness, it
can be very serious in patients who are also
taking prednisone. If your child has not already
had chickenpox or the chickenpox immunization,
this is one viral illness that you have watch
out for. Here are two situations to look out
for. 1) Tell your child’s teacher to let you
know immediately if any members of the class
develop chickenpox. 2) If your child plays with
someone who then develops chicken pox up to
three days later. In either case, please let us
or your primary care doctor know immediately.
What causes the swelling and weight gain?
- Holding on to extra salt
We have already explained that the swelling we
see in children with the NS is caused by water
seeping out of the blood vessels into other body
tissues. That explains why water shifts places
within the body, but not why the total amount of
water increases. The main reason is that in
addition to water shifting, there are other
changes that make the body want to hold on to
extra salt. Whenever you hold onto extra salt
you also hold onto water. Patients with the NS
hold onto salt very strongly. For every teaspoon
of salt that is retained, over two pounds of
water are also retained, so weight increases and
your child looks swollen.
- Prednisone treatment
Prednisone also causes salt retention as well as
a big increase in appetite. The final result is
that patients with the NS both retain salt and
water and eat more, gaining fat as well as
water.
What can I do to prevent swelling and weight
gain?
This is a very important question. The most
important thing you can do is to limit your
child’s salt intake. Without salt, they won’t
retain water and their weight won’t increase as
much. In addition, while appetite increases while
on prednisone, healthy eating habits and exercise
will limit the weight and fat gained. We strongly
recommend a low salt diet as well as healthy,
low-fat low-calorie dietary choices. It may be
necessary to visit a dietician for more complete
advise and recommendations.
Limit salt, not water
A final note about salt and water. Most children
with NS have problems holding on to too much
salt, but very few children have problems with
the way they handle water. Sure, they hold on to
extra water, but that is because they are
holding on to salt. Unless we specifically tell
you to, don’t limit your child’s fluid intake.
Limit the salt but not the water intake.
After the nephrotic syndrome is treated, will
it come back?
There is both good and bad news.
First the bad news - About 80% of
children get relapses. For some, the relapses
are infrequent and for some the relapses are so
frequent that your child will seem to be on
prednisone most or all of the time. Relapses
will usually be treated with shorter courses of
prednisone. When the relapses happen very
frequently or when other complications occur, we
may want to discuss other treatment options with
you. All strong medicines have some side effects
and in each case the parents (and the patient),
along with the doctor, will have to decide on
the best approach to take.
What’s the good news?
For the majority of children with NS, this
condition will go away sometime before or during
puberty. We can’t tell whether your child will
be in this group, but the odds are strongly in
your favor.
About the diet
Remember, since your child will probably have
several episodes of NS before outgrowing it as a
teenager, it is important to be consistent. You
can’t expect him/her to understand why they can
eat lots of salty, fatty foods one day, only to
have to restrict them the next, or to eat a diet
that’s different than the rest of the family.
It’s probably better to have your whole family
improve their dietary habits as well. We would
all benefit from diets that are lower in salt
and saturated fats.
What causes a relapse?
Just as we don’t know why children develop
nephrosis, we don’t really understand why the NS
returns. Experience, however has allowed us to
make some general comments.
- Fever or infection
We know that fever or infection will increase
urinary protein levels in all of us. Children
with nephrosis are just as likely to have other
illnesses as children without nephrosis and
their urinary protein levels may also increase.
Unfortunately, for some of these children, once
their urine protein levels begin to rise, they
continue to go up even when the infection is
over. In these children we have to restart or
increase the amount of prednisone to get them
back into remission. We will often try and hold
off as long as we can before restarting
prednisone. You can help by remembering how your
child responds to a fever; by remembering his
regular weight (so we can tell if he has gained
weight) and by checking the morning urine for
protein at the first sign of illness.
- Lowering the dose of prednisone
Each child is different and may respond in
different ways as we lower the prednisone. We
try to lower the dosage of prednisone as fast as
we can to minimize side effects while going
slowly enough to prevent a relapse. You will
become very knowledgeable about your own child’s
response, and we will ask for your help and
memory as we work with you to treat your child.
- Allergies
For just a few children, the NS can be triggered
by an allergy. This is not common but has been
noted in the literature.
How can I tell if my child is having a
relapse?
The first time your child developed nephrosis
no one was expecting it and s/he was probably
swollen. Since we know that most children will get
further episodes of nephrosis we ask you to be on
guard so that we can detect the beginnings of a
relapse before the swelling returns. There is an
orderly sequence of events that happens before
swelling is visible. First the kidney starts to
lose too much protein. This can by measured in the
urine by using a dipstik. Even without using the
dipstik, parents and children will often say that
the urine is unusually foamy. This foam is caused
by the extra protein in the urine giving it a
“head.” If the loss of protein continues, the
blood protein levels fall and your child will
start holding onto water, urinating less often and
gaining weight. Finally, the increase in body
fluid will get to the point where you can see
swelling (also called edema). We would like to
restart the medicine sometime between when the
urine protein increases and before your child
develops edema
So What do I look for
- Check the urine for protein
- Is the urine foamy?
- Is your child urinating less often?
- Is your child’s weight increasing rapidly?
- Does your child look “puffy?”
What should I do if the nephrotic syndrome
returns?
As we have noted several times, NS is likely to
return, occasionally in some children, often in
others. You can help by being a good record
keeper; remembering how your child responds to
infections and to different treatments. Early on,
we will be asking you to check your child’s urine
each morning and record the result. If your child
has gone a considerable amount of time without a
relapse, it should be OK to test the urine less
often than once/day, perhaps once or twice/week.
You will probably want to check more frequently
again during viral infections. Of course, it is
still important to keep a record of each urine
test for your child’s doctor to refer to. The same
is true about your child’s weight. When you call
the doctor you will be asked “has your child
gained/lost weight?” This is one of the main ways
we try and tell whether there is a relapse and
whether we can wait or need to restart treatment.
One morning/week weigh your child and record the
weight.
Generally, we ask parents to call if their
child develops 3+ or 4+ protein in the urine for 3
or 4 days. Don’t worry, it takes time for the
blood proteins to fall. If we catch it this early,
your child shouldn’t be gaining weight as yet.
Also, call if your child gains a significant
amount of weight from one week to the next.
Certainly, your child’s weight may go up and down
somewhat depending on last night’s dinner etc. A
good general rule is that if your child gains 3-4
pounds or 10% of his/her body weight in a week,
you should check with your doctor.
What if the prednisone doesn’t cure the
nephrotic syndrome?
Frequent Relapses/Steroid Dependence
While prednisone works for a very high
percentage of children with NS, some relapse so
often that the children are almost always taking
prednisone. They can begin to develop some of
the complications noted above. If that is the
case for your child, we will continue
re-evaluating him/her to see if we should switch
to or add another medicine. All strong medicines
have their own risks and benefits and we will,
of course, discuss this with you before coming
to a decision.
Non-Responders
A small percentage of children don’t respond to
prednisone, either from the first episode or
beginning at some later time. If your child
becomes unresponsive to prednisone s/he will
require a kidney biopsy so that we can determine
what kind of nephrosis is present and what the
best to treatment would be. This is a very safe
procedure that is only required in 10-15% of our
patients. Of course, if we feel that your child
will require a kidney biopsy they will discuss
it with you in full detail before any decision
is required
Will my child grow up and be a healthy normal
adult?
We realize that taking care of a child with
nephrosis is aggravating and annoying but, as
we’ve said before, it generally goes away sometime
during childhood or adolescence. Kidney function
remains normal for children with the most common
kind of nephrosis (Minimal Change Nephrotic
Syndrome)and the do not develop kidney failure. We
hope to work with you and your primary care
physician to help you and your child deal with the
NS in a safe and reasonable manner. We are always
available to answer your questions and look
forward to interacting with you as we work
together to keep your child healthy and happy.
This information has been designed as a comprehensive and quick reference
guide written by our health care reviewers. The health information written
by our authors is intended to be a supplement to the care provided by your
physician. It is not intended nor implied to be a substitute for
professional medical advice.
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