Chronic kidney disease
Overview
Chronic kidney disease, also called chronic
kidney failure, describes the gradual loss
of kidney function.
Your kidneys filter wastes and excess fluids
from your blood, which are then excreted in
your urine.
When chronic kidney disease reaches an advanced
stage, dangerous levels of fluid, electrolytes
and wastes can build up in your body.
In the early stages of chronic kidney disease,
you may have few signs or symptoms.
Chronic kidney disease may not become apparent
until your kidney function is significantly
impaired.
Treatment for chronic kidney disease focuses
on slowing the progression of the kidney damage,
usually by controlling the underlying cause.
Chronic kidney disease can progress to end-stage
kidney failure, which is fatal without artificial
filtering (dialysis) or a kidney transplant.
Symptoms
Signs and symptoms of chronic kidney disease
develop over time if kidney damage progresses
slowly.
Signs and symptoms of kidney disease may include:
Nausea
Vomiting
Loss of appetite
Fatigue and weakness
Sleep problems
Changes in how much you urinate
Decreased mental sharpness
Muscle twitches and cramps
Swelling of feet and ankles
Persistent itching
Chest pain, if fluid builds up around the
lining of the heart
Shortness of breath, if fluid builds up in
the lungs
High blood pressure (hypertension) that's
difficult to control
Signs and symptoms of kidney disease are often
nonspecific, meaning they can also be caused
by other illnesses.
Because your kidneys are highly adaptable
and able to compensate for lost function,
signs and symptoms may not appear until irreversible
damage has occurred.
Diagnosis
As a first step toward diagnosis of kidney
disease, your doctor discusses your personal
and family history with you.
Among other things, your doctor might ask
questions about whether you've been diagnosed
with high blood pressure, if you've taken
a medication that might affect kidney function,
if you've noticed changes in your urinary
habits, and whether you have any family members
who have kidney disease.
Next, your doctor performs a physical exam,
also checking for signs of problems with your
heart or blood vessels, and conducts a neurological
exam.
For kidney disease diagnosis, you may also
need certain tests and procedures, such as:
Blood tests.
Kidney function tests look for the level of
waste products, such as creatinine and urea,
in your blood.
Urine tests.
Analyzing a sample of your urine may reveal
abnormalities that point to chronic kidney
failure and help identify the cause of chronic
kidney disease.
Imaging tests.
Your doctor may use ultrasound to assess your
kidneys' structure and size.
Other imaging tests may be used in some cases.
Removing a sample of kidney tissue for testing.
Your doctor may recommend a kidney biopsy
to remove a sample of kidney tissue.
Kidney biopsy is often done with local anesthesia
using a long, thin needle that's inserted
through your skin and into your kidney.
The biopsy sample is sent to a lab for testing
to help determine what's causing your kidney
problem.
Treatment
Depending on the underlying cause, some types
of kidney disease can be treated.
Often, though, chronic kidney disease has
no cure.
Treatment usually consists of measures to
help control signs and symptoms, reduce complications,
and slow progression of the disease.
If your kidneys become severely damaged, you
may need treatment for end-stage kidney disease.
Treating the cause
Your doctor will work to slow or control the
cause of your kidney disease.
Treatment options vary, depending on the cause.
But kidney damage can continue to worsen even
when an underlying condition, such as high
blood pressure, has been controlled.
Treating complications
Kidney disease complications can be controlled
to make you more comfortable.
Treatments may include:
High blood pressure medications.
People with kidney disease may experience
worsening high blood pressure.
Your doctor may recommend medications to lower
your blood pressure — commonly angiotensin-converting
enzyme (ACE) inhibitors or angiotensin II
receptor blockers — and to preserve kidney
function.
High blood pressure medications can initially
decrease kidney function and change electrolyte
levels, so you may need frequent blood tests
to monitor your condition.
Your doctor will likely also recommend a water
pill (diuretic) and a low-salt diet.
Medications to lower cholesterol levels.
Your doctor may recommend medications called
statins to lower your cholesterol.
People with chronic kidney disease often experience
high levels of bad cholesterol, which can
increase the risk of heart disease.
Medications to treat anemia.
In certain situations, your doctor may recommend
supplements of the hormone erythropoietin
(uh-rith-roe-POI-uh-tin), sometimes with added
iron.
Erythropoietin supplements aid in production
of more red blood cells, which may relieve
fatigue and weakness associated with anemia.
Medications to relieve swelling.
People with chronic kidney disease may retain
fluids.
This can lead to swelling in the legs, as
well as high blood pressure.
Medications called diuretics can help maintain
the balance of fluids in your body.
Medications to protect your bones.
Your doctor may prescribe calcium and vitamin
D supplements to prevent weak bones and lower
your risk of fracture.
You may also take medication known as a phosphate
binder to lower the amount of phosphate in
your blood, and protect your blood vessels
from damage by calcium deposits (calcification).
A lower protein diet to minimize waste products
in your blood.
As your body processes protein from foods,
it creates waste products that your kidneys
must filter from your blood.
To reduce the amount of work your kidneys
must do, your doctor may recommend eating
less protein.
Your doctor may also ask you to meet with
a dietitian who can suggest ways to lower
your protein intake while still eating a healthy
diet.
Your doctor may recommend follow-up testing
at regular intervals to see whether your kidney
disease remains stable or progresses.
Treatment for end-stage kidney disease
If your kidneys can't keep up with waste and
fluid clearance on their own and you develop
complete or near-complete kidney failure,
you have end-stage kidney disease.
At that point, you need dialysis or a kidney
transplant.
Dialysis.
Dialysis artificially removes waste products
and extra fluid from your blood when your
kidneys can no longer do this.
In hemodialysis, a machine filters waste and
excess fluids from your blood.
In peritoneal dialysis, a thin tube (catheter)
inserted into your abdomen fills your abdominal
cavity with a dialysis solution that absorbs
waste and excess fluids.
After a period of time, the dialysis solution
drains from your body, carrying the waste
with it.
Kidney transplant.
A kidney transplant involves surgically placing
a healthy kidney from a donor into your body.
Transplanted kidneys can come from deceased
or living donors.
You'll need to take medications for the rest
of your life to keep your body from rejecting
the new organ.
You don't need to be on dialysis to have a
kidney transplant.
For some who choose not to have dialysis or
a kidney transplant, a third option is to
treat kidney failure with conservative measures.
However, once you have complete kidney failure,
your life expectancy generally would be only
a few months.
Potential future treatments
Regenerative medicine holds the potential
to fully heal damaged tissues and organs,
offering solutions and hope for people who
have conditions that today are beyond repair.
Regenerative medicine approaches include:
Boosting the body's natural ability to heal
itself
Using healthy cells, tissues or organs from
a living or deceased donor to replace damaged
ones
Delivering specific types of cells or cell
products to diseased tissues or organs to
restore tissue and organ function
For people with chronic kidney disease, regenerative
medicine approaches may be developed in the
future to help slow progression of the disease.
Lifestyle and home remedies
As part of your treatment for chronic kidney
disease, your doctor may recommend a special
diet to help support your kidneys and limit
the work they must do.
Ask your doctor for a referral to a dietitian
who can analyze your current diet and suggest
ways to make your diet easier on your kidneys.
Depending on your situation, kidney function
and overall health, your dietitian may recommend
that you:
Avoid products with added salt.
Lower the amount of sodium you eat each day
by avoiding products with added salt, including
many convenience foods, such as frozen dinners,
canned soups and fast foods.
Other foods with added salt include salty
snack foods, canned vegetables, and processed
meats and cheeses.
Choose lower potassium foods.
Your dietitian may recommend that you choose
lower potassium foods at each meal.
High-potassium foods include bananas, oranges,
potatoes, spinach and tomatoes.
Examples of low-potassium foods include apples,
cabbage, carrots, green beans, grapes and
strawberries.
Be aware that many salt substitutes contain
potassium, so you generally should avoid them
if you have kidney failure.
Limit the amount of protein you eat.
Your dietitian will estimate the appropriate
number of grams of protein you need each day
and make recommendations based on that amount.
High-protein foods include lean meats, eggs,
milk, cheese and beans.
Low-protein foods include vegetables, fruits,
breads and cereals.
