Other Conditions and Diseases
Chronic Kidney Disease (CKD)
Topic written or edited by:
Samuel S. Blumenthal, MD
Barbara A. Bresnahan, MD
Jack G. Kleinman, MD
Walter F. Piering, MD, FACP
About Chronic Kidney Disease
Your Glomerular Filtration Rate (GFR) is the best indicator of how well your kidneys are working. In 2002, the National Kidney Foundation published treatment guidelines that identified five stages of Chronic Kidney Disease (CKD) based on declining GFR measurements. The guidelines recommend different actions based on the stage of kidney disease.
- Increased risk of CKD. A GFR of 90 or above is considered normal. Even with a normal GFR, you may be at increased risk for developing CKD if you have diabetes, high blood pressure, or a family history of kidney disease. The risk increases with age: People over 65 are more than twice as likely to develop CKD as people between the ages of 45 and 65. African Americans also have a higher risk of developing CKD.
- Stage 1: Kidney damage with normal GFR (90 or above). Kidney damage may be detected before the GFR begins to decline. In this first stage of kidney disease, the goals of treatment are to slow the progression of CKD and reduce the risk of heart and blood vessel disease.
- Stage 2: Kidney damage with mild decrease in GFR (60 to 89). When kidney function starts to decline, your health care provider will estimate the progression of your CKD and continue treatment to reduce the risk of other health problems.
- Stage 3: Moderate decrease in GFR (30 to 59). When CKD has advanced to this stage, anemia and bone problems become more common. Work with your health care provider to prevent or treat these complications.
- Stage 4: Severe reduction in GFR (15 to 29). Continue following the treatment for complications of CKD and learn as much as you can about the treatments for kidney failure. Each treatment requires preparation. If you choose hemodialysis, you will need to have a procedure to make a vein in your arm larger and stronger for repeated needle insertions. For peritoneal dialysis, you will need to have a catheter placed in your abdomen. Or you may want to ask family or friends to consider donating a kidney for transplantation.
- Stage 5: Kidney failure (GFR less than 15). When the kidneys do not work well enough to maintain life, you will need dialysis or a kidney transplant.
- Physical symptoms: Usually few or no physical symptoms that you can feel (other than those you may experience if you have a lot of protein in your urine).
- Blood work: Blood work results will show abnormalities - mainly a slightly elevated serum creatinine.
- Urinalysis: Urine will show abnormalities. Urine can be checked by dipstick in the doctor's office (as an initial check) and followed up with a more complete urinalysis. The main urine abnormality that will suggest a kidney disease is the presence of protein and/or blood. Either will usually trigger further investigation. Importantly, blood and/or protein in the urine does not say anything about actual kidney function.
- Treatment: Treatment may involve some mild dietary changes (a lower sodium diet is often recommended) and a blood pressure medication may be prescribed (usually of the ACE inhibitor class or the angiotensin II receptor blocker class) even if blood pressure is not really elevated much.
- Blood pressure: Some people start having high blood pressure even in early chronic kidney disease.
- Anemia: Anemia may rarely occur at this stage. In this case, it is most often caused by having a lot of protein in the urine rather than actual chronic kidney disease.
- Physical symptoms: You may still feel completely normal at this stage, or you may begin to experience one or more of the following symptoms:
- Tiredness or fatigue
- Puffiness or swelling (obvious in the hands or feet and ankles, but the puffiness will often first be seen around the eyes).
- Back pain. Usually felt as a dull ache anywhere in the mid-to-lower portion of the back, on one side or the other - this is sometimes referred to as flank pain, or loin pain.
- Changes in appetite or eating pattern. Foods may start tasting "funny."
- Urine: Changes in urination (amount, color, frequency). Urine may in fact look exceptionally clear at this point. This is because little is actually being filtered by your kidneys. Some patients that previously had blood or protein in the urine may see these findings improve.
- Blood pressure: High blood pressure (also referred to as hypertension) is common.
- Digestion: Poor digestion (varying degrees of gastroparesis, which means that digestion is slowed).
Diet: Dietary changes may be ordered (Kidney diet: low potassium, low phosphorus, low sodium, and higher calorie). Occasionally a lower protein diet may be advised.
- High blood pressure medications: It is common to need more than one medication at this stage (often 3 or more).
- Other drugs/supplements may be prescribed if needed. Including vitamin D and kidney vitamins (not a regular multi-vitamin, as these contain too much vitamin A for the typical advanced kidney disease patient).
- High Phosphorus levels: You may be asked to begin taking a calcium supplement with meals as a phosphorus binder. These medications help keep phosphorus levels in the normal range which helps protect your blood vessels from harmful build up.
The terms end-stage renal failure and end-stage renal disease are used interchangeably, and the abbreviation ESRD is commonly used. Typically, patients will have kidney function in the area of 5-10% or so. These are the common symptoms you may experience at this stage (and some people may start experiencing some of these earlier):
- Anemia (may begin earlier than this)
- Easy bleeding and bruising
- Fatigue and drowsy feeling (more than normal or usual for you)
- Mental symptoms such as lowered mental alertness, trouble concentrating, confusion, seizures
- Nausea, vomiting, and generally less desire to eat
- Muscle cramps, muscle twitching
- Increased night-time urination
- Numb sensation in the extremities
- Itchy skin, itchy eyes
- Skin color changes (grayish complexion, sometimes yellowish-brownish tone)
- Swelling and puffiness (more than you had while in advanced kidney disease, and most likely in the feet and/or ankles)
- Difficulty breathing (due to fluid in the lungs, anemia)
- High blood pressure
- Decreased sexual interest
- Changes in menstrual cycle (and difficulty getting pregnant)
- Decreased urine output (however, you should be aware that some people with ESRD will continue to get rid of water as urine, but not wastes - therefore, the urine may be very clear and normal-looking, and some may have increased urine output rather than decreased).
- Poor digestion (varying degrees of gastroparesis)
The exact time that dialysis starts varies slightly depending on multiple factors. Consult your nephrologist.
- Kidney transplant
20-30% kidney function
Refer for Renal Replacement Therapy classes, also referred to as pre-dialysis classes. This is where patients are introduced to the concept of the kidney diet and have the renal replacement options explained to them, i.e. hemodialysis, peritoneal dialysis, and kidney transplantation. This allows patients to make an informed choice of treatment method when the time comes. In some areas, handouts may be used in place of actual classes. Around this time, you will probably also be told to start taking calcium with meals as a phosphorus binder, if you haven't already (don't do this on your own).
15-20% kidney function (or thereabouts)
Sometime during this timeframe your nephrologist will want you to choose a dialysis method so that the dialysis access to your body can be arranged. This is also the time when patients can be evaluated for kidney transplantation. Your nephrologist may also ask if you have any potential kidney donors.
Kidney transplant waiting list
If you do not plan to have a pre-emptive kidney transplant, it's still a good idea to go through your evaluation as a potential kidney transplant recipient before you start dialysis. That way, you will be on the waiting list and able to receive a kidney if one should come along soon after you start dialysis. Otherwise, you could miss out if your evaluation is only started once you are on dialysis.
Some important information about getting listed:
Getting on the waiting list does not happen automatically. Make sure your nephrologist knows you want a transplant, and that however it happens, you do actually get referred to a kidney transplant center. Once this happens, you will need to go through a potential kidney transplant recipient evaluation, which usually includes a complete medical evaluation, medical tests (such as various heart tests), a psychological and/or social worker evaluation, interviews with a transplant nephrologist and a transplant surgeon. This evaluation can easily take a number of months. It usually can be completed before you actually reach the point of needing dialysis.
In Canada, you can be evaluated while you are pre-dialysis, but the exact rules which govern may vary from Province to Province, and from region to region within each province. Using the Province of Ontario as an example, no matter when you complete the evaluation, before or after having started dialysis, your time on the waiting list begins the exact date that you start dialysis, not before (it is retroactive if you completed the evaluation after having started dialysis). If you have a potential live donor, you will be put on hold from the waiting list while that person is being evaluated. This is done because a kidney from a live donor is considered to be superior to one from the waiting list. The reasoning behind starting everyone's time on the waiting list as of the date of first dialysis is that evidence has shown that the longer a person is on dialysis, the more overall health declines. Therefore, it is believed to be more fair to everyone that time on the list begins on the date of first dialysis. Some people may have completed their evaluation before dialysis, some after. Some may have been on hold one or more times because of other illnesses, etc., but nobody is penalized for having had delays in their potential recipient evaluation or for having had other illnesses during the course of dialysis.
In the United States, you can usually be evaluated as a potential kidney transplant recipient within the 2-3 year period before you would be expected to start dialysis. If you have done so, credit for waiting time on the waiting list begins when you have reached 20% kidney function (more precisely, a GFR of less than 20, as per a rule change implemented by UNOS in 1998). Since dialysis is typically started when GFR is about 10%, it is therefore possible to obtain a cadaveric kidney transplant before having actually started dialysis.
15 to 10% kidney function (more or less). It will vary based on a patient's symptoms, but this is the timeframe when dialysis is started. A person who is diabetic will often be started at 15% kidney function, while most IgAN patients would start at about 10%. It's common practice these days to start dialysis in a planned manner, rather than waiting until it becomes an emergency situation (thankfully!). Most people will either start dialysis or have the pre-emptive kidney transplant done when or slightly before they reach 10% kidney function. Some people may reach 10% without experiencing any major symptoms, but, generally, dialysis will be started at this point, if not slightly before, in a planned fashion, even if the patient doesn't feel any significant symptoms. Since there is still about 10% kidney function at this point, it may be possible to continue quite some time without dialysis, but starting dialysis early increases chances of an easier transition, and it allows time to initiate dialysis in a way that minimizes stress on the body.
Contrary to popular misconception, there is no advantage to being able to delay dialysis even if no symptoms of renal failure are felt once kidney function (glomerular filtration rate) reaches about 10%, and there may in fact be significant disadvantages for the patient in terms of mortality and morbidity.
Walter F. Piering, MD, FACP
Kevin R. Regner, MD, MS, FASN
Glomerulonephritis is the term used to describe a group of diseases that damage the part of the kidney that filters blood. When the kidney is damaged, it cannot get rid of wastes and extra fluid in the body. If the illness continues, the kidneys may stop working completely. Some other terms you may hear used are nephritis and nephrotic syndrome.
Blood enters the kidneys through arteries that branch inside the kidneys into tiny clusters of looping blood vessels. Each cluster is called a glomerulus, which comes from the Greek word meaning filter. The plural form of the word is glomeruli. There are approximately 1 million glomeruli, or filters, in each kidney. The glomerulus is attached to the opening of a small fluid-collecting tube called a tubule. Blood is filtered in the glomerulus, and extra water and wastes pass into the tubule and become urine. Eventually, the urine drains from the kidneys into the bladder through larger tubes called ureters.
Each glomerulus-and-tubule unit is called a nephron. Each kidney is composed of about 1 million nephrons. In healthy nephrons, the glomerular membrane that separates the blood vessel from the tubule allows waste products and extra water to pass into the tubule while keeping blood cells and protein in the bloodstream.
The signs and symptoms of glomerular disease include:
- Proteinuria: large amounts of protein in the urine
- Hematuria: blood in the urine
- Reduced glomerular filtration rate: inefficient filtering of wastes from the blood
- Hypoproteinemia: low blood protein
- Edema: swelling in parts of the body
One or more of these symptoms can be the first sign of kidney disease. But how would you know, for example, whether you have proteinuria? Before seeing a doctor, you may not. But some of these symptoms have signs, or visible manifestations:
- Proteinuria may cause foamy urine. Blood may cause the urine to be pink or cola-colored.
- Edema may be obvious in hands and ankles, especially at the end of the day, or around the eyes when awakening in the morning, for example.
- The kidneys filter waste and extra fluid from the blood.
- The filtering process takes place in the nephron, where microscopic blood vessel filters, called glomeruli, are attached to fluid-collecting tubules.
- A number of different disease processes can damage the glomeruli and thereby cause kidney failure. Glomerulonephritis and glomerulosclerosis are broad terms that include many forms of damage to the glomeruli.
- Some forms of kidney failure can be slowed down, but scarred glomeruli can never be repaired.
- Treatment for the early stages of kidney failure depends on the disease causing the damage.
- Early signs of kidney failure include blood or protein in the urine and swelling in the hands, feet, abdomen, or face. Kidney failure may be silent for many years.
Types of Glomerular Diseases
Goodpasture Syndrome is an uncommon disease that affects both the kidneys and the lungs. If you have the disease, usually you will:
- Bleed from the lungs
- Cough up blood
- Have inflamed kidneys (glomerulonephritis).
Usually, symptoms will occur because your body is making antibodies that hurt the lining of your lungs and kidneys. It is not known why your antibodies begin to attack your own body. Usually they only do helpful things such as fight infections. This problem is most common in people between the ages of 15 and 35 or after age 55. It is not contagious and it is more common in men and Caucasians. Goodpasture Syndrome may cause life-threatening bleeding in the lungs, but does not usually cause long-term damage in that area. The harm done to your kidneys, however, can result in kidney failure. Early diagnosis and treatment are the best ways to prevent kidney damage. Your doctor will give you medicine that will fight the harmful antibodies. The doctor may suggest that you undergo a special blood filtering process (plasmapheresis) to remove harmful antibodies. Usually, your body will make the antibodies for a short time, anywhere from a few weeks to two years. Once this stops, you should not have any more problems with your lungs. However, your kidneys may have been harmed a little or a lot.
High Blood Pressure
In recent years, researchers have learned a great deal about kidney disease. NIDDK sponsors several programs aimed at understanding kidney failure and finding treatments to stop its progression.
NIDDK's Division of Kidney, Urologic, and Hematologic Diseases supports basic research into normal kidney function and the diseases that impair normal function at the cellular and molecular levels, including diabetes, high blood pressure, glomerulonephritis, and polycystic kidney disease.
About High Blood Pressure
Another sign is proteinuria, or protein in your urine. Proteinuria has also been shown to be associated with heart disease and damaged blood vessels.
High blood pressure is one of the leading causes of kidney failure, also commonly called end-stage renal disease (ESRD). People with kidney failure must either receive a kidney transplant or go on dialysis. Every year, high blood pressure causes more than 25,000 new cases of kidney failure in the United States.
NHLBI has found that six lifestyle changes can help control blood pressure:
- Maintain your weight at a level close to normal. Choose fruits, vegetables, grains, and low-fat dairy foods.
- Limit your daily sodium (salt) intake to 2,000 milligrams or lower if you already have high blood pressure. Read nutrition labels on packaged foods to learn how much sodium is in one serving. Keep a sodium diary.
- Get plenty of exercise, which means at least 30 minutes of moderate activity, such as walking, most days of the week.
- Avoid consuming too much alcohol. Men should limit consumption to two drinks (two 12-ounce servings of beer or two 5-ounce servings of wine or two 1.5-ounce servings of "hard” liquor) a day. Women should have no more than a single serving on a given day because metabolic differences make women more susceptible to the effects of alcohol.
- Limit caffeine intake.
- Quit cigarette smoking.
People with diabetes also have a substantially increased risk for developing kidney failure. People who are at risk both because of their race and because of diabetes should have early management of high blood pressure.
The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), also part of NIH, sponsored the African American Study of Kidney Disease and Hypertension (AASK) to find effective ways to prevent high blood pressure and kidney failure in this population. The results, released in 2003, showed that an ACE inhibitor was better at slowing the progression of kidney disease in African Americans than either of two other drugs.
About Kidney Stones
If you have a kidney stone, you may already know how painful it can be. Most kidney stones pass out of the body without help from a doctor. But sometimes a stone will not just go away. It may even get larger. Your doctor can help.
You should call a doctor when you have:
- Extreme pain in your back or side that will not go away
- Blood in your urine
- Fever and chills
- Urine that smells bad or looks cloudy
- A burning feeling when you urinate
These may be signs of a kidney stone that needs a doctor's care.
No. There are four major types of kidney stones.
- The most common type of stone contains calcium (KAL-see-um). Calcium is a normal part of a healthy diet. Calcium that is not used by the bones and muscles goes to the kidneys. In most people, the kidneys flush out the extra calcium with the rest of the urine. People who have calcium stones keep the calcium in their kidneys. The calcium that stays behind joins with other waste products to form a stone.
- A struvite (STROO-vite) stone may form after an infection in the urinary system. These stones contain the mineral magnesium (mag-NEE-zee-um) and the waste product ammonia (uh-MOH-nyuh).
- A uric (YOOR-ik) acid stone may form when there is too much acid in the urine. If you tend to form uric acid stones, you may need to cut back on the amount of meat you eat.
- Cystine (SIS-teen) stones are rare. Cystine is one of the building blocks that make up muscles, nerves, and other parts of the body. Cystine can build up in the urine to form a stone. The disease that causes cystine stones runs in families.
Now, doctors have new ways to remove problem stones. The following section describes a few of these methods.
Your doctor can use a machine to send shock waves directly to the kidney stone. The shock waves break a large stone into small stones that will pass through your urinary system with your urine.
Two types of shock wave machines exist. With one machine, you sit in a tub of water. With the other type of machine, you lie on a table. The full name for this method is extracorporeal (EKS-truh-kor-POR-ee-ul) shockwave lithotripsy (LITH-oh-TRIP-see). Doctors often call it ESWL for short. Lithotripsy is a Greek word that means stone crushing.
In this method, the doctor makes a small cut into the patient's back and makes a narrow tunnel through the skin to the stone inside the kidney. With a special instrument that goes through the tunnel, the doctor can find the stone and remove it. The technical name for this method is percutaneous (PER-kyoo-TAY-nee-us) nephrolithotomy (NEF-roh-lih-THAH-tuh-mee).
A ureteroscope (yoo-REE-ter-uh-scope) looks like a long wire. The doctor inserts it into the patient's urethra, passes it up through the bladder, and directs it to the ureter where the stone is located. The ureteroscope has a camera that allows the doctor to see the stone. A cage is used to catch the stone and pull it out, or the doctor may destroy it with a device inserted through the ureteroscope. Ask your doctor which method is right for you.
Your doctor may ask you to eat more of some foods and to cut back on other foods. For example, if you have a uric acid stone, your doctor may ask you to eat less meat, because meat breaks down to make uric acid. The doctor may give you medicines to prevent calcium and uric acid stones.
View the Kidney Stone Oxalate Diet (PDF)
- Most stones will pass out of the body without a doctor's help.
- See your doctor if you have severe pain in your back or side that will not go away.
- See your doctor if you have blood in your urine (urine will appear pink).
- Drink lots of water to prevent more kidney stones from forming.
- When you pass a stone, try to catch it in a strainer to show to your doctor.
- Talk to your doctor about how to avoid more stones.
Renal and Pancreas Transplant
Barbara A. Bresnahan, MD
Ehab R. Saad, MD, FACP, FASN, MA
Liliana Osadchuk, MD
A simultaneous kidney-pancreas transplant (SKP) is an operation to place both a kidney and a pancreas – at the same time – into someone who has kidney failure-related diabetes. In many cases, both transplanted organs may come from the same deceased (nonliving) donor (someone who died recently). However, it is also possible for the kidney to come from a living donor (a family member or friend) and the pancreas from a deceased (nonliving) donor.
Although in most cases, both transplanted organs come from the same deceased donor, in certain cases it is also possible for the kidney to come from a living donor (a family member or friend), and the pancreas from a deceased donor. The procedure treats both kidney failure and diabetes because the new organs replace the function of the failed kidney and the pancreas.
View Froedtert Hospital's Pancreas Transplant site for more information
View Froedtert Hospital's Kidney Transplant site for more information
About Renal and Pancreas Transplants
There are certain medical situations in which a kidney-pancreas transplant is usually not an option:
- Untreated cancer and cancer that has spread
- Severe mental health diagnoses
- Substance abuse
- Severe mental retardation
- Severe coronary artery disease and/or congestive heart failure
The best results are usually achieved with a closely matched kidney from a living Donor (usually from a brother or a sister). Statistics show that the next best results are achieved with a kidney from a less closely matched living donor (such as a spouse or friend). The success rates are also good for combined kidney-pancreas transplants from deceased donors. The best results are usually achieved when both the pancreas and a kidney come from the same donor: a deceased donor. This is because the risk of rejection is significantly reduced. However, there have been several transplants performed using a living donor, with one kidney and a pancreas segment being donated.
The surgical procedure usually lasts four to six hours, and your hospital stay is typically one to two weeks. Once connected, the pancreas begins to make insulin within hours, and the blood sugar is normalized. From this point on, insulin shots are usually not required unless the body rejects the new pancreas. Studies show that the new pancreas may help slow the progression of other problems related to diabetes, such as nerve and eye damage, and decrease the chance that diabetic changes may occur in the transplanted kidney.
If you have any of these symptoms, speak to your transplant team right away. You will be evaluated regularly at the transplant center. Sometimes, early symptoms of rejection are hard to notice, but they can be detected in your blood work and treated. Most kidney-pancreas transplant patients will have a rejection episode during the first few months, and they will need to return to the hospital for treatment.
The medications you need to take to prevent rejection lower your body's immune defenses, which increases your chance of getting an infection. This risk is higher right after your transplant because the doses of your medications are higher. During this time, it is important to avoid large crowds and people who are sick, especially with contagious illnesses such as colds or flu. You should wash your hands often. After a while, the doses of your medications will be reduced, and the chance of getting infections will be less.
After your transplant, you will be feeling better and looking forward to returning to your normal lifestyle. A major part of that normal lifestyle is the ability to enjoy eating again. However, some of the drugs you will be taking after your transplant affect the way your body processes food. This may cause you to eat more, causing you to gain weight.
Excessive weight gain can be harmful to your health because it increases the risk of heart disease, diabetes and high blood pressure. The following tips may help you avoid unwanted weight gain:
- Eat a balanced diet with plenty of fruits and vegetables.
- Eat a minimum amount of salt, processed foods and snacks.
- Use herbs and spices to add flavor, instead of salt.
- Watch your food intake and drink plenty of water (unless you are told to limit fluids).
- Try to eat high-fiber foods, such as raw vegetables and fruits, which make you feel full.
- Add calcium to your diet by eating calcium-rich foods, such as low-fat dairy products and green, leafy vegetables or calcium supplements.
- Eat as little fat and oil as possible.
- Read food labels so that you can be smart when food shopping.
- Become more aware of serving sizes that are listed on food labels.
- Because protein helps your build muscles and tissue, which will help you heal after surgery, eat foods high in protein, such as meat, poultry (i.e. chicken), fish, eggs, nuts (without salt) and beans.
- Select healthier condiments, such as mustard, and low-fat mayonnaise and salad dressings.
- Choose healthy cooking methods. Instead of frying, try baking, grilling, broiling or steaming foods. And instead of oil, use nonstick, fat-free spray or sauces.
- When dining out, try to eat smaller portions and avoid high-fat entrees.
- Don't drink alcohol or use any drugs that aren’t prescribed by your physician, as these may harm your new organ. If you have a problem with drugs or alcohol, talk with your social worker, who can help arrange for counseling and other support services.
As you start to feel better, regular exercise will help you regain your strength. Because you may feel tired at first, you should take rest breaks during exercise. Gradually, increase the amount and type of physical activity you enjoy.