It is a slight and progressive decrease in kidney function. It is usually the result of a complication from another serious medical condition.
It is also known as chronic kidney failure or chronic kidney disease (CKD).
Unlike acute kidney failure, which occurs quickly and suddenly, chronic kidney failure occurs gradually over weeks, months, or years, as the kidneys slowly stop working and end-stage kidney disease develops. (ESRD).
Progression is so slow that symptoms usually do not appear until significant damage occurs.
The kidneys play three leading roles:
- We eliminate waste products from the body, preventing toxins from accumulating in the bloodstream.
- Producing hormones that control other bodily functions, such as blood pressure regulation and the production of red blood cells.
- We regulate the levels of minerals or electrolytes (e.g., sodium, calcium, and potassium) and fluids in the body.
The two kidneys in our body have tiny filtering units, called nephrons, each of which is made up of a glomerulus (which acts as a kind of sieve to prevent essential components, such as red blood cells, from being removed) and a tubule (the tube through which the fluid passes).
It is entirely possible to live a whole and healthy life with just one kidney; one fully functioning kidney can do the work of two, but it is essential to watch for signs of any problems with the remaining kidney.
When the kidneys get to the point where they can’t function, kidney dialysis or a transplant is the only way to remove waste products from the body.
Causes of kidney failure
The most common cause of end-stage kidney failure worldwide is IgA nephropathy (an inflammatory kidney disease).
One of the complications that result from diabetes or high blood pressure is damage to the small blood vessels in the body. Blood vessels in the kidneys are also damaged, leading to CKD.
Other common causes of chronic kidney failure include:
- Recurrent pyelonephritis (kidney infection).
- Polycystic kidney disease (multiple cysts in the kidneys).
- Autoimmune disorders such as systemic lupus erythematosus.
- Hardening of the arteries can damage the blood vessels in the kidney.
- Urinary tract blockages and reflux due to frequent infections, stones, or an anatomical abnormality at birth.
- Excessive use of drugs that are metabolized through the kidneys.
Symptoms and complications
Chronic kidney failure can occur for many years before you notice any symptoms. If your doctor suspects that you will likely develop kidney failure, they will probably catch it early by doing regular blood and urine tests.
Without regular monitoring, symptoms may not be detected until the kidneys have been damaged. Some of the symptoms, such as fatigue, may have been present for some time, but they can appear so gradually that they are not noticed or are attributed to kidney failure.
Some signs of chronic kidney failure are more obvious than others. These are:
- Increased urination, especially at night.
- Decreased urination
- Blood in the urine (not a common symptom of chronic kidney failure).
- Cloudy or tea-colored urine.
Other symptoms are not so obvious but are a direct result of the kidneys’ inability to remove waste and excess fluid from the body:
- Swollen eyes, hands, and feet (called edema).
- High blood pressure
- Difficulty breathing.
- Loss of appetite
- Nausea and vomiting (this is a common symptom).
- Bad taste in the mouth or bad breath.
- Persistent and generalized itchy skin.
- Muscle spasms or cramps
- A yellowish-brown tint to the skin.
As kidney failure worsens and toxins build up in the body, seizures and mental confusion can occur.
Being diagnosed with chronic kidney failure can be very scary. However, the future of the condition depends on the medical problem that caused the kidney failure, the amount of kidney damage, and the complications, if any.
Some of these complications can include:
- High blood pressure (hypertension).
- Increased risk of bleeding
- Increased risk of infection.
- Fluid overload (called edema).
- Electrolyte abnormalities (for example, hyperkalemia, high potassium levels in the blood).
- Mineral abnormalities (for example, hypercalcemia [high levels of calcium in the blood] or hyperphosphatemia [high levels of phosphorus in the blood]).
- Fragile bones.
Diagnosis of kidney failure
After taking a complete history, your doctor will check for some or all of the following:
- General appearance (in severe cases of CKD, people may have muscle wasting and weakness).
- Blood pressure (many people with chronic kidney failure have high blood pressure).
- Urine tests (to check for excess proteinuria in the urine).
- Blood test.
- X-rays of the kidneys.
- Abdominal computed tomography or CAT (computed tomography) scan.
- Abdominal MRI (magnetic resonance imaging)
- Abdominal ultrasound
- Kidney scan.
X-rays, scans, and ultrasounds check for kidney abnormalities, such as small size, tumors, or blockages. These various tests will allow the doctor to recognize if there is any abnormal kidney function and diagnose CKD.
Treatment and prevention
Initially, people with kidney failure are generally advised to change their diet.
A low-protein diet (0.8-1g / kg/day) is often recommended to help decrease waste build-up in the body and help limit nausea and vomiting that can accompany chronic kidney failure.
A qualified dietitian can help determine the proper diet. The underlying disease (s) must be considered when making any dietary changes.
Because the kidneys do not remove body waste as effectively as they should, the levels of electrolytes (sodium and potassium) and minerals (calcium and phosphate) in your body may rise too high (most common) or be removed too quickly.
Regular blood tests measure these electrolytes and minerals, and if the levels are out of balance, dietary changes may be recommended. Occasionally, a doctor suggests taking supplements or medications to help control the imbalance.
If the kidneys do not allow the body to remove excess fluid, it may be necessary to restrict fluid intake. This is so your kidneys and heart don’t have to work so hard.
The amount of fluid allowed can be determined in advance, but a day’s allowance is often based on the amount of urine emitted the day before. For example, someone who passes 500 ml of urine in one day may drink 500 ml of fluid in the next 24 hours, and so on.
Fluid restrictions are usually only used in severe cases of swelling or if kidney failure has progressed to end-stage renal failure and dialysis has become necessary.
Dietitians can help organize diets around fluid restrictions and teach what is allowed and what should be avoided.
If the kidneys continue to get worse despite treatment, dialysis or a kidney transplant is needed.
There are two types of dialysis: peritoneal dialysis and hemodialysis.
Dialysis is a process that removes excess fluids and waste using a membrane instead of a kidney as a filter. The type of dialysis depends on many factors, including a person’s lifestyle.
Dialysis is not a cure, and people on dialysis must still follow special diets, reduce their fluids, and take medications as prescribed by their doctors.
Peritoneal dialysis uses the natural membrane of the abdominal cavity as its filter. It can only be used by people who have not had major abdominal surgery.
Using a catheter (a tiny, flexible tube) that has been permanently placed in the abdomen, the abdominal cavity is filled with a solution called dialysate, which remains there for a set time. The dialysate draws waste and excess fluid from the bloodstream through the membrane.
When finished, the dialysate, now with the extra body fluid and waste mixed in, is drained and then replaced with fresh dialysate. Usually done at home, this procedure is continuous and done in cycles.
Peritoneal dialysis can be done by yourself or by a family member. It is done daily, but the frequency of cycles during the day varies according to the type of peritoneal dialysis performed.
Cycles can occur as often as every few hours, or the procedure can span the entire night using a bicycle that automatically exchanges fluid while the person sleeps.
Peritoneal dialysis doesn’t work for everyone, and over time, it may stop working effectively for those who use it. If this happens, hemodialysis is necessary.
Hemodialysis is a procedure that must be done in a hospital or particular clinic setting. With hemodialysis, waste and excess body fluids are filtered through the blood using a dialyzer, a coiled membrane of hundreds of hollow fibers.
A dialysis machine pumps blood through the dialyzer. Blood remains on one side of the membrane, while dialysate is on the other side of the membrane.
As with peritoneal dialysis, the dialysate draws extra body fluid and waste through the filter, and then the filtered blood is pumped back into the body.
The hemodialysis process is faster than peritoneal dialysis, and the cycle is usually completed in about four hours. It is generally done about three times a week.
A kidney transplant is a solution for some people with chronic kidney failure. All people with this condition are evaluated for a kidney transplant.
However, some with other severe conditions may be at higher risk of complications from surgery or anti-rejection medications, so a transplant may not be an appropriate option for them.
A kidney can be transplanted from a living donor (often a relative) or a donor who recently died and left their organs for donation. A kidney recipient can lead a healthy life for many years with a successful transplant and proper medical care.
Chronic kidney failure often causes anemia, a condition in which there are not enough healthy red blood cells in the body. For some people with anemia caused by chronic kidney failure, their doctor may advise them to take medications that treat anemia by stimulating the body to make more red blood cells.
Prevention of chronic kidney failure should begin long before signs of kidney failure are noticed. Many people with CKD will develop cardiovascular disease.
Because chronic kidney failure and cardiovascular disease share some of the same risk factors, for example, diabetes and high blood pressure, it is essential to control these risk factors for cardiovascular disease to manage CKD effectively.
This involves maintaining reasonable blood pressure control and keeping your blood sugar levels under control if you have diabetes.
Doctors may also suggest specific lifestyle changes, such as quitting smoking, eating a healthy diet (e.g., reducing salt intake), and exercising regularly.
People with chronic kidney failure who also have high blood pressure often start with medications known as angiotensin-converting enzyme inhibitors (ACE inhibitors, such as ramipril and perindopril) or angiotensin receptor blockers (ARBs, candesartan, losartan, valsartan).
These medications help lower blood pressure and slow the progression of kidney dysfunction by reducing protein in the urine and pressure on the kidneys that would otherwise cause significant damage. People with diabetic CKD can also benefit from these medications.
People at high risk of developing chronic kidney failure should be aware of the potential risks. They should also be taught how to take steps to prevent kidney failure and recognize some of the warning signs.
While there is no cure, steps can be taken to reduce complications and symptoms.
Some ways to prevent or delay the onset of chronic kidney failure are:
Manage risk factors for cardiovascular diseases such as:
- Avoid smoking: For people with diabetes, smoking can accelerate damage to the small blood vessels in the body.
- Check your blood pressure regularly and ask what your target blood pressure should be.
- Maintain a healthy diet and exercise regularly.
- Restrict alcohol consumption.
- Follow recommended treatments for chronic conditions like diabetes, lupus, and high blood pressure.
- Don’t abuse prescription or over-the-counter drugs; ask the pharmacist which medications are safe to use and will not cause further damage to the kidneys.
- Get treatment for urinary tract infections or any urinary problem as soon as possible.
- People with impaired kidney function should be aware that medications that the body removes from the body primarily through the kidneys have an increased risk of build-up or side effects (e.g., Magnesium, NSAIDs, metformin).