Renal failure
When your kidneys lose the ability to filter waste from your blood, dangerous levels of fluid and toxins can build up in your body. Understanding this serious condition and the available treatments can help you take charge of your health and maintain a good quality of life.
Table of contents
- What is renal failure?
- Types of renal failure
- Stages of kidney disease
- Signs and symptoms
- Causes
- Diagnosis
- Treatment options
- Living with kidney failure
- Prevention
kidney failure, end-stage renal disease, ESRD, end-stage kidney disease, ESKD
What is renal failure?
Renal failure, also known as kidney failure, is a medical condition in which your kidneys no longer work well enough to keep you alive[1]. When your kidneys fail, they can no longer adequately filter waste products from your blood, functioning at less than 15 percent of normal levels[7].
Your kidneys are bean-shaped organs about the size of your fist that sit under your ribcage, toward your back[1]. One of their most important jobs is helping your body eliminate toxins. Your kidneys filter your blood and send waste products out of your body in urine. They also balance the amount of fluids, electrolytes and minerals in your body, make hormones that control blood pressure, create red blood cells, and keep your bones strong[1][8].
When your kidneys don’t work correctly, waste products and extra fluid build up in your body. If this happens, you’ll feel sick and eventually die without treatment[1]. However, many people can manage kidney failure with proper treatment and maintain a good quality of life[1].
Types of renal failure
There are two main types of kidney failure, classified by how they develop and whether the damage can be reversed[4].
Acute kidney failure
Acute kidney failure (also called acute kidney injury) is when you lose kidney function quickly, over a few hours or days[4]. Kidney failure is sometimes temporary and develops quickly. It can be mild, or severe enough to cause complete kidney failure. Many people with acute kidney injury will recover over time. This could take days, weeks or months[4]. However, for some people, acute kidney injury can cause death, or it can cause permanent damage and lead to chronic kidney disease[4].
Chronic kidney failure
Chronic kidney failure (or chronic kidney disease) is when your kidneys have been damaged in a way that can’t be reversed[4]. It’s a long-term condition that slowly gets worse over time[1]. Chronic kidney disease takes months or years to develop. If chronic kidney disease gets worse, it can lead to chronic kidney failure[4].
Kidney failure affects over 750,000 people in the United States each year and around 2 million people worldwide[1].
Stages of kidney disease
There are five stages of kidney disease according to your estimated glomerular filtration rate (eGFR), which is a blood test[1]. Your eGFR is a calculation of how well your kidneys filter substances. A normal eGFR is above 90. The lowest eGFR is 0, which means there’s no remaining kidney function[1].
The five stages are:
- Stage I: Your GFR is higher than 90. At this stage, your kidneys have mild damage but still function normally[1].
- Stage II: Your GFR may be as low as 60 or as high as 89. You have more damage to your kidneys than in stage I, but they still function well[1].
- Stage III: Your GFR may be as low as 30 or as high as 59. You may have mild or severe loss of kidney function[1].
- Stage IV: Your GFR may be as low as 15 or as high as 29. You have severe loss of kidney function[1].
- Stage V: Your GFR is below 15. Your kidneys are nearing or at complete failure. Generally, this is when you would start to have symptoms[1].
Kidney failure can worsen to the most severe stage, end-stage kidney disease (ESKD), which is deadly without treatment. If you have end-stage kidney disease, you may survive a few days or weeks without treatment[1].
Signs and symptoms
Many people experience few or no symptoms in the early stages of kidney disease. However, chronic kidney disease may still cause damage even though you feel fine[1]. Symptoms of kidney failure may begin so slowly that you don’t notice them right away[8].
Common symptoms of kidney failure
If your kidneys aren’t working properly, you may notice one or more of the following signs[1]:
- Extreme tiredness (fatigue)
- Nausea and vomiting
- Confusion or trouble concentrating
- Swelling (edema), particularly around your hands, ankles or face
- Changes in how often you urinate (pee)
- Muscle cramps (muscle spasms)
- Dry or itchy skin
- Poor appetite, or food may taste metallic
Acute kidney failure symptoms
The first symptom of acute kidney failure is a decreased amount of urine[4]. Early symptoms may include swelling, weight gain and changes in blood test results. Late symptoms may include tiredness, trouble concentrating, confusion, changes in your breathing and seizures[4].
See your doctor urgently or go to your local hospital emergency department if you notice you are suddenly making less urine than usual together with other symptoms of acute kidney failure[4].
Advanced kidney failure symptoms
As kidney failure develops, additional symptoms may include worsening swelling, including fluid build-up in your lungs and abdomen[4]. Other symptoms can include shortness of breath if fluid builds up in the lungs, chest pain if fluid builds up around the lining of the heart, and loss of appetite[5].
Causes
Diabetes and high blood pressure are the most common causes of chronic kidney disease and kidney failure[1].
Main causes of chronic kidney failure
Chronic kidney disease is usually caused by other conditions that put a strain on the kidneys. Often it’s the result of a combination of different problems[9]. Common causes include:
- High blood pressure – Over time, this can put strain on the small blood vessels in the kidneys and stop the kidneys working properly[9]
- Diabetes – Too much glucose in your blood can damage the tiny filters in the kidneys[9]
- High cholesterol – This can cause a build-up of fatty deposits in the blood vessels supplying your kidneys, which can make it harder for them to work properly[9]
- Kidney infections
- Glomerulonephritis – kidney inflammation[9]
- Polycystic kidney disease – an inherited condition where growths called cysts develop in the kidneys[9]
- Blockages in the flow of urine – for example, from kidney stones that keep coming back, or an enlarged prostate[9]
- Long-term, regular use of certain medicines – such as lithium and non-steroidal anti-inflammatory drugs (NSAIDs)[9]
Causes of acute kidney failure
Causes of acute kidney failure include low blood pressure, blockage of the urinary tract, certain medications, muscle breakdown, and hemolytic uremic syndrome[7].
Diagnosis
Chronic kidney disease can be diagnosed using blood and urine tests. These tests look for high levels of certain substances in your blood and urine that are signs your kidneys are not working properly[9].
Early kidney disease may not have any symptoms, so getting tested may be the only way to know your kidneys are healthy[8]. If you’re at a high risk of developing kidney disease (for example, you have a known risk factor such as high blood pressure or diabetes), you may be advised to have regular tests to check for chronic kidney disease so it’s found at an early stage[9].
The results of your blood and urine tests can be used to tell the stage of your kidney disease. This is a number that reflects how severe the damage to your kidneys is, with a higher number indicating more serious chronic kidney disease[9].
Tests may include:
- Blood tests: A sample of your blood may show fast-rising levels of urea and creatinine. This helps show how your kidneys are working[18].
- Urine output measures: Measuring how much urine you pass in 24 hours may help find the cause of your kidney failure[18].
- Urine tests: A sample of your urine may show something that suggests a condition that might explain kidney failure[18].
- Imaging tests: Imaging tests such as ultrasound and CT scans can show your kidneys[18].
- Kidney biopsy: Your healthcare professional may suggest removing a small sample of your kidney tissue for lab testing. A needle put through your skin and into your kidney removes the sample[18].
Treatment options
There’s no cure for chronic kidney disease, but treatment can help relieve the symptoms and stop it getting worse[9]. Your treatment will depend on how severe your condition is[9].
Treatment for kidney failure means you need dialysis or a kidney transplant to stay alive[1]. Some people choose to opt for conservative care (also called supportive care or palliative care) to manage their symptoms, aiming for the best quality of life during their remaining time[1].
Main treatment approaches
The main treatments are[9]:
- Lifestyle changes to help you remain as healthy as possible
- Medicine to control associated problems such as high blood pressure and high cholesterol
- Dialysis – treatment to replicate some of the kidney’s functions; this may be necessary in advanced chronic kidney disease
- Kidney transplant – this may also be necessary in advanced chronic kidney disease
Dialysis
There are two different types of dialysis[11]:
- Hemodialysis – This is done through cleaning the blood through a machine, which you attend a dialysis center three times a week for about four hours each time. It can be done at home in certain circumstances[11].
- Peritoneal dialysis – Fluid gets put into your tummy, takes out the toxins and is drained. This can be done either during the day or overnight on a machine[11].
Home dialysis offers you more flexibility to exercise, work and travel, and gives you more freedom with what you can eat and drink because the dialysis occurs more often[25].
Kidney transplant
A kidney transplant offers the potential for a more active and longer life, and reduces the need for dietary and fluid restrictions[25]. Unfortunately, a transplant is not suitable for everyone and there are not enough kidneys available for people who are on the waiting list[25].
Medications
There’s no medicine specifically for chronic kidney disease, but medicine can help control many of the problems that cause the condition and the complications that can happen as a result of it[15]. You may need to take medicine to treat or prevent different problems caused by chronic kidney disease, including:
- Medicines for high blood pressure, such as ACE inhibitors
- Statins for high cholesterol
- Medicines for diabetes or high ACR
- Medicines for high potassium levels
It’s very important that you take any prescribed medicine, even if you do not feel unwell. Some medicines are designed to prevent serious problems from happening in the future[21].
Living with kidney failure
Although dialysis or transplant surgery after kidney failure can be challenging, many people go on to live active and productive lives[25]. Taking an active role in managing chronic kidney disease will help you feel better and improve your overall well-being[23].
Lifestyle changes
You can take several steps to help you stay healthy with kidney failure:
Make healthy food choices: Choose foods that are healthy for your heart and your entire body, including fresh fruits, fresh or frozen vegetables, whole grains, and low-fat or fat-free dairy products. Eat healthy meals, and cut back on salt and added sugars. Aim for less than 2,300 milligrams of sodium each day[22]. While you should limit salt, your food doesn’t have to be bland. Get creative with herbs, spices, mustard, and flavored vinegars in your favorite recipes[23].
Be physically active: Regular physical activity can help improve your general health. Physical activity is good for anyone with kidney disease, whether you have mild, moderate, or severe chronic kidney disease. It can boost your energy, help you sleep, strengthen your bones, and help prevent depression. It may also reduce your risk of problems such as heart disease[23].
Stop smoking: If you smoke, stopping smoking can improve your overall health and reduce your risk of many other health problems[21].
Limit alcohol: You may still be able to drink alcohol if you have kidney disease, but it’s advisable not to exceed the recommended limits of more than 14 alcohol units a week[21].
Get vaccinated: Kidney disease can put a significant strain on your body and make you more vulnerable to infections. Everyone with the condition is encouraged to have the annual flu jab and the one-off pneumococcal vaccination[21].
Managing related health conditions
Keep your blood pressure below 140/90 mm Hg (or the target set by your doctor). If you have diabetes, stay in your target blood sugar range as much as possible[23].
Regular monitoring
You’ll have regular contact with your care team to monitor your condition. You’ll also be advised to have regular check-ups to monitor your condition[9].
Mental health and support
Kidney failure may affect your day-to-day activities and may change your relationships with friends and family, and how you feel. Ask questions and take notes during your health care appointments. The more you know about what to expect, the better you’ll be able to prepare and take charge of your treatment[8].
Prevention
You can help prevent chronic kidney disease by preventing or managing health conditions that cause kidney damage, such as diabetes and high blood pressure[22]. The steps described below may help keep your whole body healthy, including your kidneys[22].
You can protect your kidneys by:
- Controlling blood sugar if you have diabetes
- Managing high blood pressure
- Maintaining a healthy weight
- Eating a healthy, balanced diet
- Exercising regularly – aim to do at least 150 minutes a week[15]
- Not smoking
- Limiting alcohol intake
- Avoiding over-the-counter non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, except when advised to by a medical professional – these medicines can harm your kidneys if you have kidney disease[15]
During your next medical visit, you may want to ask your health care provider about your kidney health. Early kidney disease may not have any symptoms, so getting tested may be the only way to know your kidneys are healthy[8].
See a provider right away if you develop a urinary tract infection (UTI), which can cause kidney damage if left untreated[22].
While it’s not possible to repair damage that has already happened to your kidneys, chronic kidney disease will not necessarily get worse. Chronic kidney disease only reaches an advanced stage in a small proportion of people[21].
