Our bodies have several vital organs that quietly toil away to keep us functioning properly. Among these are the kidneys, two fist-sized organs that sit on either side of the spine below the ribs.
The kidneys are shaped like beans — kidney beans, naturally — and spend their days balancing your electrolyte levels and filtering the blood to remove waste. This waste is then passed into the urine and flows out of the body. All of the blood in your body moves through the kidneys several times each day to be cleansed. It’s a big job, and any problems with kidney function can lead to serious health issues. In fact, several kidney diseases can be life threatening.
[SEE: 9 Symptoms of a Kidney Problem.]
What Is Kidney Disease?
Kidney disease occurs when the kidneys are unable to effectively clear the blood of toxins.
The glomeruli, tiny filters in the kidneys, are essential for this process. If they aren’t working optimally or become blocked from doing their job, a buildup of waste and fluid can result, making you sick.
While having two healthy kidneys is ideal, most people can lead healthy lives with just one functioning kidney. Some people are born with only one working kidney, while others may have a kidney removed, such as for donating to someone who needs a transplant.
[See: 5 Ways to Reduce Your Risk of Developing Kidney Disease.]
Types of Kidney Disease
There are several types of kidney disease, including:
Chronic kidney disease
Chronic kidney disease, or CKD, is a progressive condition in which the kidneys are damaged and unable to filter blood properly. Over time, this can lead to an increase of waste and fluids in the body, contributing to a range of health complications, such as anemia and heart disease.
While CKD is both progressive and incurable, it can be effectively managed. Seeking care early — especially if you’re at risk of developing this condition or think you’re experiencing symptoms — is critical, as early diagnosis and treatment can slow the progression of the disease, help preserve kidney function and improve overall quality of life.
CKD is the most common form of kidney disease, affecting approximately 35 million Americans, according to the Centers for Disease Control and Prevention.
Other types of kidney disease
In addition to CKD, there are several other common types of kidney disease that can be either chronic or acute, such as:
— Glomerulonephritis. This kidney disease develops when the glomeruli, those tiny filters that remove waste from the body, become inflamed or damaged and no longer function properly. Acute forms of the disease can develop from a strep infection that’s not been treated properly or from other infections.
— Autoimmune disease-related kidney disease. Certain autoimmune diseases, such as lupus or rheumatoid arthritis, cause the immune system to attack the body’s own cells. When this process affects the kidneys, it can lead to reduced kidney function. This process can be acute or chronic and is often treated using steroids or other immunosuppressant medications that get the immune system to stop attacking the body’s cells.
— Polycystic kidney disease. This inherited disorder leads to the development of fluid-filled cysts all over the kidneys, causing the organs to grow too large and lose function. It’s a progressive, incurable disease, but it can be managed with a growing number of medications.
Rare kidney diseases
Several rare diseases can also affect the kidneys, such as:
— Alport syndrome. This genetic disease is caused by problems on three genes that control how certain body parts are shaped. It causes the kidneys, eyes and ears to grow abnormally. As such, kidney disease, vision loss and hearing loss can result. Blood in the urine is often the first sign of the disease.
— Goodpasture syndrome. Also known as anti-glomerular basement membrane disease, Goodpasture syndrome is a rare autoimmune disease in which the immune system attacks a membrane in the kidneys and lungs, causing bleeding from the lungs and acute kidney failure. The disease can progress very quickly but can be managed with steroids and other immunosuppressant medications that stop the immune system from attacking the body’s tissues.
— Wegener’s granulomatosis. Also called granulomatosis with polyangiitis, this rare disease causes inflammation of the blood vessels in the nose, sinuses, throat, lungs and kidneys. It’s a type of vasculitis that slows blood flow to the kidneys. Discharge from the nose, nosebleeds and sinus infections along with fever and blood in the urine could signal this rare disease. The disease tends to worsen very quickly, but it can be treated with medications.
Causes of Kidney Disease
Chronic kidney disease can result from a number of causes, including:
High blood pressure
High blood pressure, the number one cause of chronic kidney disease, according to the National Kidney Foundation, can damage blood vessels, which can reduce the blood supply to the kidneys. High blood pressure also damages the glomeruli, the tiny filters in your kidneys.
Patients with high blood pressure should be regularly screened to see if their kidneys are affected, says Dr. Brad Rovin, director of the division of nephrology at the Ohio State University Wexner Medical Center and clinical professor of internal medicine at the Ohio State University College of Medicine, says
Diabetes
Similarly, the effects of diabetes on the body over time also contribute to the development of kidney disease. Frequent high blood sugar levels cause damage to many internal organs at the cellular level. The kidneys are especially susceptible to this damage and may stop functioning properly.
Rovin notes that the diabetes connection with kidney disease affects people with all types of diabetes. People with either Type 1 or Type 2 diabetes should periodically have their kidney function checked. He says this includes tests to measure their blood chemistry and creatinine levels and looking for protein in the urine.
Cancer
Renal failure can result from kidney cancer or other types of cancer that spread to the kidneys. Kidney damage can also be a side effect of certain cancer treatments, such as chemotherapy agents.
Infections
Infections that may impact the kidneys include:
— Strep bacteria, which, if not properly treated, can lead to a variety of other issues, including inflammation of the kidneys that can impede their function
— Bacterial urinary tract infections, which can eventually reach the kidneys and cause damage
— Certain heart infections, which can travel to the kidneys and wreak havoc
— Viral infections, such as HIV, as well as hepatitis B and hepatitis C — two viruses that first infect the liver and then can progress to the kidneys — that can cause damage to the glomeruli
In all of these cases, management of the original infection can help reduce the chances of developing kidney damage or reducing its severity.
Vasculitis
This condition causes inflammation of the blood vessels. Because the kidneys are highly vascularized, they are sensitive to changes in the health of the vascular system.
Autoimmune diseases
In any kind of autoimmune disease, the body’s immune system — which is designed to protect the body from disease-causing agents — gets confused and begins attacking the body’s own cells. There are a wide range of autoimmune diseases, but some, lupus in particular, can cause damage to the kidneys.
Rovin notes that about 50% of lupus patients are likely to develop kidney problems, such as lupus nephritis, so screening for these issues and staying on top of your health if you have an autoimmune disease is important. Treatment for these types of kidney diseases focuses on controlling the symptoms of the autoimmune disease and getting systemic inflammation under control. Immunosuppressant medications, such as steroids, may help.
Medications
Overuse or abuse of nonsteroidal anti-inflammatory drugs, such as ibuprofen (Advil) and naproxen sodium (Aleve), can also damage the kidneys.
[READ Fact vs. Fiction: Debunking OTC Medication Myths]
Risk Factors for Developing Kidney Disease
Other risk factors for kidney disease include:
— Cardiovascular disease. Heart disease of any type elevates the risk of kidney problems because of how many blood vessels run through the kidneys.
— Obesity. Being overweight puts more strain on many of the body’s organ systems, including the kidneys.
— Smoking. Smoking damages vascular structures throughout the body.
— Family history. Close family members having kidney disease can increase your risk of developing it.
— Race. Black or African Americans, Native Americans and Asian Americans are at higher risk for kidney disease.
— Age. Older adults are at higher risk of losing kidney function.
[Read: How to Prevent Kidney Stones and Improve Kidney Health: Foods to Eat and Avoid]
Symptoms of Kidney Disease
The symptoms of chronic kidney disease can sometimes be challenging to identify initially.
“One of the major issues with kidney disease is a lot of time, patients have no symptoms when it starts out,” Rovin says. “It’s sort of silent. The kidney has a great capacity to compensate for loss of function.”
As a result, it may take a while before symptoms build to a noticeable level.
Early warning signs of CKD may include:
— Nausea and vomiting
— Muscle cramps
— Itching
— Loss of appetite
— Swelling in the lower extremities
— Changes in volume of urine output
— Breathlessness
As the disease progresses and you proceed into kidney failure, more severe symptoms may develop, including:
— Severe abdominal and back pain
— Diarrhea and vomiting
— Fever
— Nosebleeds
— Rashes
High blood pressure that’s unexpected or difficult to control might also be a sign that your kidneys are struggling to do their job, Rovin adds. But it may be difficult to notice because high blood pressure is such a common disorder in the U.S.
[See: Natural Ways to Lower Blood Pressure.]
Complications of chronic kidney disease
Because CKD is a progressive disease, it can also lead to other complications, as mentioned above, including:
— Heart disease
— Excess calcium and potassium in the body
— Fluid buildup and swelling
— Anemia
These complications can be serious problems in themselves that need to be addressed.
How Kidney Disease Is Diagnosed
If your doctor suspects that you have any kind of kidney disease, you’ll undergo a number of tests, including:
— Urine test. This involves peeing in a cup and having the urine analyzed. One of the key indications that something is wrong with your kidneys is if there’s too much protein in your urine.
— Blood test. Your doctor will also likely order some lab work to look at your creatinine levels. Damage to the kidneys results in less ability to filter creatinine from the blood, so higher levels could signal a problem with the kidneys.
— Imaging tests. Your doctor might also order ultrasound or MRI imaging tests to get a better look at the structures inside your kidneys.
— Kidney biopsy. Not all conditions will require a kidney biopsy, but some, including glomerulonephritis and cancer of the kidney, will likely entail a biopsy so your doctor can get a better understanding of what’s happening with the cells in your kidneys.
Kidney Disease Treatment
With CKD, treatment depends on the underlying cause and the stage at which it was diagnosed. The stages range from 1 to 5, with 1 being the earliest stage and 5 being end-stage kidney disease.
There is no cure for CKD, and treatment usually aims to control symptoms, impede complications and slow progression of the disease.
Early-stage kidney disease treatment
Treatment of earlier-stage kidney disease typically focuses on:
— Reducing high blood pressure. Keeping your blood pressure under control can slow the progression of chronic kidney disease. “Blood pressure that is not well-controlled is one of the major reasons that kidney disease can progress to failure and dialysis and transplantation,” Rovin says. “By controlling that blood pressure, we can slow the progressive kidney disease down and preserve native function as long as possible.” This means not only taking any blood pressure medication your doctor prescribes, but also exercising more and reducing salt intake.
— Reducing cholesterol levels. Because high cholesterol can contribute to cardiovascular disease, controlling levels may slow the progression of kidney disease.
— Treating anemia. Low iron levels are a problem with some kidney disease patients, and boosting levels can help improve symptoms of fatigue and weakness that might develop alongside kidney disease.
— Reducing swelling. People with kidney disease have difficulty clearing excess fluid from the body, so diuretics that help move that fluid along may be prescribed.
— Protecting the bones. Calcium and vitamin D supplements can help reduce the risk of bone fractures that can arise because of kidney disease.
Chronic kidney disease treatment
Eventually, CKD may lead to late-stage kidney disease, also called end-stage kidney disease or renal failure. At this point, you’ll need more intensive interventions because your kidneys can no longer keep you alive on their own.
There are two treatment options:
Dialysis
Dialysis is a mechanical means of filtering the blood of wastes. It must be performed several times per week and often requires that patients spend several hours attached to a hemodialysis machine at an outpatient clinic, a dialysis center or at home.
Dialysis doesn’t entirely replace the function of the kidneys, but it’s a highly effective treatment method, particularly when combined with:
— Following your treatments on time as prescribed
— Following an approved dietary plan
— Being physically active
— Adhering to any medications
Patients undergoing dialysis require this treatment for the rest of their life or until they’re able to get a kidney transplant.
Kidney transplant
For some patients, a kidney transplant may be recommended. It involves replacing the diseased kidney or kidneys with organs from a healthy donor. It’s major surgery that can be difficult to organize because of the need for a genetic match from a suitable donor. A transplant also requires that the recipient stay on anti-rejection medications for the rest of their life to prevent the body from destroying the new organ.
Even with anti-rejection medications, organ transplant recipients always run the risk of developing an infection or rejecting the kidney.
[Related:Low Oxalate Diet: Can It Prevent Kidney Stones?]
How Long Can You Live With Kidney Disease?
The lifespan of someone with kidney disease depends on several factors, including the stage of the disease, any other underlying health conditions and how well their disease is managed. Those with advanced stages of kidney disease are more likely to experience complications.
According to the NKF, the average life expectancy for someone on dialysis is 5 to 10 years; however, many patients have lived well beyond 20 to 30 years. The NKF says a transplant from a living donor is expected to last about 15 to 20 years, whereas one from a deceased donor is expected to last about 8 to 12 years on average.
Kidney Disease Prevention
Preventing any disease before it starts is always the best option. You can reduce your chances of developing CKD by better managing other chronic health conditions that can contribute to the loss of kidney function, such as high blood pressure and diabetes.
In fact, Dr. Joseph A. Vassalotti, chief medical officer of the NKF and associate clinical professor of medicine in the division of nephrology at the Icahn School of Medicine at Mount Sinai in New York, says that avoiding kidney disease is one of the top reasons to manage diabetes and high blood pressure.
Strategies for kidney disease prevention include:
— Stop smoking. Because smoking can damage blood vessels and reduce kidney function, quitting helps lower your chances of developing kidney disease.
— Eat well. Opt for heart-healthy foods, including fruits, vegetables, whole grains and low-fat or fat-free dairy, and cut back on sugar and salt. The DASH diet has been linked with lowered blood pressure, so it is often recommended for those who are at risk of developing kidney disease or who already have it. You may also be advised to reduce your protein intake because the kidneys have to work harder to process the wastes that come from the breakdown of this macronutrient.
— Manage your weight. Maintaining a healthy weight reduces strain on your body, including organs like the kidneys, and reduces your risk for developing other health conditions that can lead to kidney disease, such as diabetes and hypertension.
— Stay active. Regularly staying active helps improve overall health.
— Get enough sleep. Poor-quality sleep can impact your overall health, which may increase inflammation in the body, affect kidney health and/or lead to other underlying health conditions over time.
— Limit alcohol intake. Excessive drinking can strain the kidneys. Stick to the national Dietary Guidelines for Americans, which recommends limiting intake to no more than one drink per day for women and no more than two for men.
— Stay well hydrated. Drinking enough water throughout the day helps your kidneys flush toxins; however, overhydration can also stress the kidneys, so make sure to strike a balance.
Health Care Providers That Treat Kidney Disease
Most people who have CKD or develop another kidney issue will likely start with their primary care physician. Depending on what’s going on, you may need to see a nephrologist, who specializes in diseases of the kidney. For certain kidney problems, a urologist –the doctor who looks after the urinary system — may also get involved.
“The thing I tell patients sometimes when they get confused about what a urologist does versus a nephrologist: A urologist is a surgeon, and a nephrologist is an internal medicine specialist. It’s analogous to a cardiologist and a cardiac surgeon,” Vassalotti says.
For example, if you have kidney cancer, you would see a urologist. If you need help managing a chronic kidney condition, you would see a nephrologist.
No matter whom you turn to for help, if you’re having symptoms that could be related to kidney disease, visit with your doctor sooner rather than later. Kidney failure is life threatening, but early intervention and management can make a big difference.
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A Patient’s Guide to Kidney Disease originally appeared on usnews.com
Update 12/10/24: This story was previously published at an earlier date and has been updated with new information.
