Your kidneys constantly filter your blood to remove waste products and control fluid levels. If these organs are damaged over an extended period — at least three months — you then have chronic kidney disease (CKD). CKD is progressive, meaning it becomes worse over time.

Whether your kidney disease is rare, like immunoglobulin A nephropathy (IgAN), or more common, the stages of kidney disease remain the same. This article covers how chronic kidney disease is staged and the symptoms you may experience with each of the five stages of CKD.

What Tests Help Assess Kidney Disease Stages?

The stage of kidney disease is based on how well the kidneys are working. Nephrologists (kidney doctors) use two main tests to measure kidney function and diagnose CKD — estimated glomerular filtration rate (eGFR) and urine albumin to creatinine ratio (uACR).

Blood and urine tests are used to diagnose chronic kidney disease. Imaging scans and a kidney biopsy may provide doctors with more detail about your condition.

A simple blood test is used to measure your eGFR, which shows your kidneys’ ability to filter your blood. An eGFR of 90 or above is normal.

The uACR test checks for any albumin (a type of protein) in your urine. Healthy kidneys can filter out water and waste while keeping protein in your body where it belongs. When protein leaks from your kidneys into your urine, it may be a sign of damage. A high uACR indicates that you’re more likely to develop CKD and, eventually, kidney failure. Together, uACR and eGFR help doctors stage CKD.

Imaging tests don’t help with staging, but they let your doctor take a closer look at your kidneys to explore kidney disease causes and structural problems that may be causing damage. Ultrasound uses sound waves that bounce off kidney tissues and form pictures. A CT scan uses X-rays at different angles to create 3D pictures. MRI also uses strong magnets and radio waves to make 3D images.

Your nephrologist may recommend a kidney biopsy — collecting a sample of tissue to be examined in the laboratory. This provides more information about what’s causing your CKD and exactly how much damage there is.

What Can You Expect With Each Stage of Kidney Disease?

As kidney function declines, you may experience additional and more severe symptoms.

Stage 1 Kidney Disease

In stage 1 CKD, your kidneys are damaged but still work well. According to the National Kidney Foundation, stage 1 CKD is defined by a normal eGFR. A diagnosis also requires signs of kidney damage, including a uACR of 30 or higher, persistent protein in your urine, or structural abnormalities seen on imaging tests. These findings must be present for at least three months.

Your kidneys can still filter out waste. You likely won’t notice symptoms at this early stage, which can make early detection tricky. Your doctor may catch signs of stage 1 CKD at an annual visit or while looking for other health conditions. Examples include high blood pressure or kidney damage that shows up on an imaging test given for another condition.

Stage 2 Kidney Disease

In stage 2 CKD, your kidneys have a harder time filtering your blood. Your eGFR will drop to between 60 and 89 as your kidney health declines, and your uACR will still be 30 or higher.

At early stages of CKD, you may notice urinary tract infections or swelling in your hands and feet. Some people don’t notice any symptoms until later stages.

For the most part, your kidneys continue to work well, and you still may not have any symptoms. Some people may notice swelling, though it’s uncommon this early in kidney disease and may be due to other conditions. If you notice new swelling, it’s a good idea to talk to your doctor.

Stage 3 Kidney Disease

If you have stage 3 CKD, your kidneys can no longer filter waste and fluid properly. Some people may notice symptoms that point to kidney damage, but many have none until later stages. Stage 3 CKD is divided into two substages based on kidney function and eGFR.

Stage 3A Kidney Disease

People with stage 3A CKD have an eGFR of 45 to 59 and mild to moderate kidney damage. At this point, your kidneys can still do some of their job but not as well as they used to. Your doctor will recommend treatments and lifestyle changes to stop your CKD from becoming worse. With the right treatment plan, you can prevent disease progression to the late stages of CKD.

Some people with stage 3A CKD may begin to experience symptoms. Your doctor will want to closely monitor your kidney function and work with you to manage risk factors that lead to further damage. That’s because your kidneys are no longer filtering waste products and fluid as effectively as they should. Symptoms of stage 3 CKD that may occur include:

• Fatigue and weakness
• Swelling in the hands and feet (from extra fluid)
• Muscle cramps
• Changes in how often you urinate
• Itchy skin
• Trouble sleeping, which may be due to restless legs syndrome (discomfort in the legs that makes it hard to stay still)

Stage 3B Kidney Disease

In stage 3B, you have moderate to severe kidney damage. Your eGFR drops to 30 to 44, meaning your kidneys are struggling to filter your blood properly. People with stage 3B CKD experience the same symptoms as those with stage 3A. It’s important to work closely with your doctor to stop your CKD from progressing to stage 4.

Stage 4 Kidney Disease

At stage 4, your kidneys are severely damaged, and your eGFR falls to between 15 and 29. Waste products continue building up in your bloodstream, causing more severe CKD symptoms and possibly leading to:

• Anemia (low red blood cell levels)
• High blood pressure
• Heart disease
• Metabolic acidosis (acid buildup in the blood)

At stage 4 CKD, you may experience nausea, vomiting, and appetite, as well as the fatigue, cramping, itching, and sleeping problems seen in stage 3.

The kidneys also help balance and remove extra minerals from the body. People with stage 4 CKD and severe kidney damage tend to have high phosphorus levels. Excess phosphorus in the blood can also pull calcium out of the bones and lead to bone disease. The extra calcium and phosphorus can then form hard deposits in organs like the heart, lungs, and blood vessels.

Stage 4 CKD causes symptoms similar to those of stage 3. You may also feel nauseous or throw up. Loss of kidney function can lead to reduced appetite over time. If you’re experiencing any of these symptoms, it may be a sign your CKD is progressing.

Stage 5 Kidney Disease

People with stage 5 CKD — also referred to as end-stage kidney disease or end-stage renal disease (ESRD) — have kidney failure and an eGFR of less than 15. The kidneys no longer work well enough to filter blood on their own.

Stage 5 CKD causes severe symptoms that can be life-threatening if left untreated. In addition to earlier-stage CKD symptoms, you may experience:

• Decreased urine output (though some people still make urine)
• Shortness of breath
• A yellow or gray hue to your skin
• Changes to your nails

Several conditions, like diabetes, high blood pressure, autoimmune conditions, and genetic kidney diseases, may eventually progress to kidney failure if not treated appropriately. If you’re living with a kidney disease like IgAN, you may be more likely to develop stage 5 CKD. Studies show that 20 percent to 40 percent of people with IgAN progress to kidney failure within 10 to 20 years of their diagnosis.

The only way to treat kidney failure or stage 5 CKD is with dialysis or a kidney transplant.

Dialysis, including hemodialysis and peritoneal dialysis, is a treatment that takes over the kidneys’ job of filtering waste and extra fluid from your blood. Some people may choose conservative management instead of starting dialysis. This is a personal decision to make with your healthcare team.

Kidney transplant is a surgery that replaces your damaged kidney with a functional kidney from a donor.

Your nephrologist will help you choose the best option based on your overall health and lifestyle. Regular checkups are crucial to manage your condition.

Join the Conversation

On myIgANteam, people share their experiences with immunoglobulin A nephropathy, get advice, and find support from others who understand.

What symptoms have you noticed with different stages of chronic kidney disease? Let others know in the comments below.