Learn about the different stages of kidney disease
There are five stages of CKD and different symptoms and treatments associated with each stage.
How to detect a CKD Stage ?
To assign a CKD stage, your doctor must determine how well your kidneys are working.
One way to do this is with a urine test to assess your albumin-creatinine ratio (ACR). It shows if protein is leaking into the urine (proteinuria), which is a sign of kidney damage.
ACR levels are staged as follows:
A1 | lower than 3mg/mmol, a normal to mild increase |
A2 | 3–30mg/mmol, a moderate increase |
A3 | higher than 30mg/mmol, a severe increase |
Your doctor may also order imaging tests, such as an ultrasound, to assess the structure of your kidneys.
A blood test measures creatinine, urea, and other waste products in the blood to see how well the kidneys work. This is called the estimated glomerular filtration rate (eGFR). A GFR of 100 mL/min is normal.
This table highlights the five stages of CKD. More information about each stage follows the table.
Stage | Description | GFR | Percent of kidney function |
1 | normal to highly functioning kidney | >90 mL/min | >90% |
2 | mild decrease in kidney function | 60–89 mL/min | 60–89% |
3A | mild-to-moderate decrease in kidney function | 45–59 mL/min | 45–59% |
3B | mild-to-moderate decrease in kidney function | 30–44 mL/min | 30–44% |
4 | severe decrease in kidney function | 15–29 mL/min | 15–29% |
5 | kidney failure | <15 mL/min | <15% |
In stage 1, there’s very mild damage to the kidneys. They’re quite adaptable and can adjust for this, allowing them to keep performing at 90 percent or better.
At this stage, CKD is likely to be discovered by chance during routine blood and urine tests. You may also have these tests if you have diabetes or high blood pressure, the top causes of CKD in the United States.
Typically, there are no symptoms when kidneys function at 90 percent or better.
You can slow disease progression by taking these steps:
If you don’t already see a kidney specialist (nephrologist), ask your general physician to refer you to one.
In stage 2, kidneys are functioning between 60 and 89 percent.
At this stage, you might still be symptom free. Or symptoms are nonspecific, such as:
It’s time to develop a relationship with a kidney specialist. There’s no cure for CKD, but early treatment can slow or stop progression.
It’s important to address the underlying cause. If you have diabetes, high blood pressure, or heart disease, follow your doctor’s instructions for managing these conditions.
It’s also important to maintain a good diet, get regular exercise, and manage your weight. If you smoke, ask your doctor about smoking cessation programs.
Stage 3A means your kidney is functioning between 45 and 59 percent. Stage 3B means kidney function is between 30 and 44 percent.
The kidneys aren’t filtering waste, toxins, and fluids well and these are starting to build up.
Not everyone has symptoms at stage 3. But you may have:
Complications may include:
It’s important to manage underlying conditions to help preserve kidney function. This may include:
You’ll probably need frequent follow-up visits and tests so adjustments can be made if necessary.
Your doctor can refer you to a dietitian to make sure you’re getting all the nutrients you need.
Stage 4 means you have moderate-to-severe kidney damage. They’re functioning between 15 and 29 percent, so you may be building up more waste, toxins, and fluids in your body.
It’s vital that you do all you can to prevent progression to kidney failure.
According to the CDC, 48 percentTrusted Source of people with severely reduced kidney function aren’t even aware they have it.
Symptoms can include:
Complications can include:
You’re also at increased risk of heart disease and stroke.
In stage 4, you’ll need to work very closely with your doctors. In addition to the same treatment as earlier stages, you should start discussions about dialysis and kidney transplant should your kidneys fail.
These procedures take careful organization and a lot of time, so it’s wise to have a plan in place now.
Stage 5 means your kidneys are working at less than 15 percent capacity or you have kidney failure.
When that happens, the buildup of waste and toxins becomes life-threatening. This is end-stage renal disease.
Symptoms of kidney failure can include:
The risk of heart disease and stroke is growing.
Once you have complete kidney failure, life expectancy is only a few months without dialysis or a kidney transplant.
Dialysis isn’t a cure for kidney disease, but a process to remove waste and fluid from your blood. There are two types of dialysis, hemodialysis and peritoneal dialysis.
Hemodialysis is done at a dialysis center on a set schedule, usually 3 times a week.
Before each treatment, two needles are placed in your arm. They’re attached to a dialyzer, which is sometimes referred to as an artificial kidney. Your blood is pumped through the filter and returned to your body.
You can be trained to do this at home, but it requires a surgical procedure to create vein access. Home dialysis is done more frequently than dialysis in a treatment center.
For peritoneal dialysis, you’ll have a catheter surgically placed into your abdomen.
During treatment, dialysis solution flows through the catheter into the abdomen, after which you can go about your normal day. A few hours later, you can drain the catheter into a bag and discard it. This must be repeated 4 to 6 times a day.
A kidney transplant involves replacing your kidney with a healthy one. Kidneys can come from living or deceased donors. You won’t need dialysis, but you’ll have to take anti-rejection drugs for the rest of your life.