What causes stage 2 kidney disease

Diabetes and high blood pressure are the most common causes of chronic kidney disease (CKD). Your health care provider will look at your health history and may do tests to find out why you have kidney disease. The cause of your kidney disease may affect the type of treatment you receive.

Diabetes

Too much glucose, also called sugar, in your blood damages your kidneys’ filters. Over time, your kidneys can become so damaged that they no longer do a good job filtering wastes and extra fluid from your blood.

Often, the first sign of kidney disease from diabetes is protein in your urine. When the filters are damaged, a protein called albumin, which you need to stay healthy, passes out of your blood and into your urine. A healthy kidney doesn’t let albumin pass from the blood into the urine.

Diabetic kidney disease is the medical term for kidney disease caused by diabetes.

High blood pressure

High blood pressure can damage blood vessels in the kidneys so they don’t work as well. If the blood vessels in your kidneys are damaged, your kidneys may not work as well to remove wastes and extra fluid from your body. Extra fluid in the blood vessels may then raise blood pressure even more, creating a dangerous cycle.

More information is provided in the NIDDK health topic, High Blood Pressure and Kidney Disease.

Other causes of kidney disease

Other causes of kidney disease include

A person with stage 2 chronic kidney disease (CKD) has kidney damage with a mild decrease in their glomerular filtration rate (GFR) of 60-89 ml/min. There are usually no symptoms to indicate the kidneys are damaged. Because kidneys do a good job even when they’re not functioning at 100 percent, most people will not know they have stage 2 CKD. If they do find out they’re in stage 2, it’s usually because they were being tested for another condition such as diabetes or high blood pressure–the two leading causes of kidney disease.

Signs of stage 2 kidney disease

Other ways a person may discover they are in stage 2 CKD include:

• Higher than normal levels of creatinine or urea in the blood
• Blood or protein in the urine
• Evidence of kidney damage in an MRI, CT scan, ultrasound or contrast X-ray
• A family history of polycystic kidney disease (PKD)

Treating stage 2 kidney disease

Regular testing for protein in the urine and serum creatinine can show whether the kidney damage is progressing. Living a healthy lifestyle can help slow progression of kidney disease. It’s recommended that people in stage 2 CKD:

1. Eat a healthy diet
   • Include a variety of grains (especially whole grains), fresh fruits and vegetables.
   • Change to a diet that is low in saturated fat and cholesterol and moderate in total fats.
   • Limit intake of refined and processed foods high in sugar and sodium.
   • Choose and prepare foods with less salt or high-sodium ingredients.
   • Aim for a healthy weight, consume adequate calories and include physical activity each day.
   • Keep protein intake within  a healthy level, as recommended by a renal dietitian.
   • Consume vitamins and minerals as recommended by a doctor.
   • Potassium and phosphorus are usually not restricted unless blood levels are above normal
2. Keep their blood pressure at a healthy level.
   • 125/75 for those with diabetes
   • 130/85 for non-diabetes and non-proteinuria
   • 125/75 for non-diabetes with proteinuria
3. Keep their blood sugar or diabetes under control.
4. Have regular checkups with their doctor and include a serum creatinine test to measure GFR.
5. Take medicines as prescribed by their doctor.
6. Exercise regularly.
7. Stop smoking.

Living with stage 2 kidney disease

There is no cure for kidney disease, but it may be possible to stop its progress or at least slow down the damage. In many cases, the correct treatment and lifestyle changes can help keep a person and their kidneys healthier longer.

Many people do not experience symptoms of kidney disease until the later stages of CKD. Possible stage 2 kidney disease symptoms and signs include:

• High blood pressure
• Swelling in your legs
• Urinary tract infections
• Abnormal urine test (protein in urine)

Learn what the stages of chronic kidney disease (CKD) refer to and how stages are based on the eGFR test. Get an overview of each of the five stages.

Chronic kidney disease (CKD) is divided into five stages. The stages are based on the eGFR test result and how well your kidneys work to filter waste and extra fluid out of your blood. As the stages go up, kidney disease gets worse and your kidneys work less well. At each stage, it is important to take steps to slow down the damage to your kidneys.

What do the stages of chronic kidney disease (CKD) refer to?

The five stages of CKD refer to how well your kidneys are working. Kidney disease can get worse in time. In the early stages (Stages 1–3), your kidneys are still able to filter waste out of your blood. In the later stages (Stages 4–5), your kidneys must work harder to filter your blood and may stop working altogether.

The goal at each stage of CKD is to take steps to slow down the damage to your kidneys and keep your kidneys working as long as possible.

To find out your stage of CKD, doctors will do tests, such as:

• eGFR tests (blood tests), which is a measure of how well your kidneys are working

Please note: eGFR is an estimate of how well your kidneys are working. The way eGFR is calculated will be changing. Currently the test considers your age, sex and race, among other things. A task force led by the National Kidney Foundation (NKF) and the American Society of Nephrology (ASN) is working on recommendations that may remove Black race as a factor in the eGFR calculation. The task force has been seeking the input of kidney disease experts to come up with the best way to make the eGFR test as accurate as possible. The American Kidney Fund (AKF) advised the task force to remove race from the eGFR so there is no bias in testing kidney function. This would help to make sure that every person will receive health care that is fair and of the highest quality. When the NKF-ASN task force makes its recommendations, AKF will promptly review them and then update our educational materials.

 

Each stage is based on the eGFR number and has different symptoms and treatments.

1. 

   Stage 1 CKD means you have a normal eGFR of 90 or greater and mild damage to your kidneys. Your kidneys are still working well, so you may not have any symptoms. You may have other signs of kidney damage, such as protein in your urine.

2. 

   Stage 2 CKD means your eGFR has gone down to between 60 and 89, and you have mild damage to your kidneys. Most of the time, your kidneys are still working well, so you may not have any symptoms. You may have other signs of kidney damage, such as protein in your urine or physical damage. 

3. 

   Stage 3 CKD means you have an eGFR between 30 and 59 and mild to moderate damage to your kidneys. Your kidneys do not work as well as they should to filter waste and extra fluid out of your blood. This waste can build up in your body and begin to cause other health problems, such as high blood pressure and bone disease. You may begin to have symptoms, such as feeling weak and tired or swelling in your hands or feet. 

   Stage 3 CKD is split into two substages based on your eGFR:

   • Stage 3a means you have an eFGR between 45 and 59
   • Stage 3b means you have an eGFR between 30 and 44

   With treatment and healthy life changes, many people in Stage 3 do not move to Stage 4 or Stage 5.

4. 

   Stage 4 CKD means you have an eGFR between 15 and 29 and moderate to severe damage to your kidneys. Your kidneys do not work as well as they should to filter waste out of your blood. This waste can build up in your body and cause other health problems, such as high blood pressure, bone disease and heart disease. You will likely have symptoms such as swelling of your hands and feet and pain in your lower back. 

   This is the last stage before kidney failure. It is important to have regular visits with a nephrologist (kidney doctor) to take steps to slow kidney damage and plan ahead for possible treatments for kidney failure.

5. 

   Stage 5 CKD means you have an eGFR less than 15 and severe damage to your kidneys. Your kidneys are getting very close to failure or have already failed (stopped working). Because your kidneys have stopped working to filter waste out of your blood, waste products build up in your body, which can make you very sick and cause other health problems. When your kidneys fail, treatment options to survive include dialysis or a kidney transplant.