Diabetic nephropathy is a type of progressive kidney disease that may occur in people who have diabetes. It affects people with type 1 and type 2 diabetes, and risk increases with the duration of the disease and other risk factors like high blood pressure and a family history of kidney disease.
Over 40 percent of cases of kidney failure are caused by diabetes, and it’s estimated that approximately 180,000 people are living with kidney failure caused by complications of diabetes. Diabetes is also the most common cause of end-stage renal disease (ESRD). ESRD is the fifth and final stage of diabetic nephropathy.
Diabetic nephropathy progresses slowly. With early treatment, you can slow or even stop the progression of the disease. Not everyone who develops diabetic nephropathy will progress to kidney failure or ESRD, and having diabetes does not mean you will develop diabetic nephropathy.
Causes of diabetic nephropathy:
Each of your kidneys has about one million nephrons. Nephrons are small structures that filter waste from your blood. Diabetes can cause the nephrons to thicken and scar, which make them less able to filter waste and remove fluid from the body. This causes them to leak a type of protein called albumin into your urine. Albumin can be measured to help diagnose and determine the progression of diabetic nephropathy.
The exact reason this occurs in people with diabetes is unknown, but high blood sugar levels and high blood pressure are thought to contribute to diabetic nephropathy. Persistently high blood sugar or blood pressure levels are two things that can damage your kidneys, making them unable to filter waste and remove water from your body.
Other factors have been shown to increase your risk of getting diabetic nephropathy, such as:
- Being African-American, Hispanic, or American Indian.
- Having a family history of kidney disease.
- Developing type 1 diabetes before you are 20 years of age.
- Being overweight or obese.
- Having other diabetes complications, such as eye disease or nerve damage.
Diabetic nephropathy is a common complication of diabetes, types 1 and 2.
Over time the high blood sugar associated with untreated diabetes causes high blood pressure. This in turn damages the kidneys by increasing the
pressure in the delicate filtering system of the kidneys.
Several factors may increase your risk of diabetic nephropathy, including:
- Diabetes, type 1 or 2.
- High blood sugar (hyperglycemia) that’s difficult to control.
- High blood pressure (hypertension) that’s difficult to control.
- Being a smoker and having diabetes.
- High blood cholesterol and having diabetes.
- A family history of diabetes and kidney disease.
Symptoms of diabetic nephropathy:
The early stages of kidney damage often do not cause noticeable symptoms. You may not experience any symptoms until you are in the late stages of chronic kidney disease.
Worsening blood pressure control.
Protein in the urine.
Swelling of feet, ankles, hands or eyes.
Increased need to urinate.
- Less need for insulin or diabetes medicine.
- Confusion or difficulty concentrating.
- Loss of appetite.
- Nausea and vomiting.
- Persistent itching.
How is diabetic nephropathy diagnosed?
If you have diabetes, your doctor will mostly likely perform yearly blood and urine tests on you to check for early signs of kidney damage. That is because diabetes is a risk factor for kidney damage. Common tests include:
Microalbuminuria urine test:
A microalbuminuria urine test checks for albumin in your urine. Normal urine does not contain albumin, so the presence of the protein in your urine is a sign of kidney damage.
BUN blood test:
A BUN blood test checks for the presence of urea nitrogen in your blood. Urea nitrogen forms when protein is broken down. Higher than normal levels of urea nitrogen in your blood may be a sign of kidney failure.
Serum creatinine blood test:
A serum creatinine blood test measures creatinine levels in your blood. Your kidneys remove creatinine from your body by sending creatinine to the bladder, where it is released with urine. If your kidneys are damaged, they cannot remove the creatinine properly from your blood.
High creatinine levels in your blood may mean that your kidneys are not functioning correctly. Your doctor will use your creatinine level to estimate your glomerular filtration rate (eGFR), which helps to determine how well your kidneys are working.
If your doctor suspects that you have diabetic nephropathy, they may order a kidney biopsy. A kidney biopsy is a surgical procedure in which a small sample of one or both of your kidneys is removed, so it can be viewed under a microscope.
Stages of kidney disease:
Early treatment can help slow down the progression of kidney disease. There are five stages of kidney disease.
Stage 1 is the mildest stage and kidney functionality can be restored with treatment. Stage 5 is the most severe form of kidney failure. At stage 5, the kidney is no longer functional, and you will need to have dialysis or a kidney transplant.
Your glomerular filtration rate (GFR) can be used to help your doctor determine the stage of your kidney disease. Knowing your stage is important because that will affect your treatment plan. To calculate your GFR, your doctor will use the results from a creatinine blood test along with your age, gender, and physique.
|Stage||GFR||Damage and functionality|
|stage-1||90+||mildest stage; kidneys have some damage, but are still functioning at a normal level|
| kidneys are damaged and have some loss of functionality
kidney has lost up to half of its functionality; can also lead to problems with your bones
severe kidney damage
kidney failure; you will need dialysis or a kidney transplant
There is no cure for diabetic nephropathy, but treatments can delay or stop the progression of the disease. Treatments consist of keeping blood sugar levels under control and blood pressure levels within their target range through medications and lifestyle changes. Your doctor will also recommend special diet modifications. If your kidney disease progresses to ESRD, you will require more invasive treatments.
Medications:Regularly monitoring your blood sugar levels, using proper dosages of insulin, and taking medications as directed by your doctor can keep your blood sugar levels under control. Your doctor may prescribe ACE inhibitors, angiotensin receptor blockers (ARBs), or other blood pressure medications to keep your blood pressure levels down.
If you have ESRD, you will likely need dialysis or a kidney transplant, in addition to treatments for earlier stages of kidney disease.
Dialysis is a procedure that helps to filter the waste out of your blood. There are two main types of dialysis: hemodialysis and peritoneal dialysis. Your doctor will help you decide which is best for you.The other option for treatment is a kidney transplant. For a kidney transplant, a kidney from a donor will be placed into your body. The success of dialysis and kidney transplants differs with each person.
Diet and lifestyle changes:
Your doctor or dietitian will help you plan a special diet that is easy on your kidneys. These diets are more restrictive than a standard diet for people with diabetes. Your doctor may recommend:
- limiting protein intake
- consuming healthy fats, but limiting consumption of oils and saturated fatty acids
- reducing sodium intake to 1,500 to 2,000 mg/dL or less
- limiting potassium consumption, which could include reducing or restricting your intake of high potassium foods like bananas, avocados, and spinach
- limiting consumption of foods high in phosphorus, such as yogurt, milk, and processed meats
Your doctor can help you develop a customized diet plan. You can also work with a dietitian to help you better understand how to best balance the foods you eat.
Complications of diabetic nephropathy may develop gradually over months or years. They may include:
- Fluid retention, which could lead to swelling in your arms and legs, high blood pressure, or fluid in your lungs (pulmonary edema).
- Heart and blood vessel disease (cardiovascular disease), possibly leading to stroke.
- Damage to the blood vessels of the retina (diabetic retinopathy).
- Foot sores, erectile dysfunction, diarrhea and other problems related to damaged nerves and blood vessels.
- Pregnancy complications that carry risks for the mother and the developing fetus.
- Irreversible damage to your kidneys (end-stage kidney disease), eventually requiring either dialysis or a kidney transplant for survival.
To reduce your risk of developing diabetic kidney disease:
- Treat your diabetes. With effective treatment of diabetes, you may prevent or delay diabetic kidney disease.
- Manage high blood pressure or other medical conditions. If you have high blood pressure or other conditions that increase your risk of kidney disease, work with your doctor to control them. Ask your doctor about tests to look for signs of kidney damage.
- Follow instructions on over-the-counter medications. When using nonprescription pain relievers, such as aspirin, ibuprofen (Advil, Motrin IB, others) and acetaminophen (Tylenol, others), follow the instructions on the package. For people with diabetic kidney disease, taking these types of pain relievers can lead to kidney damage.
- Maintain a healthy weight. If you’re at a healthy weight, work to maintain it by being physically active most days of the week. If you need to lose weight, talk with your doctor about strategies for weight loss.Often this involves increasing daily physical activity and reducing calories.
Don’t smoke. Cigarette smoking can damage your kidneys and make existing kidney damage worse. If you’re a smoker, talk to your doctor about strategies for quitting smoking. Support groups, counseling and medications can all help you to stop.