Diabetic Nephropathy (Diabetic Kidney Disease): Symptoms, Causes, Diagnosis & Treatment — Complete Guide

Medically reviewed by Dr. Baraa Alnahhal, MD · Last reviewed: October 2026

Quick Answer: What Is Diabetic Nephropathy?

Diabetic nephropathy, or diabetic kidney disease, is a serious complication of type 1 and type 2 diabetes in which high blood sugar slowly damages the kidneys' filters. About 1 in 3 people with diabetes in the United States develop it, often without early symptoms, so yearly screening matters. Controlling blood sugar and blood pressure can prevent or slow it.

What the research says

• Kidney damage can begin in youth, so screening matters at every age. A systematic review and meta-analysis of 57 studies (51,819 children and adolescents with diabetes) found a pooled nephropathy prevalence of 13.70% (95% CI 10.25–17.54) in type 1 and 12.63% (95% CI 7.99–18.07) in type 2 diabetes, concluding that routine screening and early intervention are essential regardless of diabetes type. (Ezzatvar et al., Pediatr Diabetes, 2025) [3]

• Three newer drug classes each lower the risk of kidney events. A Bayesian network meta-analysis of six trial datasets (20,521 people with type 2 diabetes and chronic kidney disease) found hazard ratios for kidney outcomes versus placebo of 0.70 (95% credible interval 0.64–0.76) for SGLT2 inhibitors, 0.76 (0.66–0.88) for semaglutide, and 0.84 (0.77–0.92) for finerenone; all three also reduced cardiovascular risk. (He et al., Front Pharmacol, 2026) [4]

• Benefits come with trade-offs worth knowing. An umbrella review of 12 systematic reviews reported that SGLT2 inhibitors lowered kidney disease progression (risk ratio 0.63, 95% CI 0.58–0.69) but increased genital infections (risk ratio 3.30, 95% CI 2.74–3.99); the authors noted that all included reviews had critically low confidence ratings. (Eisa and Khoury, J Diabetes Metab Disord, 2026) [5]

• SGLT2 inhibitors lower the risk of kidney failure in type 2 diabetes. A meta-analysis of four trials with 38,723 people with type 2 diabetes found that SGLT2 inhibitors reduced the risk of dialysis, transplantation, or death from kidney disease (relative risk 0.67; 95% CI 0.52–0.86) and reduced acute kidney injury (relative risk 0.75), with benefit across levels of kidney function. (Neuen et al., Lancet Diabetes Endocrinol, 2019) [8]

• SGLT2 inhibitors and GLP-1 agonists both lower kidney failure risk, with different side effects. A network meta-analysis of 764 trials (421,346 adults with type 2 diabetes) found that both drug classes lowered the risk of kidney failure (high-certainty evidence); SGLT2 inhibitors caused genital infections, while GLP-1 receptor agonists might cause severe gastrointestinal events (low-certainty evidence). (Palmer et al., BMJ, 2021) [9]

• People who already have kidney disease still benefit. In 27 studies of people with both type 2 diabetes and chronic kidney disease (up to 7,363 participants), SGLT2 inhibitors reduced the risk of a composite kidney outcome (hazard ratio 0.71; 95% CI 0.53–0.95), slowed the yearly decline in eGFR by about 1.35 mL/min/1.73 m², and lowered albuminuria. (Toyama et al., Diabetes Obes Metab, 2019) [10]

Diabetic Nephropathy at a Glance

What Is Diabetic Nephropathy?

Your kidneys have an essential job: they clean the blood. As blood moves through the body, it picks up extra fluid, chemicals, and waste. The kidneys separate this material from the blood and carry it out of the body in urine. When the kidneys can no longer do this job, serious health problems follow.

Diabetic nephropathy — also called diabetic kidney disease — is a serious complication of both type 1 and type 2 diabetes. In the United States, roughly 1 in 3 people living with diabetes has this condition. Over years, it slowly damages the kidneys' filtering system.

Diabetic nephropathy is the most common cause of kidney failure in the world. [6] Between 2 and 4 out of every 10 people with diabetes may develop it. [6]

The encouraging news: the best way to prevent or delay diabetic nephropathy is within reach — a healthy lifestyle, and keeping diabetes and high blood pressure managed. Early treatment may prevent the condition, slow it, and lower the chance of complications.

How the Kidneys Filter Your Blood

Understanding the problem starts with understanding how a healthy kidney works.

Each kidney contains about 1 million tiny filtering units called glomeruli (singular: glomerulus). Every filter is made of tiny blood vessels called capillaries. As blood flows into a glomerulus, small molecules — water, minerals, nutrients, and waste — pass through the capillary walls. Large molecules, such as proteins and red blood cells, stay in the blood where they belong.

The filtered molecules then pass into a tube called a tubule. Here, the water, nutrients, and minerals the body needs are sent back into the bloodstream. What remains — extra water and waste — becomes urine, which flows to the bladder and leaves the body.

The kidneys' tiny filters (glomeruli) keep protein in the blood. Diabetes and high blood pressure scar these filters, letting protein leak into the urine. Source: rinnit.com

Signs and Symptoms

Early Stages: Often No Warning Signs

Here is the most important thing to know about diabetic nephropathy: in the early stages, there might not be symptoms at all. The damage develops silently over years. This is exactly why people with diabetes should never wait for symptoms before getting screened.

The earliest sign is usually protein in the urine (proteinuria), which you cannot see or feel and which shows up only on a urine test (urinalysis). [6]

Later-Stage Symptoms

In later stages, damaged kidneys begin to show signs. Symptoms may include:

Other symptoms can include dry skin, muscle cramps, excessive hiccups, a metallic taste in the mouth and needing less insulin than usual. [6]

When to see a doctor: Make an appointment if you have symptoms of kidney disease. If you have diabetes, visit your healthcare professional yearly — or as often as you're told — for tests that measure how well your kidneys are working.

Causes: How Diabetes Damages the Kidneys

Diabetic nephropathy happens when diabetes damages blood vessels and other cells in the kidneys.

Over time, diabetes that is not well controlled damages the blood vessels in the kidneys that filter waste from the blood. This causes kidney damage — and the kidney damage, in turn, can cause high blood pressure.

Then a harmful cycle takes over: high blood pressure raises the pressure inside the kidneys' filtering system, which causes more kidney damage. Both conditions feed each other, which is why controlling both matters so much.

Both type 1 and type 2 diabetes can cause diabetic nephropathy, and type 2 is the more common cause. [6] It takes years for diabetes to damage the kidneys: most people with type 1 diabetes have some kidney damage within two to five years of diagnosis, and about 3 or 4 out of 10 progress to a more severe stage within 10 to 30 years. [6] Type 2 diabetes is thought to take a similar amount of time, but because it often goes unnoticed for years, kidney damage may be found soon after diagnosis. [6]

The complete picture of diabetic kidney disease, from warning signs to screening and treatment. Source: rinnit.com

Risk Factors

If you have diabetes, the following factors raise your risk of diabetic nephropathy:

The risk is also higher for people who are Black, Native American, Alaska Native, First Nations, Polynesian or Maori. [6]

Complications

Complications of diabetic nephropathy build up slowly over months or years. They may include:

Diabetes can also affect the urinary tract and sexual function: it can make urination more frequent and cause incontinence, and in rarer cases it dulls the nerves so that the bladder does not sense it is filling, which can overstretch the bladder until it stops working. [7] It can also affect the nerves that coordinate sexual response, reducing erectile function in men and causing problems with lubrication and orgasm in women. [7]

Prevention: Six Habits That Protect Your Kidneys

You can lower your risk of developing diabetic nephropathy:

1. See your health care team regularly. Keep appointments that check how well you are managing your diabetes and screen for kidney disease and other complications — yearly or more often.

2. Treat your diabetes. With good treatment, you can keep blood sugar in the target range as much as possible. This may prevent or slow diabetic nephropathy.

3. Manage high blood pressure or other conditions that raise your kidney disease risk.

4. Take over-the-counter medicines only as directed. Read the labels on pain relievers. Aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs) — such as naproxen sodium (Aleve) and ibuprofen (Advil, Motrin IB) — can lead to kidney damage in people with diabetic nephropathy.

5. Stay at a healthy weight. Be physically active most days of the week, or talk with your team about the best way to lose weight.

6. Don't smoke. If you smoke, ask your team about ways to quit — support groups, counseling, and some medicines can help.

For readers who want a fuller picture of diabetes management, our complete diabetes guide covers the parent topic in depth.

How Diabetic Nephropathy Is Diagnosed

Diabetic nephropathy is usually found during the regular testing that is part of managing diabetes — not because symptoms appeared. [2]

Who should get tested: Get tested every year if you have type 2 diabetes, or if you have had type 1 diabetes for more than five years.

Appointments to monitor kidney health are typically every three to six months, or as your provider recommends. [6]

Routine Screening Tests

Healthcare providers stage diabetic nephropathy using the estimated glomerular filtration rate (eGFR), a calculation from a blood test that shows how well the kidneys filter blood. [6] A normal eGFR ranges from 60 to over 100, and an eGFR of 0 means the kidneys are not working at all. [6] The five stages are: [6]

• Stage I (eGFR 90 or higher): mild kidney damage, but the kidneys still function normally.

• Stage II (eGFR 60 to 89): more damage than stage I, but the kidneys still function well.

• Stage III (eGFR 30 to 59): mild or moderate loss of kidney function.

• Stage IV (eGFR 15 to 29): moderate to severe loss of kidney function.

• Stage V (eGFR below 15): the kidneys are nearing or at complete failure.

Other Diagnostic Tests

• Imaging tests. X-rays and ultrasound show the makeup and size of the kidneys. CT and MRI scans show how well blood is moving within the kidneys.

• Kidney biopsy. A healthcare professional uses a needle — guided by imaging such as ultrasound and numbed with local anesthetic — to remove small pieces of kidney tissue for lab study.

Sometimes urine or blood tests alone are enough for a diagnosis; if the diagnosis is unclear, imaging of the kidneys and blood vessels or a kidney biopsy may be needed. [6]

Treatment

The first step in treating diabetic nephropathy is to treat and control diabetes and high blood pressure. Treatment includes diet, lifestyle changes, exercise, and prescription medicines. Controlling blood sugar and blood pressure might prevent or delay kidney problems and other complications. [2]

Kidney damage from diabetes cannot be reversed, but early diagnosis and following the treatment plan can slow or even stop its progression. [6] Without treatment it can advance to kidney failure, which may be fatal. [6]

Medicines for Early Stages

If you take these medicines, you will need regular follow-up testing to see whether your kidney disease is stable or getting worse.

Treatment for Advanced (End-Stage) Kidney Disease

When kidney failure — also called end-stage kidney disease — develops, treatment focuses on either replacing the work of your kidneys or keeping you comfortable:

• Kidney dialysis removes waste products and extra fluid from the blood. Hemodialysis filters blood outside the body using a machine that does the work of the kidneys; you might visit a dialysis center about three times a week (each session takes 3 to 5 hours), or have dialysis done at home with a trained caregiver. Peritoneal dialysis uses the inner lining of the abdomen (the peritoneum) to filter waste; a cleansing fluid flows through a tube to the peritoneum, and it can be done at home or at work, though not everyone can use this method.

• Transplant. A kidney transplant — or a combined kidney-pancreas transplant — is sometimes the best choice. You will be assessed to find out whether you can have the surgery. The transplant kidney is placed in the lower abdomen, its vessels connect to vessels just above one leg, and its ureter connects to the bladder; your own kidneys usually stay in place. Surgery takes about 3 to 4 hours.

• Symptom management. If you have kidney failure and do not want dialysis or a transplant, you would likely live only a few months; treatment can help keep you comfortable.

Researchers are also studying regenerative medicine techniques — such as pancreas islet cell transplant or stem cell therapy — that might one day reverse or slow kidney damage. These are still under study.

Lifestyle and Home Care

Diet, exercise, and self-care are essential to control blood sugar and blood pressure:

1. Monitor your blood sugar. Check as often as your team advises — for example, once a day and before or after exercise, or several times a day if you take insulin.

2. Be active most days. Aim for at least 30 minutes of moderate to vigorous aerobic exercise most days — 150 minutes a week total. Try brisk walking, swimming, biking, or running.

3. Eat a healthy diet. Choose high-fiber foods — fruits, nonstarchy vegetables, whole grains, and legumes. Limit saturated fats, processed meats, sweets, and salt.

4. Quit smoking.

5. Stay at a healthy weight. For some people, weight-loss surgery is an option.

6. Take a daily aspirin. Ask your doctor whether a daily low-dose aspirin makes sense to lower heart disease risk.

7. Talk to your health care team. Make sure every healthcare professional knows you have diabetic nephropathy. They can protect your kidneys by avoiding medical tests that use contrast dye — such as angiograms and CT scans — when possible.

Coping and Support

Living with diabetic nephropathy can be stressful. Three steps help:

• Connect with others who have diabetes and kidney disease. Ask about local support groups, or contact organizations such as the American Association of Kidney Patients or the National Kidney Foundation.

• Stick to your usual routine when possible. Keep doing the activities you enjoy and keep working, if your condition allows — this helps you cope with feelings of sadness or loss after diagnosis.

• Talk with someone you trust. A friend, family member, faith leader, or a social worker or counselor your team can recommend.

Preparing for Your Appointment

Diabetic nephropathy is most often found during regular appointments for diabetes care.

If You Were Recently Diagnosed

• How well are my kidneys working now?

• How can I keep my condition from getting worse?

• What treatments do you suggest, and how do they fit into my diabetes treatment plan?

• How will we know if these treatments are working?

At Ongoing Appointments

Review regularly: how often to check blood sugar and your target range; diet changes for blood sugar, cholesterol, or blood pressure; when to take medicines and whether with food; how diabetes management affects treatment of your other conditions; when to follow up; what should prompt a call or emergency care; and help paying for diabetes supplies. (Before any appointment, ask whether you need restrictions such as fasting.)

What Your Doctor Will Likely Ask You

• Do you understand your treatment plan?

• How are you coping with diabetes?

• Have you had low blood sugar?

• Do you know what to do if your blood sugar is too low or too high?

• What do you eat in a day?

• Are you exercising?

• What is hardest about managing your diabetes?

Frequently Asked Questions (FAQ)

What is diabetic nephropathy?

Diabetic nephropathy, also called diabetic kidney disease, is a serious complication of type 1 and type 2 diabetes in which high blood sugar slowly damages the kidneys' filtering system. In the United States, about 1 in 3 people living with diabetes has this condition.

Can diabetic nephropathy cause kidney failure?

Yes. Diabetic kidney disease can lead to kidney failure, also called end-stage kidney disease, which is life-threatening. When it does, treatment options are dialysis or a kidney transplant.

What are the symptoms of diabetic nephropathy?

Early stages often have no symptoms at all. In later stages, symptoms may include foamy urine, swelling of the feet, ankles, hands, or eyes, high blood pressure that gets harder to control, shortness of breath, tiredness, nausea, and itching.

Why does diabetes damage the kidneys?

Uncontrolled diabetes over time damages the blood vessels in the kidneys that filter waste from the blood. This causes high blood pressure, which then raises the pressure inside the filtering system and causes more kidney damage — a cycle that feeds itself.

How is diabetic nephropathy diagnosed?

Diabetic nephropathy is usually found during regular diabetes testing: yearly screening with a urinary albumin test, an albumin/creatinine ratio test, and a GFR blood test that measures how quickly the kidneys filter blood. Imaging tests or a kidney biopsy may also be used.

What medicines treat diabetic nephropathy?

The first step is controlling diabetes and blood pressure. Doctors may prescribe ACE inhibitors or ARBs for blood pressure, insulin or newer drugs such as GLP-1 receptor agonists and SGLT2 inhibitors for blood sugar, statins for cholesterol, and finerenone to reduce kidney scarring.

How can I protect my kidneys if I have diabetes?

Control your blood sugar and blood pressure, get screened yearly, follow a high-fiber healthy diet, exercise about 150 minutes a week, maintain a healthy weight, don't smoke, and take over-the-counter pain relievers such as ibuprofen and naproxen only as directed, since they can harm damaged kidneys.

Conclusion

The most important lessons from this guide come down to three points: diabetic nephropathy is common but preventable — about 1 in 3 people with diabetes develop it, and controlling blood sugar and blood pressure can prevent or slow it; early stages are silent — yearly screening tests (urine albumin, albumin/creatinine ratio, and GFR) catch the damage before symptoms appear; and treatment works when started early — modern medicines protect the kidneys, and even advanced disease can be managed with dialysis or transplant.

This complete guide has walked you through what diabetic nephropathy is, how diabetes damages the kidneys, what to watch for, how screening works, and every step of treatment — from daily habits to dialysis. Keep it as your reference for protecting your kidneys at every stage.

What to do next: If you have diabetes, understanding the whole condition helps you protect every part of your body — including your kidneys. Continue to our complete diabetes guide for the bigger picture of managing blood sugar.

This content is provided for general informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of a qualified healthcare provider with any questions about a medical condition.

Related Reading

Kidney-Pancreas Transplant: Who Qualifies, Surgery, Recovery and Outcomes

Learn more in our guide to Kidney Donation: Eligibility, Surgery, Risks and Recovery for Living Donors.

Urine Albumin-Creatinine Ratio (uACR): What the Test Shows and What Your Numbers Mean explains the urine test used to detect and monitor kidney damage.

Creatinine Clearance Test: 24-Hour Urine Collection, Purpose and Results explains the 24-hour urine and blood test used to check kidney function.

Learn more in our guide to Urine Protein Test: Normal Range, How It's Done and What High Protein Means.

Urine Protein Creatinine Ratio (UPCR): Test, Normal Range and Results explains the one-sample urine test used to measure protein loss from the kidneys.

Kidney Function Tests: Types, Normal eGFR by Age and What Results Mean explains eGFR, uACR and the other tests that check how well your kidneys work.

eGFR (Estimated Glomerular Filtration Rate): Normal Values, CKD Stages and What Results Mean explains the eGFR number used to measure kidney function and stage CKD.

References

1. Mayo Clinic Staff. Diabetic nephropathy (kidney disease) - Symptoms and causes. Mayo Clinic. October 24, 2023. https://www.mayoclinic.org/diseases-conditions/diabetic-nephropathy/symptoms-causes/syc-20354556

2. Mayo Clinic Staff. Diabetic nephropathy (kidney disease) - Diagnosis and treatment. Mayo Clinic. October 24, 2023. https://www.mayoclinic.org/diseases-conditions/diabetic-nephropathy/diagnosis-treatment/drc-20354562

3. Ezzatvar Y, et al. Global Prevalence of Microvascular Complications in Children and Adolescents With Type 1 and Type 2 Diabetes: A Systematic Review and Meta-Analysis. Pediatr Diabetes. 2025;2025:8398194. PMID 41346657. https://doi.org/10.1155/pedi/8398194

4. He Z, et al. SGLT2 inhibitors, semaglutide, and finerenone in diabetic kidney disease: a Bayesian network meta-analysis. Front Pharmacol. 2026;17:1882227. PMID 42851802. https://doi.org/10.3389/fphar.2026.1882227

5. Eisa N, et al. Multisystem effects of sodium-glucose cotransporter-2 inhibitors beyond glycaemic control: an umbrella review of systematic reviews and meta-analyses. J Diabetes Metab Disord. 2026;25(2):283. PMID 42856812. https://doi.org/10.1007/s40200-026-02097-x

6. Cleveland Clinic. Diabetes-Related Nephropathy: Symptoms & Treatment. Cleveland Clinic. Last updated January 5, 2026. https://my.clevelandclinic.org/health/diseases/24183-diabetic-nephropathy

7. National Institute of Diabetes and Digestive and Kidney Diseases. How Is Diabetes Related to Urinary Tract and Sexual Problems? NIDDK. July 26, 2023. https://www.niddk.nih.gov/health-information/professionals/diabetes-discoveries-practice/how-diabetes-related-to-urinary-tract-problems

8. Neuen BL, Young T, Heerspink HJL, et al. SGLT2 inhibitors for the prevention of kidney failure in patients with type 2 diabetes: a systematic review and meta-analysis. Lancet Diabetes Endocrinol. 2019;7(11):845-854. PMID 31495651. https://doi.org/10.1016/S2213-8587(19)30256-6

9. Palmer SC, Tendal B, Mustafa RA, et al. Sodium-glucose cotransporter protein-2 (SGLT-2) inhibitors and glucagon-like peptide-1 (GLP-1) receptor agonists for type 2 diabetes: systematic review and network meta-analysis of randomised controlled trials. BMJ. 2021;372:m4573. PMID 33441402. https://doi.org/10.1136/bmj.m4573

10. Toyama T, Neuen BL, Jun M, et al. Effect of SGLT2 inhibitors on cardiovascular, renal and safety outcomes in patients with type 2 diabetes mellitus and chronic kidney disease: a systematic review and meta-analysis. Diabetes Obes Metab. 2019;21(5):1237-1250. PMID 30697905. https://doi.org/10.1111/dom.13648