Kidneys Nephrotic Syndrome

Overview

Nephrotic syndrome is not a single disease. It is a group of signs that appear when the tiny filters inside your kidneys (called glomeruli) become damaged and start leaking protein from your blood into your urine. Protein in the blood normally acts like a sponge, holding water inside your blood vessels. When too much protein leaks away, water escapes into your body tissues, which causes swelling — often around the eyes, ankles, feet and belly. Nephrotic syndrome is usually treatable, and many people recover well, although some need long-term care and monitoring.

Nephrotic syndrome is uncommon. It is seen most often in young children, and it is rarer in adults. Because it is uncommon, doctors often arrange extra tests to find the underlying cause.

It can affect anyone, at any age. In children it most often appears between about 2 and 6 years old, and boys are affected slightly more often than girls. In adults it is more likely to be linked to another health condition, such as diabetes, an immune system problem, an infection, or a reaction to a medicine. In pregnant women, swelling and protein in the urine can be a sign of pre-eclampsia, which needs urgent medical attention.

Symptoms

Common symptoms

• Swelling (puffiness) around the eyes, especially first thing in the morning
• Swelling in the feet, ankles and legs that may leave a dent when you press the skin
• Swelling or a bloated feeling in the belly
• Sudden weight gain from extra fluid, not from eating more
• Urine that looks frothy or bubbly
• Feeling very tired or lacking energy
• Poor appetite, or feeling full quickly
• Feeling generally unwell, or more infections than usual

Symptoms in children

• Puffy eyelids or a swollen face when waking up
• Swelling in the legs, feet, or sometimes the scrotum or labia
• Tummy pain, a swollen tummy, or loose stools
• Being irritable, unusually sleepy, or less playful
• Eating less, or refusing feeds in babies and toddlers
• Nappies or urine that look frothy

Symptoms in older adults

• Swelling in the legs and ankles that gets worse during the day
• Breathlessness, especially when lying flat or with mild activity
• Feeling very tired, weak, or low in energy
• Unexplained weight gain over days or weeks
• A higher chance of blood clots, which can show up as a swollen painful leg or sudden breathlessness
• Confusion or feeling generally unwell if the kidneys are struggling

Causes

Main causes

• In children, the most common cause is a condition called minimal change disease, where the kidney filters look normal under a microscope but leak protein. Its exact cause is not fully understood.
• Immune system kidney diseases, where the body's defence system mistakenly attacks the kidney filters
• Diabetes, which can damage kidney filters over many years
• Infections such as hepatitis B or C, HIV, and some other infections
• Certain medicines, including some pain relievers and some antibiotics
• Conditions that cause abnormal proteins to build up in organs, such as amyloidosis
• Some cancers, particularly cancers of the blood and lymph nodes
• Inherited (genetic) kidney problems
• Pre-eclampsia in pregnancy, which is a serious condition needing urgent care

Risk factors

• Having diabetes, lupus, or another autoimmune condition
• A family history of kidney disease or nephrotic syndrome
• Having a current or past infection linked to kidney problems
• Taking certain medicines long term, especially some pain relievers
• Being pregnant (as a possible sign of pre-eclampsia)
• Having certain cancers, especially of the blood or lymph system

When to see a doctor

See a doctor urgently if:

• Swelling that has come on quickly, or is getting worse over days
• Frothy urine together with swelling anywhere on the body
• Passing much less urine than usual
• Fever or feeling very unwell with any of these symptoms
• Breathlessness or a swollen, painful leg (call emergency services if sudden or severe)

Book a routine appointment if:

• Swelling around the eyes or ankles that keeps coming back
• Unexplained weight gain or puffy eyes in the morning
• Urine that often looks frothy
• Ongoing tiredness with swelling
• You have a condition such as diabetes and notice new swelling

Diagnosis

Your doctor will start by asking about your symptoms and examining you, including checking your blood pressure and looking for swelling. A simple urine test can show whether there is protein in your urine. If nephrotic syndrome is suspected, blood tests and a collection of urine over a day may be arranged to measure the protein levels. Depending on your age and results, you may be referred to a kidney specialist (nephrologist), and some people need a kidney biopsy — a small sample of kidney tissue taken with a fine needle — to find the exact cause.

Tests that may be done

• Urine dipstick test, done in the clinic, to look for protein
• A urine sample sent to the lab, or a 24-hour urine collection, to measure protein
• Blood tests to check protein levels, cholesterol, and how well the kidneys are working
• Blood pressure measurement
• Blood tests to look for other conditions such as diabetes, lupus, or infections
• An ultrasound scan of the kidneys
• A kidney biopsy in some cases, especially in adults, to find the exact cause

What to expect at your appointment

Most tests are quick and painless apart from a blood test. A 24-hour urine collection means collecting all your urine at home over a full day and returning the container. A kidney biopsy usually involves a short hospital visit, a small needle, and a few hours of resting afterwards; you may have some mild soreness for a day or two. Results can take a week or more, so there may be a wait before the full picture is clear. Your doctor will explain each step and what it means for you.

Treatment

Treatment aims to do three things: reduce the protein leak, control swelling, and treat any underlying cause. The right plan depends on your age, the cause, and how your kidneys are working. Many people improve within weeks of starting treatment, and some children grow out of the condition completely.

Self-care at home

• Follow the advice you are given about salt and fluids — this helps control swelling
• Weigh yourself regularly if your care team asks you to, and note any rapid changes
• Take your medicines exactly as prescribed, and ask your pharmacist before taking any new medicine, including pain relievers
• Keep up with your vaccinations as advised by your care team
• Rest when you need to, and plan for extra rest during flare-ups
• Keep all follow-up appointments and urine tests, even when you feel well

Medical treatments

Treatment is tailored to the cause. Medicines called water tablets can help the body get rid of extra fluid and reduce swelling. Other medicines lower blood pressure and protect the kidneys, and some people need medicines that calm the immune system — for example, steroid tablets — when the cause is an immune problem. If an infection, diabetes, or another condition is behind the problem, treating that condition is a key part of care. People with high cholesterol may be offered treatment to protect the heart, and some need medicines to reduce the risk of blood clots. In children, the first treatment is often a course of steroid medicine, with close monitoring. Your care team will explain the options for your particular case, including the benefits and side effects.

When is surgery considered?

Surgery is not usually part of treatment for nephrotic syndrome. Rarely, other operations may be needed for related problems, and your specialist team would discuss this with you if it applied.

Living with this condition

Most people with nephrotic syndrome can carry on with school, work and family life, with some adjustments. There will be clinic visits and urine tests, and possibly short courses of extra treatment when the condition flares up. Keeping a simple diary of your weight, swelling and how you feel can help you and your care team spot changes early.

Lifestyle tips

• Eat a balanced diet and keep salt moderate to help control swelling
• Ask your care team whether you need to change how much protein you eat — advice varies from person to person
• Stay active in a way that suits you; gentle exercise such as walking helps circulation and mood
• Avoid smoking, and keep alcohol within sensible limits
• Avoid contact with people who are clearly unwell when your treatment lowers your immunity
• Wash your hands well and keep food hygiene high, because infections can be more serious
• Ask your pharmacist or doctor before taking any over-the-counter pain reliever or supplement

Diet and exercise

A dietitian can help you plan meals that suit your kidneys, including advice on salt, protein and fluids. Many people do not need strict limits, so get individual advice rather than cutting foods out on your own. Regular gentle activity — walking, swimming, cycling, or playing — helps your heart, keeps muscles strong, and supports your mood. Build up slowly, especially during a flare-up, and rest when your body asks for it.

Mental health and emotional wellbeing

Living with a long-term kidney condition can be worrying, especially for parents of affected children. It is normal to feel anxious, tired, or low at times. Swelling can change how you look, and appointments can take up a lot of time and energy. Talking to someone — a friend, your GP, or a counsellor — really does help. If you ever feel hopeless or have thoughts of harming yourself, please reach out for crisis support straight away: contact your local emergency number, or a crisis line in your country. You do not have to cope alone.

Prevention

Nephrotic syndrome cannot always be prevented, because many causes are linked to the immune system or to genes. But some causes can be lowered in risk: keeping diabetes well controlled, treating infections promptly, and avoiding unnecessary long-term use of certain pain relievers all help protect the kidneys. Anyone with a long-term condition that can affect the kidneys should have regular checks.

Vaccines

Infections can be more serious when you have nephrotic syndrome or take medicines that lower your immunity. Your care team may recommend extra vaccinations, such as flu, pneumonia, and hepatitis vaccines. Ask your GP or pharmacist which vaccinations are right for you or your child, and when to have them — some vaccines should not be given during certain treatments.

Screening programmes

There is no routine screening programme for nephrotic syndrome. However, a simple urine test for protein is often included in checks for people with diabetes, high blood pressure, or a family history of kidney disease. If you have any of these risk factors, ask your doctor whether your kidney health should be checked.

Complications

If left untreated

• Infections, because proteins that fight infection are lost in the urine and immunity can be lowered by treatment
• Blood clots, because the blood becomes more likely to clot when protein levels are low
• High cholesterol and a higher long-term risk of heart problems
• Poor nutrition and slowed growth in children if the condition is not well managed
• Kidney damage that gets worse over time, and in some people kidney failure needing specialist treatment
• Low blood pressure or kidney strain from too much fluid loss or certain treatments

Long-term outlook

The outlook is good for many people. Most children with the common childhood form respond well to treatment and many grow out of it, though some have relapses that need further treatment. Many adults also do well once the cause is found and treated. Some people need long-term monitoring and treatment, and a small number develop lasting kidney problems. With regular check-ups, the right treatment and good self-care, most people can live full and active lives.

Find support

External links open third-party websites. Ruqelo Health is not responsible for external content. Listing an organisation does not imply endorsement.