Membranoproliferative glomerulonephritis (MPGN)

Symptoms and signs

Blood in the urine

When red blood cells leak through the kidney’s filters into the urine, this causes haematuria (blood in the urine). Sometimes you cannot see the blood, but if there is a lot, the urine may be coloured red or dark brown (like blackcurrant squash or a cola drink).

Protein in the urine

When proteins leak through the kidney’s filters into the urine, this causes proteinuria (more protein in the urine than normal). You cannot usually see the protein, but occasionally it can make the urine look frothy. Protein is an important part of our diet and is in most foods. When we eat protein, it is digested (broken down) in the stomach and gut and taken into the blood.

Problems urinating

Some children urinate less often or pass smaller amounts.

Swelling

Some children have swelling or puffiness in different parts of their body, especially around their eyes, legs and feet (oedema).

Swelling in the tummy and breathlessness

• A few children get a large swelling around their tummy (ascites). It happens when fluid builds up in the peritoneal cavity, which is the area around the organs in the abdomen (tummy).
• A very small number of children feel breathless. This happens when fluid builds up around their lungs.

Other symptoms and signs

The below are occasionally found in children with MPGN:

• feeling tired, low energy or difficulty concentrating
• decreased appetite (not wanting to eat)
• nausea (feeling sick) or vomiting (being sick), or diarrhoea
• pain in the tummy
• headaches that keep coming back or that do not go away
• pain, stiffness or swelling of the joints.

Complications

Some children have more complications – health problems that happen because of the condition or its treatment. These are more rare. Your child’s healthcare team will carefully check for these, and speak with you about any treatment that your child may need.

High blood pressure

MPGN can cause blood pressure that is too high (hypertension). In some children, this causes headaches, vomiting or blurred (fuzzy) vision. Hypertension that lasts a long time can also increase the risk of getting other diseases in adulthood.

Risk of infections

Some children with MPGN are treated with medicines that suppress, or damp down, their immune system, which normally protects the body from infections. These children are more likely to get infections.

Rapidly progressive glomerulonephritis

Occasionally, MPGN gets worse quickly – this is called rapidly progressive glomerulonephritis (RPGN) or crescentic glomerulonephritis. If this happens, your child will need to take medicines and may need more intensive treatment, such as dialysis. Some children with RPGN will get better, but a few will need long-term dialysis before they can have a kidney transplant.

This is one cause of acute kidney injury – when the kidney quickly stop working as well as they should, over a short time.

Symptoms and complications

What happens in the kidneys

In MPGN, a protein called complement gets trapped in the tiny kidney filters (glomeruli). Complement is part of the immune system, which normally protects the body from infection and disease. Doctors think that the complement in the glomeruli is causing the MPGN.

The immune system

Many germs – including bacteria and viruses – can make us sick if they get into the body. The immune system can kill these germs. However, if the immune system is not working properly, it can start to cause problems.

Types of MPGN

There are three types of MPGN. These are identified by the pattern of complement that is trapped in the glomeruli.

• Type 1 and type 3 are very similar.
• Type 2 is different. It also called dense deposit disease (DDD) because there are dense (thick) deposits of complement trapped in the glomeruli.

The complement system is made up of proteins that work with other parts of the immune system. It is normally only activated (made to work) when it is needed. This happens in different ways.

Will it affect other family members?

Doctors do not think that MPGN runs in families. If one of your children has this type of glomerulonephritis, it is unlikely that another of your children or another family member will get it.

Your child will need some tests to diagnose (identify) MPGN, find out more about how it is affecting him or her and whether any treatment is needed. Your child may need an examination, urine tests, blood tests, imaging tests and a kidney biopsy.

Examination

Your doctor will talk to you or your child about his or her symptoms and any medicines that he or she takes. The doctor will examine your child – for example, to see whether he or she has oedema (swelling in their body). Your doctor or nurse will check your child’s blood pressure. This is because MPGN may cause high blood pressure (hypertension).

Urine tests

You, or a nurse, will need to collect some of your child’s urine in a small, clean container for a urine test. A dipstick will be dipped into the urine – this is a strip with chemical pads that change colour depending on what substances are in the urine. This shows whether there are blood cells and/or protein, which are signs of MPGN. The sample may also be sent to a laboratory for more accurate tests.

Blood tests

A small amount of blood will be taken from a vein, with a needle and syringe, for a blood test. A special gel or cream can be used to help your child stop feeling any pain. The blood test results can give the doctor more information, including:

• about the immune system, and whether there has been a recent infection
• how well his or her kidneys are working – this is called the kidney function
• the amount of protein in your child’s blood – in MPGN, the kidneys leak protein into urine and this is sometimes enough to affect how much is in the blood.

Imaging tests

Some children need imaging tests (scans). These use special equipment to get images (pictures) of the inside of their body.

• Ultrasound scan – looks at the shape and size of kidneys and other parts of the urinary system. A small handheld device is moved around your child’s skin and uses sound waves to create an image on a screen.
• Chest X-ray – for children with breathing problems, this test checks for any fluid (liquid) around the lungs. Your child sits or lies still for a few seconds while a machine takes X-ray images.

Occasionally, other imaging tests are needed.

Kidney biopsy

Your doctor can diagnose MPGN with a kidney biopsy, and may recommend this test. A tiny piece of one kidney is removed from the body with a needle, and examined under microscopes. Special medicines are used so your child does not feel any pain or can sleep through the procedure.

A kidney biopsy can give more information about how much damage there is in your child’s kidney, and confirm whether he or she has MPGN or another type of glomerulonephritis. The kidney biopsy also shows the type of MPGN – type 1, type 2 (dense deposit disease) or type 3. It can take a few weeks to get the results.

When your child first develops MPGN, he or she probably needs to stay in hospital for a few days to be carefully monitored.

Some children need to take steroid medicines. Some will need other treatment for complications, such as swelling in their body and high blood pressure. These are explained below.

A few children will need dialysis, which uses special equipment to remove waste from the body if their kidneys are not working well enough.

Where will my child be treated?

Your child will probably be referred to a paediatric renal unit, a specialised unit that treats babies, children and young people with kidney conditions and may be in a different hospital to your own. He or she will be looked after by a team, including a paediatric nephrologist, a doctor who treats children with kidney problems.

Outpatient

Your child can go home when the doctor thinks that his or her health is stable. Often, your child will need to visit the hospital during the day – as an outpatient – for check ups or more treatment.

Steroids

Your paediatrician may prescribe a steroid medicine to your child – this is usually the medicine prednisolone. Steroids are chemicals that are made naturally in the body but can also be made as medicines. They suppress the immune system, or make it less active. Your doctor will work out the amount of medicine (the dose) that is right for your child. The dose will be shown on the medicine label. Your child may need to take a large dose each day to start with, and then the dose is slowly reduced. Your doctor will usually monitor blood and urine tests to help decide when to change doses.

Vaccines

It is important that your child has the vaccines (immunisations) that he or she needs to reduce the risk of some diseases. Speak with your doctor about these – some vaccines are not safe to give while a child is taking steroids.

Infections

Children taking these steroids are more likely to get infections. Speak with your doctor or nurse, and your child’s teacher or daycare manager, about how you can help prevent infection. Contact your doctor straight away if your child:

• has been in contact with someone who has chicken pox (if they have not had this illness before) or measles (if they have not had the MMR vaccine, which protects against measles, mumps and rubella);

or

• is unwell and you are worried about an infection. If your child does get an infection, he or she may need to take an antibiotic medicine, which kills the germs that cause infection. Your child must take the medicine for the number of days that the doctor has told you, or until all of the medicine has been taken.

If your child does get an infection, he or she may need to take an antibiotic medicine, which kills the germs that cause infection. Your child must take the medicine for the number of days that the doctor has told you, or until all of the medicine has been taken.

Medicines for Children advice about antibiotics

Side-effects you need to do something about

We use medicines to help children get better, but sometimes they have effects we do not want – side effects. Contact your doctor straight away if your child has any of the following while on steroid medicines:

• fever (temperature above 38°C), with a sore throat or a cough
• a rash or severe bruising
• bad stomach pain or repeated vomiting – sometimes steroids can cause ulcers in the stomach.

Other side-effects

Other side-effects that affect some children are below – speak with your doctor or nurse if you are concerned or need more support:

• nausea, vomiting, stomach pain and/or indigestion (heartburn) due to irritation to the lining of the stomach – your doctor may give your child some medicine to treat this
• behavioural problems – you may find that your child is more likely to have tantrums, be moody, feel depressed, have difficulty sleeping or have nightmares
• weight gain and larger appetite – you can help by making sure your child has lots of physical activity and eats fruits, vegetables and low-calorie food, rather than food that is high in calories (such as cakes, biscuits, sweets and crisps), and by reducing the portion size
• high blood pressure (hypertension) – your child’s blood pressure will be regularly checked, and if it is too high, will need to be controlled by adjusting the amount of fluid drunk or taking medicines.

There may, sometimes, be other side-effects that are not listed above. If you notice anything unusual and are concerned, contact your doctor.

Changes to eating and drinking

Your child may need to make temporary changes to what he or she eats – for example, less salt and less of certain foods. He or she may also need to drink less fluid, such as water, squash and soft drinks. Your doctor, nurse or a paediatric dietitian will help you and your child make these changes.

Controlling blood pressure

Some children with MPGN have high blood pressure (hypertension). If your child has hypertension, he or she may need to change what they eat and drink, and may need medicines, to control the blood pressure.

Reducing protein loss in urine and controlling blood pressure

Some children need to take medicines for:

• proteinuria – to reduce the amount of protein lost in their urine, and/or
• hypertension – to reduce or control blood their pressure so it is in the healthy range.

These are usually medicines called angiotensinconverting enzyme inhibitors (ACE inhibitors) or angiotensin-II receptor blockers (ARBs). Common ACE inhibitors are: captopril, enalapril and lisinopril.

Research suggests that, in some children, these medicines will reduce the risk of long-term kidney problems.

Reducing swelling in the body – diuretics

Very occasionally, children with MPGN need to take diuretics, medicines that help reduce oedema (swelling in the body). Diuretics work on the kidneys to increase the amount of water and salt they remove from the body in urine.

If your child is taking diuretics, he or she will need to go to follow-up appointments. Your doctor will examine your child for oedema and measure his or her weight. This helps find out how well the medicine is working.

Common diuretics are: furosemide, spironolactone and metolazone. Some of the other diuretics that may be used are: amiloride, bendroflumethiazide and chlorothiazide.

Managing reduced kidney function

For some children, the kidneys do not work as well as normal during this illness – they have reduced kidney function. The severity of this varies, but most do not need any special treatment and their kidney function will return to normal.

A small number will have more serious kidney problems, and will need further treatment. Dialysis uses special equipment or a machine to ‘clean’ the blood, removing waste products and extra water and salts. Most of these children need this treatment for a short time only, but a few need it for longer.

Your child’s healthcare team will give you information to help make sure your child has the best type of dialysis.

Questions to ask the doctor or nurse

• What treatment does my child need?
• How will the treatment help my child?
• How long will my child be in hospital?
• How can I help my child prepare for procedures and treatments?
• If the first treatment does not work in my child, what happens next?
• How will I know if we need to go back to the hospital or see the doctor?
• Will the MPGN come back? How will I know?

MPGN is a chronic condition, which means that it does not go away quickly, and may last for years. Most but not all children with MPGN will have long-term kidney problems. Your doctor will speak with you about how MPGN might affect your child in the future.

Urine testing at home

Your doctor may ask you to do urine tests at home to find out whether the MPGN has gone away (gone into remission) or whether it comes back (has a relapse). You will be given special, clean containers to collect the urine, and dipsticks to dip into the urine and check for any protein and/or blood in the urine. Your child’s healthcare team will show you how to do this. If there is proteinuria (a lot of protein in the urine), you will need to tell your doctor, and bring the urine sample for further testing. This may mean there is a greater risk that your child will develop long-term kidney problems.

Follow up

All children with MPGN need follow-up appointments at the hospital or clinic, to check for any health problems. These may continue throughout childhood and sometimes adulthood.

It is important to go to these appointments, even if your child seems well – remember to bring the results from your home urine testing. You will also have the opportunity to ask any questions. At these appointments, your child may have:

• his or her height and weight checked
• a physical examination
• urine tests – to check for blood, protein and other substances in his or her urine
• blood tests – to check for the amount of protein and other substances in his or her blood, and measure his or her kidney function
• his or her blood pressure measured.

Medicines

Some children need to take angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin- II reception blockers (ARBs) over a long time, and sometimes into adulthood. 

Common ACE inhibitors are:

• captopril
• enalapril, and
• lisinopril.

Doctors understand that, in some children, these medicines may reduce the risk of long-term kidney problems.

Long-term effects

Children with type 2 MPGN (dense deposit disease) are more likely than children with type 1 or type 3 MPGN to have more serious problems.

Chronic kidney disease

Some children may progress to later stages of chronic kidney disease (CKD) – their kidneys stop working as well as they should. CKD may progress to final stages of CKD (kidney failure), and these children may need specialist treatment, including dialysis and/or a kidney transplant.

Sometimes a child who had MPGN before the kidney transplant can get the disease again in the new kidney. However, this is usually less serious and does not always affect the kidney function.

If your child has progressed to later stages of CKD, you will learn more over time about what to expect and how to help manage the condition.

Impact on your child and your family

Children who have been successfully treated for MPGN can usually do the things that other children their age do. They should be able to continue going to school or nursery. They can play with other children and stay active.

Living healthily

Your child can help protect his or her kidneys by leading a healthy lifestyle through their child and adult years. This includes:

• eating a healthy diet – with at least five servings of fruit and vegetables a day, taking care not to eat too much salt, sugar and fats (especially saturated fats)
• getting plenty of exercise
• not smoking.

Further support

This can be a difficult and stressful experience for your child and the whole family, including other children.

Further information

This is the end of the information on MPGN. If you would like to read more about other kidney conditions, tests and diagnosis, treatment or supporting information, you can find a list of topics covered on the infoKID website at www.infoKID.org.uk.

© BAPN and Kidney Care UK 2013-2022, all rights reserved.

For details on any sources of information used in this topic, please contact us through the contact us form on our website www.infoKID.org.uk.

We take great care to make sure that the information in this leaflet is correct and up-to-date. However, it is important that you ask the advice of your child’s doctor or nurse if you are not sure about something. This information is intended for use in the United Kingdom, and may not apply to other countries. The British Association of Paediatric Nephrology (BAPN), Kidney Care UK and the contributors and editors cannot be held responsible for the accuracy of information, omissions of information, or any actions that may be taken as a consequence of reading this information.