Poststreptococcal glomerulonephritis (PSGN)
Poststreptococcal glomerulonephritis (PSGN)
Key points to remember
- poststreptococcal glomerulonephritis (PSGN) is a kidney disease that develops 10 to 14 days after a skin or throat infection
- it is not caused by the bacteria itself, but by the body's infection fighting (immune) system
- the main symptoms are blood in your child's wee (urine) and swollen ankles or puffy eyes
- your child will need their blood pressure, weight and wee checked regularly. They will also need a blood test to check kidney function
- most children (95 percent) recover fully with no long-term complications
- it is very important to take your child to any follow-up appointments to make sure they make a full recovery
What is it?
PSGN is a kidney disease that occurs 10 to 14 days after a throat or skin infection caused by Streptococcus (a type of bacteria).
What causes it?
PSGN is not caused by the streptococcal bacteria directly, but by your child's infection fighting (immune) system. When your child's body tries to fight an infection, it makes antibodies. Antibodies are the part of the infection fighting (immune) system used to identify bacteria so they can be destroyed. Usually the dead bacteria (in this case the Streptococci) and antibodies are cleared from the child's body without any problems. However, in PSGN they become trapped in the filters of the kidneys called the glomerulus. This causes inflammation, which slows down the filters of the kidneys, making it harder for them to make urine and get rid of the waste.
How infectious is it?
You cannot 'catch' PSGN as it is caused by the body's own infection fighting (immune) system. However, streptococcal infections (either from the skin or throat) can be spread from person to person.
What are the signs and symptoms?
These can be varied. Some children may have no symptoms, or they may:
- have blood in their wee (haematuria). This may make the wee dark or brown coloured. Sometimes it is only discovered when the wee is tested
- have swelling (oedema) - fluid collects in the tissues and can cause puffiness around the eyes or the ankles
- do less wee each time and/or wee less often
- have high blood pressure (hypertension)
- have protein in their wee (proteinuria)
- have increasing tiredness
How is it diagnosed?
PSGN is diagnosed based on your child's signs and symptoms and lab tests. Your doctor will check your child's wee for protein and blood. Your child will also get a blood test to check kidney function, signs of a recent streptococcal infection and the effect of the infection on the immune system. The doctor may also check for other things in the blood to rule out other conditions and different causes of glomerulonephritis.
What treatment is available or required?
PSGN gets better on its own, so treatment is based around relieving symptoms and trying to prevent complications. Your child may need to be on restricted fluid and salt intake. They may need medicine to bring their blood pressure down, or medicine to encourage the kidneys to get rid of salt and water. The doctor will usually give your child antibiotics to treat any streptococcus bacteria left in their body.
How long could it last?
Most children make a full recovery within a few weeks. The blood you can see in the wee is usually gone in 2 weeks and the high blood pressure comes down in about 4 weeks. Urine tests may still show blood and protein in your child's wee for up to 2 years.
What followup is required?
Your child will continue to have their blood pressure, weight and wee checked once they've left hospital. Once this followup has finished it is important that you return to your family doctor if you notice any of the signs and symptoms recurring. If at any stage you have concerns about your child's health don't hesitate to seek medical advice.
What are the possible complications?
Most children make a complete recovery. However, for a small number of children the disease will continue and for an even smaller number of children the disease may get worse. The main things your doctor will look out for are:
- continuing high blood pressure (hypertension)
- poor kidney function
- prolonged loss of protein in the urine (proteinuria) which may not cause obvious symptoms
- headaches and seizures
How can I care for my child at home?
It is important you make sure your child takes any prescribed medicine. It is also important you take your child to their followup appointments where your doctor will check your child's blood pressure, weight and wee.
How can this be prevented?
If streptococcal skin or throat infections are discovered early they can be treated with antibiotics, which may prevent the development of PSGN.
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