Some children do not have any symptoms of AKI and it may only be found during a routine blood test.
For those that do have symptoms, these may include:
- blood in the urine (haematuria) – you cannot always see the blood, but if there is a lot, the urine may be coloured red or dark brown (like a cola drink)
- producing less urine than usual or none at all
- swelling or puffiness (oedema) in different parts of the body, especially around the eyes, legs and feet. This happens in some children who have AKI that is caused by glomerulonephritis, which is a group of conditions affecting the kidney filters, the glomeruli. Swelling happens when damaged glomeruli are unable to filter enough salt and water out of the blood stream into the urine.
In some types of glomerulonephritis, the damaged glomeruli are not able to filter enough salt and water out of the bloodstream into the urine. After a while, there is too much salt and water in the body, which causes the swelling.
These symptoms may appear suddenly over just a few days. Take your child to the doctor as soon as possible if they have any of these symptoms.
Other symptoms of AKI include:
- being very thirsty
- feeling or being sick
- excessive tiredness
- low energy
- finding it difficult to concentrate
- confusion
- getting out of breath easily
- dizziness
- unexplained weight gain
In serious cases, some children may have a seizure (also called a fit or convulsion).
Complications of AKI
Some children can develop other health problems or complications because of their AKI. These may include:
High blood pressure
AKI can cause hypertension – high blood pressure. In some children, this causes headaches, vomiting or blurred (fuzzy) vision. Hypertension that lasts a long time can also increase the risk of getting heart disease in adulthood. Your doctor or nurse can check your child’s blood pressure and help them to keep it within a safe range. Your child may may need to reduce the amount of salt they eat or make other changes to their diet. Some children take medicines to help control their blood pressure.
Too much fluid in the body
In AKI, when the kidneys are not functioning fully, this can cause too much fluid (water) to build up in the body – this is called fluid overload and can cause the swelling (oedema) mentioned earlier.
If your child has fluid overload, your kidney team will limit the amount of fluid that your child can drink and will prescribe medicines to try and help their kidneys to produce more urine. Sometimes they have to use a machine to do the work of the kidneys to remove the extra fluid.
In rare cases, fluid can build up in the lungs, which may cause breathlessness – this is called pulmonary oedema.
Other, rare complications include:
- Hyperkalaemia - a build-up of potassium in the body
- Acidosis - a build- up of acid in the body. This may cause rapid breathing.