Acute kidney failure Whara whanewhane ohotata
Acute kidney failure (also called acute kidney injury) affects both your kidneys. It means that they have suddenly stopped working properly. It can happen at any age, but it is more common if you are aged 65 or over and have a long term health problem such as diabetes or heart failure.
Causes of acute kidney failure
Most cases of acute kidney failure are caused by reduced blood flow to the kidneys.
This reduced blood flow could be caused by:
- low blood volume after bleeding, excessive throwing up (vomiting), runny poos (diarrhoea) or severe dehydration
- your heart pumping out less blood than normal as a result of heart failure, liver failure or severe infection (sepsis)
- certain medicines that reduce blood pressure or blood flow to the kidneys, such as ACE inhibitors, certain diuretics or non-steroidal anti-inflammatoy drugs (NSAIDs).
Acute kidney failure can also be caused by:
- inflammation of the filters in the kidney (glomerulonephritis)
- a problem with the blood vessels (vasculitis)
- a problem with other structures in the kidney
- a blockage affecting the drainage of your kidneys like an enlarged prostate, a tumour in your pelvis or kidney stones.
Symptoms of acute kidney failure
You can sometimes have acute kidney failure without any symptoms, and it is only picked up by a blood test.
Common symptoms include:
- passing less wee than usual or none at all
- loss of appetite
- feeling sick (nausea) or throwing up (vomiting)
- feeling confused, anxious and restless or sleepy
- swelling of your legs or other body parts
- pain in your stomach or lower back.
Diagnosing acute kidney failure
It is essential that acute kidney failure is found early. The earlier it is picked up, the better the chance of your kidneys fully recovering.
Acute kidney injury is usually diagnosed from a blood test that measures the level of a substance called creatinine in your blood. High levels of creatinine mean that your kidneys are not getting rid of waste products as well as they should.
You may also need:
- urine tests to check for blood and protein
- an ultrasound scan of the kidney to pick up any blockages.
In rare cases, you may need a kidney biopsy to work out what is causing your acute kidney failure. This involves taking a very small sample of tissue from one of your kidneys.
Treating acute kidney failure
There is no specific treatment for acute kidney failure. The treatment aims to manage your symptoms and treat the underlying cause.
Sometimes you need dialysis to clean your blood by filtering out waste products and fluid until your kidneys recover.
Most people with acute kidney failure make a full recovery, but it may take some time for your kidneys to recover. You may get your normal kidney function back or you may only get some of it back.
Some people may have permanent kidney damage that needs dialysis. This is called chronic kidney disease.