The right test for you

A comprehensive guide to testing, medical imaging and other health and illness prevention-related services. Click on the screening category to learn more about these services, individual tests & screening items

Kidney Function

Our kidneys filter blood, removing toxins, which are then excreted in urine. Kidney (renal) dysfunction will decrease their effectiveness at removing those toxins from the blood stream. Measuring levels of creatinine, urea, and also electrolytes enables determination of one’s renal function. Some symptoms of kidney dysfunction include: tiredness, lack of concentration, poor appetite, poor sleep; swelling or puffiness (oedema) around the eyes, wrists, ankles or tummy; foamy or dark-coloured urine or a decrease in urine volume.


Urea - also referred to as blood urea nitrogen (BUN) - levels are used to determine kidney or renal function. A blood test for urea will measure the level of urea in your blood. Urea is formed in the liver and is a byproduct resulting from the metabolism (breakdown) of protein. Following its formation in the liver, healthy kidneys filter the urea (and remove other waste products) from your blood, allowing the filtered byproduct to be excreted from the body in urine. If one's kidneys are not properly functioning, it may result in an accumulation of urea in the blood.