​Kidney disease can be silent in the early stages and the patient may be perfectly well without any symptoms. However, patients usually need urine and blood tests to detect renal disease apart from a physical check-up.

The urine is usually tested for:

• the presence of blood, a condition known as haematuria.
• the presence of protein or proteinuria
• cellular debris (also called casts)
  
  The blood is also tested for abnormally high levels of substances that accumulate in the body in the presence of kidney failure. They include:

• the blood urea level
• the blood creatinine level
• other substances such as potassium and bicarbonate
  
  The initial screening tests can be done at a clinic with a sample of freshly collected urine. The urine is tested using a urine test strip. The urine test strip is a strip adhered to several chemicals pads that change their colour when there are abnormal amounts of blood, protein, or sugar in the urine. In the presence of abnormal urine test strip testing, patients may need to collect their urine for 24 hours. This will allow the attending doctor to better assess the urine to confirm or exclude any urinary abnormality. Some patients may eventually need a kidney biopsy to distinguish the type of kidney disease and evaluate the eventual kidney prognosis. A kidney biopsy is a minor surgical procedure in which a needle is inserted into the kidney (with local anaesthesia), and a piece of the kidney is taken for microscopic examination.
  
  It is important to realise that the presence of a single abnormal lab result does not necessarily equate to the presence of renal disease. An abnormal laboratory result implies that the patient needs to see a doctor. The doctor may consider either a repeat test or more extensive testing for the patient. While many people can benefit from having these tests done, certain patients at higher risk of kidney disease should have regular renal function tests. These groups include patients with:

• High blood pressure
• Diabetes mellitus
• Gout
• History of haematuria (blood in the urine)
• Recurrent urine infections
• History of protein in the urine
• Family history of kidney disease