Kidney Disease

What is chronic kidney disease or failure?

Kidney disease develops when there is an abnormality present in the structure or function of one or both kidneys. Clinical symptoms of kidney disease develop when kidney function has deteriorated a significant amount (up to 75%), as a result it can progress for some time without being noticed. Blood and urine tests are used to detect kidney disease.

What are the functions of the kidney?

  • To filter and eliminate waste products from the blood

  • Produce hormones

  • Control of red blood cell production

  • Maintain hydration through water and electrolyte balance

What are the types of kidney disease?

1. Acute – sudden onset and develops over a few days. In some cases can be reversible.

2. Chronic – insidious onset, may be present for months to years and is irreversible. Treatment of chronic kidney disease is aimed at slowing down the progression of the disease. It is also important to note that the underlying cause of chronic renal disease is often unknown as the disease tends to be present for some time before diagnosis.

What are the symptoms of chronic renal disease?

Symptoms of kidney disease result partially from the inability of the kidneys to concentrate urine. As kidney function declines further the ability of the kidney to elimate waste products from the body declines and these start to build up in the body – this is called uraemia and the toxins are referred to as uraemic toxins. This helps us to understand the variety of clinical symptoms that develop which are listed below:

  • Increased thirst

  • Increased urine volume

  • Weight loss

  • Poor hair coat

  • Reduced/selective appetite

  • Loss of appetite

  • Vomiting

  • Anaemia

  • Weakness

  • Lethargy

  • Bad breath

  • Mouth ulcers

What test are performed?

  • Urinalysis – this will let the vet know how well the kidneys are concentrating the urine. As kidney disease progresses urine becomes more dilute. Any signs of a urinary tract infection can also be detected. Urine protein levels may be checked also, levels increase as disease progresses.

  • Biochemistry – allows the vet to check the levels of urea and creatinine which are two waste products produced by the body that the kidneys should eliminate. The levels of urea and creatinine increase as kidney disease progresses.

  • Haematology – assess degress of anaemia. The kidney produces a hormone called erythropoetin which is involved in red blood cell production. As kidney function declines, hormone production and red blood cell levels also decline.

  • Phosphorus, potassium and calcium – levels of all three are monitored as they can change.

  • Blood pressure measurement – high blood pressure can lead to further decline in kidney function.

  • Ultrasound and x-ray – may be done to evaluate the structure of the kidneys.

  • Further tests may be performed to evaluate kidney function further, which your vet will discuss with you if they think they are necessary. This include blood urea nitrogen and creatinine concentrations.

Treatment of kidney disease?

Treatment of kidney disease depends on the severity of the condition at the time of diagnosis.

1. Diet – low in protein, phosphorus and salt. These diets help to reduce clinical symptoms and delay progression of the disease.

2. Good hydration

3. Manage blood pressure, anaemia, electrolytes imbalances if present with oral treatments

4. Intravenous fluid therapy – often required to treat the uraemia (the build up of toxins in the system).