Discoloured urine

The urine can become discolured in many conditions, yet they can be split into 3 categories:

  1. Blood in the urine (haematuria): This occurs when there is bleeding into the urinary tract caused by inflammation (cystitis/urethritis), trauma or urinary stones. Urine will have a red discolouration.
  2. Haemaglobinuria: Blood pigment, haemoglobin, can be excreted in the urine if red blood cells are being destroyed. These animals will have anaemia as well. Urine will have a red discolouration.
  3. Myoglobinuria: Myoglobin is produced from damaged muscle and can be excreted in the urine when there are large amounts of it being produced, i.e. when horses have azoturia (tie up). In these cases the urine has a brown discolouration.

Diagnosis

In cases of horses that have tied up the affected animal will be stiff, have painful muscles when touched and may be sweating up as well as having brown urine. In cases of red colouration of the urine it can be easy to diagnose whether it is blood or haemoglobin in the urine by analysing a sample. If it has been confirmed that there is blood in the urine an endoscope or ultrasound scanner may be used to help find the cause of the bleeding. See section on abnormal urination for treatments. In those cases with haemoglobin in the urine then the cause of this must be found, this can be an infection or tumour somewhere in the body.