Polycythemia is an elevation in the in the red blood cell count in the bloodstream. This condition can be relative, transient, or absolute.
Relative polycythemia occurs when the volume of plasma reduces and leads to a clear rise in red blood cell numbers. Relative polycythemia can result from something that brings about fluid loss from the blood e.g. dehydration from vomiting or diarrhoea.
Transient polycythemia is a form of relative polycythemia that is brought about when exhilaration or terror makes the spleen contract, consequentially releasing great numbers of red blood cells into the circulatory system. Treatment involves providing fluids to the affected animal and dealing with the fundamental cause.
Absolute polycythemia is an actual rise in the red blood cell count due to increased production. In order to diagnose this, a direct measurement of the entire number of red blood cells is done, something that isn’t possible in a majority of veterinary clinics. Your veterinarian will conduct blood and urine tests to assist in diagnosing polycythemia, and x-rays and other tests may be necessary in some cases. This disorder is associated with signs like red mucous membranes, a propensity to bleed, passing excessive quantities of urine, extreme thirst, seizures or behavioural changes, loss of coordination, loss of energy, and loss of sight.
Treating polycythemia involves removing red blood cells, via withdrawal of blood using a catheter placed in a vein. The blood is then replaced with fluids, with drugs like hydroxyurea or clorambucil being part of the treatment. The underlying ailment has to be treated first in most cases.