Introduction

Polycythemia, a condition in which the number or concentration of circulating red blood cells is actually or apparently elevated, can contribute to a number of different clinical signs, depending upon why the condition occurred in the first place.

Symptoms of Canine Polycythemia

There are several different forms of polycythemia, each of which can cause symptoms that may appear slowly or suddenly. Owners of affected dogs may notice one or more of the following signs:

• Behavior changes
• Abnormal motor skills
• Abnormal sensory skills
• Paroxysmal sneezing (sudden; intense; recurrent)
• Nose bleeds (epistaxis)
• Injected mucous membranes (brick red gums)
• Cyanotic mucous membranes (pale gums)
• Enlarged spleen (splenomegaly; palpable)
• Enlarged liver (hepatomegaly)
• Increased thirst and/or water intake
• Increased volume and/or frequency of urination

Unusually high concentrations of oxygen, carried by unusually high numbers of circulating red blood cells, can cause mild to severe tissue damage over time. Left untreated, polycythemia – especially the absolute form of the disease can lead to additional symptoms, including:

• Lethargy
• Weakness
• Confusion
• Difficulty walking/ambulating
• Exercise intolerance (fatigue)
• Difficulty breathing (dyspnea)
• Lack of coordination (ataxia)
• Lack of interest in play and/or normal social interactions
• Seizures (rare)
• Uncontrolled shaking
• Vision impairment

Dogs experiencing these symptoms should be taken to their veterinarian.

Dogs at Increased Risk

There is no particular breed, age or gender predisposition to the development of polycythemia in domestic dogs.