Symptoms and Treatments of Anemia in Dogs
Immune-Mediated Hemolytic Anemia
This is the most common cause of hemolysis in adult dogs. Red blood cell
destruction is caused by auto-antibodies that attack antigens present on the
surface of the cells, or by antigens from medications or organisms attached to
the red blood cell walls. The weakened cells are trapped in the spleen and
Poodles, Old English Sheepdogs, Irish Setters, and Cocker Spaniels are
predisposed to immune-mediated hemolytic anemia, but all breeds are
susceptible. Affected dogs are usually between 2 and 8 years of age; females
outnumber males four to one.
Most cases of immune-mediated hemolytic anemia are idiopathic. That is, the
reason why the auto-antibodies developed in that particular dog is unknown. In
some cases there is a history of recent drug therapy. An immune-mediated
hemolytic anemia also occurs with systemic lupus erythematosus.
The diagnosis is made by microscopic examination of blood smears, looking
for specific changes in the appearance of the erythrocytes and other blood
elements; and by serologic blood tests.
Treatment: Treatment of idiopathic immune-mediated hemolytic anemia is
directed toward preventing further red cell destruction by blocking the
antigen-antibody reaction using corticosteroids and immunosuppressants. Severe
anemia is corrected with blood transfusions. Splenectomy (removal of the
spleen) may be beneficial, but only when tests prove that the spleen is
contributing to the hemolytic process.
The response to treatment depends on the rate of hemolysis and whether an
underlying cause can be found and corrected. The outlook is guarded; even with
appropriate medical treatment, the mortality rate is close to 40 percent.
Congenital Hemolytic Anemia
Several inherited abnormalities in the structure of red blood cells can
result in their premature destruction. Phosphofructokinase deficiency is an
autosomal recessive trait that occurs in English Springer Spaniels and Cocker
Spaniels. A deficiency of this enzyme results in changes in the pH of red blood
cells, causing the cells to periodically fragment and produce bouts of
hemoglobinuria. There is no effective treatment.
Pyruvate kinase deficiency is another red blood cell enzyme deficiency
caused by an autosomal recessive gene. This disease is recognized in several
breeds, including Basenjis, Beagles, and West Highland White Terriers. Puppies
usually develop the hemolytic anemia at 2 to 12 months of age. Death by age 3
is the usual outcome.
Genetic tests for phosphofructokinase and pyruvate kinase deficiency are
available through the University of Pennsylvania at PennGen, and from OptiGen