© Kirrawee Veterinary Hospital CANINE DISEASES
Auto-immune Hemolytic Anemia
Hemolytic Anemia is the loss of red blood cells due to their destruction.
Immune-mediated hemolytic anemia is when the red cells are destroyed
by the bodies own defenses (the immune system). It is thought
that drugs, viruses, or parasites such as hemobartonella may attach
to the red blood cells causing them to be recognized as foreign
by the immune system. The defense cells (white blood cells, or
leukocytes) then either completely destroy the red cell or damages
outer skin producing a smaller cell the spherocyte. Spherocytes
are usually trapped within the spleen and removed from circulation.
The end result is a deficiency of normal red blood cells (anemia). Clinical signs of anemia are panting, weakness, pales gums and
rapid heart rate. Yellowing of the gums and fever sometimes occur.
These signs can appear very quickly and eventually lead to collapse
and death. Diagnosis of anemia is through clinical signs and blood tests
which indicate a low red cell count. Immune-mediated anemia can
be distinguished from other forms of anemia by the presence of
spherocytes and a specific test called a Coombs' test. Treatment includes the use of corticosteroids to suppress the
immune response to the red cells and where necessary blood transfusions.
The corticosteroids are administered for an initial period of
several weeks while the red cell count is monitored. Once they
have reached an acceptable level the corticosteroids are gradually
reduced. Some animals will require some ongoing monitoring and
therapy. Chemotheraputic drugs such as cyclophosphamide have also
been used to treat non-responsive cases of immune-mediated anemia
with some success. Related sites |