Immune hemolytic anemia
Alternative names
Anemia - immune hemolytic
Definition
Immune hemolytic anemia is
a disorder characterized by anemia due to
premature destruction of red blood cells by the
immune system.
Causes
and risks
Immune hemolytic anemia occurs when antibodies
form against the body’s own red blood cells.
The antibodies may be acquired by blood transfusion,
pregnancy (if the baby’s blood type is different
from the mother’s), as a complication of another
disease, or from a reaction to medications.
If the cause of antibody formation is disease
or medication, it is referred to as secondary
immune hemolytic anemia. The antibodies will
destroy the blood cells because they are recognized
as foreign substances within the body.
The cause may also be unknown, as in idiopathic
autoimmune hemolytic anemia, which accounts
for one-half of all immune hemolytic anemias.
The onset of the disease may be quite rapid
and very serious, or it may remain mild and
not require specific therapy. Risk factors are
related to the causes.
Prevention
Screening for antibodies
in donated blood and in the recipient may prevent
hemolytic anemia related to blood transfusions.
Symptoms
- Fatigue
- Pale color
- Shortness of breath
- Rapid heart rate
- Yellow skin color
- Dark urine
- Enlarged spleen
Signs
and tests
- Positive Coombs’ test, direct or indirect
- Elevated bilirubin levels
- Elevated LDH
- Low serum haptoglobin
- Hemoglobin in the urine
- Elevated absolute reticulocyte count
- Low red blood cell count and hemoglobin
Treatment
Treatment with prednisone
is the first therapy that is tried. If prednisone
does not improve the condition, a splenectomy
(removal of the spleen) may be considered. Immunosuppressive
therapy will be given if the person does not respond
to prednisone and splenectomy.
Blood transfusions are given with caution, if
indicated for severe anemia because of the potential
that blood may not be compatible and it may precipitate
a reaction.
Prognosis
In most people, steroids
or splenectomy control anemia. In others, partial
control of the anemia is usually achieved. |
