Traumatic hemolytic anemiaIntroduction: When
there are multiple injuries to a person from a motor vehicle accident or from
an assault, red blood cells can get damaged from the transmitted forces and blood
vessel compression. On a microscopic level the hematologist can see red blood
cell fragments with odd shapes in a blood smear. The hematologist will term these
with names such as helmet shapes, triangles etc. Medically they are also known
as “schistocytes”. The bone marrow, liver and spleen are lined with special
cells, called reticulocytes that will remove these red blood cell fragments. The
spleen and the liver are particularly well equipped to do this cleansing of the
blood. If the trauma stops and was limited, a steady state is reintroduced by
the release of reticulocytes from the bone marrow that is the last precursor of
new red blood cells. Traumatic hemolytic anemia can occur also in other clinical
situations such as with calcific aortic stenosis, with malfunctioning artificial
aortic valves, with repetitive foot striking from marching (called “march hemoglobinuria”).
Other such conditions are extremely high blood pressure (malignant hypertension),
thrombotic thrombocytopenic purpura, disseminated intravascular coagulation (DIC),
disseminated cancer, hemolytic-uremic syndrome, lupus erythematosus and polyarteritis
nodosa that can also lead to traumatic hemolytic anemia because of damaged small
blood vessels. Diagnostic tests: The blood tests
show the hallmarks of a hemolytic anemia with a low mean corpuscular volume (MCV),
but a high distributions width due to the fragments of red blood cells in the
blood. Iron deficiency occurs, when there has been a chronic hemosiderinuria (loss
of iron through urine). Treatment: Treatment is
directed at the underlying cause. Iron loss can be remedied with iron replacement
therapy for a period of time. |
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