Pediatric emergency medicine trisk 2195 2195

• Bone marrow transplantation–associated microangiopathy

FIGURE 93.2 Approach to evaluation of hemolytic anemia.

Examination of the peripheral blood smear is helpful in diagnosing subsets of
nonimmune hemolytic anemia especially in the acute care setting when the results of
disease-specific testing such as osmotic fragility, hemoglobin electrophoresis, or G6PD
activity will not be available. Certain patterns of red cell morphology can support a
diagnosis of hemoglobinopathy or enzymopathy. The presence of RBC fragments
(schistocytes) on the peripheral smear suggests mechanical damage to the erythrocyte. If
the diagnosis is uncertain, a pretransfusion blood sample should be saved for additional
testing such as the measurement of specific enzyme levels or hemoglobin
electrophoresis. The diagnosis of microangiopathic processes such as hemolytic uremic
syndrome (HUS) and thrombotic thrombocytopenic purpura (TTP) is important and
should be considered in patients with diarrhea, and in the presence of acute kidney
injury, thrombocytopenia, fever, and neurologic changes. Disseminated intravascular
coagulopathy (DIC) occurs in the context of systemic illness, including sepsis, trauma,
or malignancy. If considering any microangiopathic process, evaluation should also
include a coagulation panel.
Management
AIHA. Prompt initiation of therapy for AIHA is necessary to stabilize the rate of
hemolysis. Hospitalization for careful observation and treatment is usually necessary;