Microangiopathic Hemolytic Anemia
GENERAL PRINCIPLES
Definition
Microangiopathic hemolytic anemia (MAHA) is a syndrome of traumatic intravascular hemolysis causing fragmentation of the RBCs that are seen on peripheral blood smear (schistocytes).
It is not a specific diagnosis but suggests a limited differential diagnosis.Etiology
Possible causes of MAHA include mechanical heart valve, malignant hypertension, vasculitis, adenocarcinoma, preeclampsia/eclampsia, disseminated intravascular coagulation (DIC), thrombotic thrombocytopenic purpura (TTP), and hemolytic uremic syndrome (HUS)#8725;atypical HUS (see Chapter 20, Disorders of Hemostasis and Thrombosis, for a discussion of DIC, TTP, and HUS/atypical HUS).
DIAGNOSIS
MAHA is established by confirming the presence of hemolysis with laboratory data (LDH, haptoglobin, indirect bilirubin) and identifying RBC fragments (schistocytes) on peripheral blood smear. Thrombocytopenia is also common.
TREATMENT
The treatment depends on the underlying etiology of microangiopathy (see Chapter 20, Disorders of Hemostasis and Thrombosis).