Acquired and Congenital Hemolytic Anemia
1. Suzie A. Noronha, MD* 1. *Division of Pediatric Hematology/Oncology, University of Rochester, Golisano Children's Hospital, Rochester, NY. 1. Pediatricians and other general practitioners may not be aware of the significance of central nervous system disease in children who have sickle cell disease, particularly the more subtle silent infarct. 2. Pediatricians frequently fail to order a reticulocyte count or detect splenomegaly on physical examination before referring a patient with anemia. These findings are critical to diagnosing hemolytic anemia. After completing this article, the reader should be able to: 1. Recognize clinical features of hemolysis, including reticulocytosis and splenomegaly. 2. List the different types of acquired autoimmune hemolytic anemias that can manifest throughout childhood. 3. Understand the role of transfusion in the management of neurologic disease in patients who have sickle cell disease. 4. Review the spectrum of disease of a and b thalassemias. 5. Recognize clinical findings associated with hereditary spherocytosis. 6. Determine when to suspect glucose 6 phosphate dehydrogenase deficiency and how to counsel families on triggers to avoid. Hemolytic anemia (HA) affects a substantial proportion of the pediatric population globally. Many children are hospitalized every year due to sequelae of this heterogeneous disease. Clinicians should be facile in recognizing its presentation. HA may be defined as increased destruction of red blood cells (RBCs) RBCs are cleared from the circulation via extravascular or intravascular mechanisms (Figure) HA can be caused by congenital or acquired RBC abnormalities (Table 1) Figure. Mechanism of extravascular versus intravascular hemolysis. RBC=red blood cell. Courtesy of Jessica Shand, MD. View this table: Table 1. Classification of Common Hemolytic Anemias Extravascular hemolysis is mediated by the reticuloendothelial system (RES) of the spleen and liver. Most HAs, such as warm autoimmune hemolytic anemia (AIHA) sickle cell disease (SCD) and hereditary spherocytosis (HS) are characterized by extravascular hemolysis. The hallmark of extravascular hemolysis is
Pediatrics in Review