Developmental aspects of splenic function in sickle cell diseases

Abstract

Abstract In order to study developmental aspects of splenic function and dysfunction in children with Hb SS disease and other Hb S syndromes, red cells were examined by interference phase–contrast microscopy. In the youngest children studied ( 12% of the red blood cells were pocked, in similarity to what is observed in surgically asplenic individuals. Between 1 and 8 yr of age, many Hb SS children had intermediate numbers of pocked red blood cells, and that suggested hyposplenism. Young children with Hb AS, S-β thalassemia, and S-HPFH were found to have normal splenic function by this technique. Children with Hb SC disease had a moderate degree of splenic dysfunction. This technique correlates with Howell-Jolly body enumeration and 99mTc spleen scans, but it is semiquantitative, and it appears to differentiate the transfusion-reversible “functional” hyposplenism of childhood and the anatomic asplenia secondary to autosplenectomy of later life. Interference phase microscopic enumeration of red cell pocks is a useful and accurate way to assess the onset of splenic dysfunction, which identifies the time of increased susceptibility to overwhelming bacterial infections.