Spleen dysfunction in hemoglobinopathies determined by pitted red cells.

Splenic dysfunction measured by pitted red cells (pit) was studied in hemoglobinopathies (SS-, SC-, and S beta-type thalassemias and CC-type hemoglobinopathy) in relation to age, in steady state, and during certain significant events. Our experience revealed that the pit count rose with age during steady state in most children with SS disease. A marked increase in pit count was noted in patients with CC disease. The pit count in four patients with S beta+ thalassemia remained normal (i.e., less than 3.5%) at all ages. In children with homozygous SS disease tested at the time of pneumococcal sepsis, the pit count was universally elevated. The pit count was in the normal range in one child with SS disease and osteomyelitis but was elevated in all others. All children had normal pit counts (less than 3.5%) at the onset of acute splenic sequestration crisis, and the counts remained normal during transfusion therapy. No correlation was detected between the pit count and the size of the spleen in patients under 1 year of age.