REVERSIBLE SPLENIC HYPOFUNCTION IN HYPERTRANSFUSED CHILDREN WITH HOMOZYGOUS SICKLE-CELL DISEASE

Functional hyposplenism, as documented by technetium 99 metastable sul fur colloid spleen scan and increased pocked erythrocyte count (also k nown as a pit count), is well described in children under 2 years of a ge with homozygous sickle cell anemia. We evaluated the clinical cours e and splenic function of 16 patients with sickle cell anemia (ages 3 to 20 years) on a hypertransfusion program for more than 6 months foll owing a cerebrovascular accident. Patients were followed with simultan eous spleen scan and pitted erythrocyte count using direct interferenc e contrast microscopy. Pit counts were taken prior to each transfusion and hemoglobin S level maintained at less than 20%. With the exceptio n of two patients, splenic function was recovered only in those patien ts who were younger than 10 years of age at the time transfusion was i nitiated. There were no serious bacterial infections or other complica tions of sickle cell anemia documented in the hypertransfused group. B ased on our results and the literature review, we conclude that some p atients with sickle cell anemia receiving intensive hypertransfusion t herapy for a cerebrovascular accident recover a normal splenic phagocy tic function. Age and level at which the hemoglobin S is maintained ar e important factors in reestablishing splenic phagocytic function.