Reversible splenic hypofunction in hypertransfused children with homozygous sickle cell disease

Area of Science:

• Hematology
• Pediatrics
• Immunology

Background:

• Functional hyposplenism is common in young children with homozygous sickle cell anemia.
• Hyposplenism is diagnosed via spleen scans and increased pitted erythrocyte counts.
• Cerebrovascular accidents (CVAs) are a serious complication in sickle cell anemia.

Purpose of the Study:

• To evaluate splenic function recovery in sickle cell anemia patients on a hypertransfusion program after a CVA.
• To determine factors influencing splenic function recovery in this patient group.

Main Methods:

• Assessed 16 sickle cell anemia patients (ages 3-20) on a hypertransfusion program (>6 months post-CVA).
• Utilized simultaneous spleen scans and pitted erythrocyte counts (pit counts) to monitor splenic function.
• Maintained hemoglobin S levels below 20% via regular transfusions.

Main Results:

• Splenic function recovery was observed in most patients younger than 10 years at the start of transfusion therapy.
• Two patients did not show recovery of splenic function.
• No serious bacterial infections or other sickle cell anemia complications occurred in the hypertransfused group.

Conclusions:

• Intensive hypertransfusion therapy can lead to recovery of splenic phagocytic function in some sickle cell anemia patients post-CVA.
• Patient age at initiation of therapy and the maintained hemoglobin S level are critical factors for splenic function recovery.