Erythrocytapheresis limits iron accumulation in chronically transfused sickle cell patients

Abstract

Cerebrovascular accidents (CVA) as a complication of sickle cell disease occur most frequently in childhood. Life-long transfusion prevents recurrent stroke, but inevitably leads to iron overload. Although effective chelation exists, many patients are not compliant. Erythrocytapheresis, an automated method of red blood cell exchange, was evaluated as an alternative to control transfusion-related iron load. Eleven patients with sickle cell anemia and a history of stroke were converted from simple transfusion to pheresis. Total time on pheresis for the group averaged 19 months (range 4-36 months). No significant complications occurred with a mean pre-pheresis hemoglobin S (Hb S) level of 44%. Blood utilization increased by an average of 50%. The effect of pheresis on serum ferritin depended on the patient's pre-pheresis ferritin level and chelation regimen. Ferritin levels remained stable for chelated patients with ferritin levels > or = 5,000 ng/ml, but decreased in a chelated patient with a pre-pheresis ferritin level of 4,000 ng/ml. For non-chelated patients with significant pre-pheresis iron load, ferritin levels remained stable. No patient on chelation prior to pheresis was able to discontinue deferoxamine. However, one patient with pre-pheresis ferritin of 500 ng/ml maintained serum ferritin levels < 200 ng/ml for 36 months of pheresis without chelation. Pheresis is more expensive than simple transfusion unless the cost of chelation and organ damage from iron overload are considered. Erythrocytapheresis is a safe method of controlling Hb S levels and limiting or preventing iron load in chronically transfused sickle cell patients.

Prevalence and risk factors for venous thromboembolism in children with sickle cell disease: an administrative database study

“…39 Iron overload, the inevitable consequence of chronic transfusion therapy, may be prevented by erythrocytapheresis. 40,41 We hypothesize that increased use of erythrocytapheresis in children with SCD managed in tertiary care centers in the United States has required increased placement of CVLs and consequently greater thrombosis risk.…”

Stroke in patients with sickle cell disease

“…CTT is complicated by potential risks of alloimmunization [95], infectious disease exposure [96] and iron overload [97], which has prompted a search for alternative therapies. Erythrocytapheresis, automated red blood cell exchange, can limit iron loading and obviate the need for chelation therapy, but is associated with a two-to three-fold greater donor exposure and requires adequate venous access [98][99][100][101]. Strategies that relax transfusion goals after several years to maintain a hemoglobin S under 50% have reduced the amount of blood products required and the resulting iron load without an increased risk of infarctive stroke; however, the long-term effect on progression of vasculopathy and silent infarcts remains to be studied [102,103].…”

Transfusional iron overload in children with sickle cell anemia on chronic transfusion therapy for secondary stroke prevention

“…The finding of the lowest iron burden in children receiving erythrocytapheresis is not surprising, given that this method is associated with a reduction in net red cell loading [9,10]. Overall treatment costs also are lowered if chelation therapy can be avoided [20], further supporting the early use of erythrocytapheresis for long-term transfusion therapy in SCA when feasible. The finding of the highest iron loading in the subjects receiving partial exchange transfusion is unexpected.…”