Hilliard L M, Williams B F, Lounsbury A E, Howard T H
Department of Pediatrics, University of Alabama at Birmingham, USA.
Am J Hematol. 1998 Sep;59(1):28-35. doi: 10.1002/(sici)1096-8652(199809)59:1<28::aid-ajh6>3.0.co;2-1.
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.
脑血管意外（CVA）作为镰状细胞病的一种并发症，最常发生于儿童期。终身输血可预防复发性中风，但不可避免地会导致铁过载。尽管有有效的螯合疗法，但许多患者并不依从。红细胞单采术是一种红细胞置换的自动化方法，被评估为控制输血相关铁负荷的一种替代方法。11例有中风病史的镰状细胞贫血患者从单纯输血转为单采术。该组患者单采术的总时间平均为19个月（范围4 - 36个月）。在单采术前平均血红蛋白S（Hb S）水平为44%的情况下，未发生明显并发症。血液利用率平均提高了50%。单采术对血清铁蛋白的影响取决于患者单采术前的铁蛋白水平和螯合方案。对于铁蛋白水平≥5000 ng/ml的螯合患者，铁蛋白水平保持稳定，但对于单采术前铁蛋白水平为4000 ng/ml的螯合患者，铁蛋白水平下降。对于单采术前有明显铁负荷的非螯合患者，铁蛋白水平保持稳定。在单采术前接受螯合治疗的患者中，没有一人能够停用去铁胺。然而，一名单采术前铁蛋白为500 ng/ml的患者在36个月的单采术期间未进行螯合，血清铁蛋白水平维持在<200 ng/ml。除非考虑到螯合成本和铁过载导致的器官损害，否则单采术比单纯输血更昂贵。红细胞单采术是控制慢性输血的镰状细胞病患者Hb S水平和限制或预防铁负荷的一种安全方法。
