Department of Pediatrics, Kuwait University, Kuwait, Kuwait.
Acta Haematol. 2010;123(3):135-9. doi: 10.1159/000276998. Epub 2010 Jan 21.
Hemoglobin (Hb) SD-Los Angeles compound heterozygotes usually have a severe clinical course although the effect of an elevated Hb F on the clinical phenotype has not been reported previously. We describe 5 Kuwaiti children with Hb SD associated with Hb F levels >20%. They all presented with sickling-related symptoms by < or =2 years of age and have been followed for 3-15 years. All had severe clinical courses marked by varying degrees of splenic sequestration crises, acute chest syndrome, vaso-occlusive crises, osteomyelitis and avascular necrosis of the femoral head. This pattern is in contrast with the usually mild presentation in Kuwaiti Hb SS patients with elevated Hb F. It therefore appears that Hb F does not ameliorate the clinical phenotype in Hb SD-Los Angeles. The reasons for this are not quite clear.
血红蛋白（Hb）SD-Los Angeles 复合杂合子通常具有严重的临床病程，尽管之前尚未报道升高的 Hb F 对临床表型的影响。我们描述了 5 名科威特儿童，他们的 Hb SD 与 Hb F 水平>20%相关。他们都在<或=2 岁时出现与镰状细胞相关的症状，并已随访 3-15 年。所有人都有严重的临床病程，表现为不同程度的脾隔离危机、急性胸部综合征、血管阻塞危机、骨髓炎和股骨头缺血性坏死。这种模式与科威特 Hb SS 患者中升高的 Hb F 通常表现出的轻度表现形成对比。因此，Hb F 似乎不能改善 Hb SD-Los Angeles 的临床表型。其原因尚不清楚。
