Danish Centre for Haemoglobinopathies, Department of Haematology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark.
Department of Immunology and Microbiology, Centre for Medical Parasitology, University of Copenhagen, Copenhagen, Denmark.
Am J Hematol. 2022 Dec;97(12):1520-1528. doi: 10.1002/ajh.26703. Epub 2022 Sep 27.
It is well established that splenic dysfunction occurs in early childhood in sickle cell anemia (SCA), although the determinants and consequences of splenic injury are not fully understood. In this study, we examined spleen size and splenic function in 100 children with SCA aged 0-16 years at King's College Hospital in London. Spleen size was assessed by abdominal ultrasound (US) and splenic function by pitted red blood cells (PIT counts). In our cohort, 5.6% of children aged 6-10 years and 19.4% of children aged 11-16 years had no visible spleen on US (autosplenectomy). Splenomegaly was common in all age groups, with 28% of children overall having larger spleens than the average for their age. Only one child had a PIT count suggesting preserved splenic function. We found no correlation between hemoglobin F levels and spleen size, nor was there any difference in spleen size between children treated with or without hydroxyurea. Although there was a trend toward increased spleen length in children with co-inherited α-thalassemia, this did not reach statistical significance. Finally, we found a strong association between erythrocyte deformability measured with oxygen gradient ektacytometry, spleen size, and PIT counts. In conclusion, our results do not agree with the general perception that most children with SCA undergo autosplenectomy within the first decade of life and indicate that loss of erythrocyte deformability contributes to loss of splenic filtration capacity in SCA, as well as phenotypical variations in spleen size.
众所周知，镰状细胞贫血（SCA）患儿在幼儿期就会出现脾脏功能障碍，尽管脾脏损伤的决定因素和后果尚未完全阐明。在这项研究中，我们检查了 100 名在伦敦国王学院医院就诊的 0-16 岁 SCA 患儿的脾脏大小和脾脏功能。通过腹部超声（US）评估脾脏大小，通过靶形红细胞（PIT 计数）评估脾脏功能。在我们的队列中，6-10 岁儿童中有 5.6%，11-16 岁儿童中有 19.4%的儿童在 US 上看不到脾脏（自发性脾切除）。所有年龄组的脾肿大都很常见，总体有 28%的儿童的脾脏比其年龄的平均脾脏大。只有 1 名儿童的 PIT 计数表明脾脏功能正常。我们发现血红蛋白 F 水平与脾脏大小之间没有相关性，也没有发现羟基脲治疗与未治疗的儿童之间脾脏大小存在差异。尽管在共遗传的α-地中海贫血的儿童中，脾脏长度有增加的趋势，但没有达到统计学意义。最后，我们发现用氧梯度 ektacytometry 测量的红细胞变形性与脾脏大小和 PIT 计数之间存在很强的关联。总之，我们的结果与普遍认为的大多数 SCA 患儿在生命的第一个十年内会发生自发性脾切除的观点不一致，表明红细胞变形性的丧失导致 SCA 中脾滤过能力丧失，以及脾脏大小的表型变化。
