Institute of Child Health, College of Medicine, University of Ibadan, Ibadan, Nigeria.
Acta Trop. 2012 Aug;123(2):72-7. doi: 10.1016/j.actatropica.2012.03.013. Epub 2012 Apr 5.
In regions of high Plasmodium falciparum malaria endemicity, certain erythrocyte polymorphisms confer resistance to severe disease. In this study, we evaluate the role of the sickle cell trait (HbS) and ABO blood groups in the clinical manifestations of childhood malaria in Southwest Nigeria. The subjects comprised 3100 children (53% males, median age 39 months), including 1400 children with uncomplicated malaria, 1000 children with asymptomatic malaria and 700 with severe malaria. Haemoglobin (Hb) types were determined using electrophoresis and serum agglutination techniques were used to determine ABO blood groups. Blood group O was the commonest ABO blood group (47.7%) in the study population, the others were A (22.5%), B (25.2%) and AB (4.6%). The frequencies of the HbAS and HbAC were 14.4% and 5.8%, respectively. In regression models adjusting for age, gender, parasite density and blood group, HbAS was associated with a reduced risk of severe malaria OR=0.46 (CI(95%): 0.273-0.773). Among severe malaria subjects, HbAS was associated with significantly lower parasite densities. The protective effect of blood group O was demonstrated with a decreased risk of severe malaria OR=0.743 (CI(95%): 0.566-0.976) after adjusting for age, gender and parasite density and Hb genotype. Blood group B was associated with increased risk of severe malaria OR=1.638 (CI(95%): 1.128-2.380) after adjusting for age, gender, packed cell volume, parasite density and Hb genotype. We have confirmed from this large study of Nigerian children the major protective effective of the sickle cell heterozygous state against both cerebral malaria and severe malarial anaemia. We also show that the B blood group is associated with an increased risk of severe malaria. In conclusion, the sickle cell haemoglobin type and ABO groups modulate the risk of severe malaria in Nigerian children.
在恶性疟原虫高度流行的地区，某些红细胞多态性赋予了对严重疾病的抵抗力。在这项研究中，我们评估了镰状细胞特征（HbS）和 ABO 血型在尼日利亚西南部儿童疟疾临床症状中的作用。研究对象包括 3100 名儿童（53%为男性，中位数年龄为 39 个月），包括 1400 名患有无并发症疟疾的儿童、1000 名无症状疟疾的儿童和 700 名患有严重疟疾的儿童。使用电泳法确定血红蛋白（Hb）类型，并使用血清凝集技术确定 ABO 血型。研究人群中最常见的 ABO 血型是 O 型（47.7%），其次是 A 型（22.5%）、B 型（25.2%）和 AB 型（4.6%）。HbAS 和 HbAC 的频率分别为 14.4%和 5.8%。在调整年龄、性别、寄生虫密度和血型的回归模型中，HbAS 与严重疟疾的风险降低相关，OR=0.46（95%CI：0.273-0.773）。在严重疟疾患者中，HbAS 与寄生虫密度显著降低相关。在调整年龄、性别和寄生虫密度以及 Hb 基因型后，O 型血显示出降低严重疟疾风险的保护作用，OR=0.743（95%CI：0.566-0.976）。在调整年龄、性别、红细胞压积、寄生虫密度和 Hb 基因型后，B 型血与严重疟疾的风险增加相关，OR=1.638（95%CI：1.128-2.380）。我们从这项对尼日利亚儿童的大型研究中证实，镰状细胞杂合状态对脑型疟疾和严重疟疾性贫血都具有主要的保护作用。我们还表明，B 型血与严重疟疾的风险增加有关。总之，镰状细胞血红蛋白类型和 ABO 血型组调节尼日利亚儿童严重疟疾的风险。
