Alauddin H, Langa M, Mohd Yusoff M, Raja Sabudin R Z A, Ithnin A, Abdul Razak N F, Sardi N H, Hussin N H
UKM Medical Center, Faculty of Medicine, Department of Pathology, Universiti Kebangsaan Malaysia Medical Center, Jalan Yaacob Latif, Bandar Tun Razak, Cheras 56000, Kuala Lumpur, Malaysia.
Malays J Pathol. 2017 Apr;39(1):17-23.
Haemoglobin Bart's (Hb Bart's) level is associated with α-thalassaemia traits in neonates, enabling early diagnosis of α-thalassaemia. The study aimed to detect and quantify the Hb Bart's using Cord Blood (CB) and CE Neonat Fast Hb (NF) progammes on fresh and dried blood spot (DBS) specimen respectively by capillary electrophoresis (CE).
Capillarys Hemoglobin (E) Kit (for CB) and Capillarys Neonat Hb Kit (for NF) were used to detect and quantify Hb Bart's by CE in fresh cord blood and dried blood spot (DBS) specimens respectively. High performance liquid chromatography (HPLC) using the β-Thal Short Programme was also performed concurrently with CE analysis. Confirmation was obtained by multiplex ARMS Gap PCR.
This study was performed on 600 neonates. 32/600 (5.3%) samples showed presence of Hb Bart's peak using the NF programme while 33/600 (5.5%) were positive with CB programme and HPLC methods. The range of Hb Bart's using NF programme and CB programme were (0.5-4.1%) and (0.5-7.1%), respectively. Molecular analysis confirmed all positive samples possessed α-thalassaemia genetic mutations, with 23/33 cases being αα/--, four -α/-α, two αα/-α and three αα/αα. Fifty Hb Bart's negative samples were randomly tested for α-genotypes, three were also found to be positive for α-globin gene mutations. Thus, resulting in sensitivity of 91.7% and 88.9% and specificity of 100% for the Capillarys Cord Blood programme and Capillarys Neonat Fast programme respectively.
Both CE programmes using fresh or dried cord blood were useful as a screening tool for α-thalassaemia in newborns. All methods show the same specificity (100%) with variable, but acceptable sensitivities in the detection of Hb Bart.
血红蛋白巴特氏（Hb Bart's）水平与新生儿α地中海贫血特征相关，有助于α地中海贫血的早期诊断。本研究旨在分别通过毛细管电泳（CE），使用脐血（CB）和CE新生儿快速血红蛋白（NF）程序，对新鲜和干血斑（DBS）标本中的Hb Bart's进行检测和定量。
分别使用毛细管血红蛋白（E）试剂盒（用于CB）和毛细管新生儿血红蛋白试剂盒（用于NF），通过CE对新鲜脐血和干血斑（DBS）标本中的Hb Bart's进行检测和定量。同时，使用β-地中海贫血短程序进行高效液相色谱（HPLC）分析。通过多重ARMS缺口PCR进行确认。
本研究对600名新生儿进行了检测。使用NF程序时，32/600（5.3%）的样本显示存在Hb Bart's峰，而使用CB程序和HPLC方法时，33/600（5.5%）为阳性。使用NF程序和CB程序时，Hb Bart's的范围分别为（0.5 - 4.1%）和（0.5 - 7.1%）。分子分析证实所有阳性样本均具有α地中海贫血基因突变，其中23/33例为αα/--，4例为-α/-α，2例为αα/-α，3例为αα/αα。随机对50例Hb Bart's阴性样本进行α基因型检测，发现其中3例α珠蛋白基因突变也呈阳性。因此，毛细管脐血程序和毛细管新生儿快速程序的灵敏度分别为91.7%和88.9%，特异性均为100%。
使用新鲜或干脐血的两种CE程序均可用作新生儿α地中海贫血的筛查工具。所有方法在检测Hb Bart时均显示相同的特异性（100%），灵敏度虽有差异，但均可接受。
