Sirdah M, Tarazi I, Al Najjar E, Al Haddad R
Biology Department, Al Azhar University, Gaza, Palestine.
Int J Lab Hematol. 2008 Aug;30(4):324-330. doi: 10.1111/j.1751-553X.2007.00966.x.
Beta-thalassaemia minor and iron deficiency are the most common causes of microcytosis and/or hypochromasia. The present study evaluates the diagnostic reliability of different RBC indices and formulas, as well as our proposed formula, in the differentiation of the beta-thalassaemia minor from iron deficiency in Palestinian population. Complete blood count (CBC) parameters of 2196 certainly diagnosed (1272 beta-thalassaemia minor and 924 iron deficiency) samples were used to evaluate the following indices and formulas: Bessman index (RDW), Mentzer formula (MCV/RBC), England and Fraser formula (MCV - RBC - 5 x Hb- 3.4), Shine and Lal formula (MCV2 x MCH/100), Ehsani formula (MCV-10 x RBC), Srivastava formula (MCH/RBC), Green and King formula (MCV2 x RDW/Hb x 100), red distribution width index RDWI (RDW x MCV/RBC), RDW/RBC, as well as our formula (MCV-RBC -3 x Hb). For each index and formula, the receiver operative characteristic (ROC) curve was constructed to calculate the area under the curve (AUC), in addition, sensitivity, specificity, and likelihood ratios were calculated. No significant differences were reported between our formula, Green-King formula and the RDWI (P > 0.05) in discriminating beta-thalassaemia minor from iron deficiency (AUC = 0.914, 0.909 and 0.907 respectively). However, the three indices and formula showed the highest efficiencies and they were significantly (P < 0.05) better than the others in the discrimination efficiency . It was concluded that our formula, Green-King formula and the RDWI provided the highest reliabilities in differentiating beta-thalassaemia minor from iron deficiency in Palestinian population while Bessman index was poor and ineffective for that purpose.
轻型β地中海贫血和缺铁是小红细胞症和/或低色素血症最常见的病因。本研究评估了不同红细胞指数和公式以及我们提出的公式在巴勒斯坦人群中区分轻型β地中海贫血和缺铁性贫血方面的诊断可靠性。使用2196份确诊样本（1272例轻型β地中海贫血和924例缺铁性贫血）的全血细胞计数（CBC）参数来评估以下指数和公式：贝斯曼指数（RDW）、门泽尔公式（MCV/RBC）、英格兰和弗雷泽公式（MCV - RBC - 5×Hb - 3.4）、施奈德和拉尔公式（MCV²×MCH/100）、埃萨尼公式（MCV - 10×RBC）、斯里瓦斯塔瓦公式（MCH/RBC）、格林和金公式（MCV²×RDW/Hb×100）、红细胞分布宽度指数RDWI（RDW×MCV/RBC）、RDW/RBC以及我们的公式（MCV - RBC - 3×Hb）。对于每个指数和公式，构建了受试者工作特征（ROC）曲线以计算曲线下面积（AUC），此外，还计算了敏感性、特异性和似然比。在区分轻型β地中海贫血和缺铁性贫血方面，我们的公式、格林 - 金公式和RDWI之间未报告显著差异（P>0.05）（AUC分别为0.914、0.909和0.907）。然而，这三个指数和公式显示出最高的效率，并且在区分效率方面显著优于其他指数和公式（P<0.05）。得出的结论是，我们的公式、格林 - 金公式和RDWI在巴勒斯坦人群中区分轻型β地中海贫血和缺铁性贫血方面提供了最高的可靠性，而贝斯曼指数在此目的上较差且无效。
