用1升全血中平均血红蛋白密度鉴别诊断缺铁性贫血和地中海贫血特征

Differential diagnosis between iron deficiency anemia and thalassemia trait based on mean density of hemoglobin in one liter of whole blood

目的探讨1升全血中平均血红蛋白密度(MDHLWB)鉴别诊断缺铁性贫血(IDA)和地中海贫血特征(TT)的临床价值。方法根据物理学"密度"的概念建立了一个新的红细胞参数MDHLWB[MDHLWB=(MCH/MCV×10-3)×RBC计数]。随机选取经血液表型分析诊断的150例IDA和166例TT成年病例,用ROC曲线分析确定MDHLWB鉴别诊断TT和IDA的cutoff值。以分子诊断并结合铁代谢指标分析作为金标准,将MDHLWB和文献报道的IDA和TT鉴别诊断指标用于296例临床小细胞低色素贫血个体的鉴别诊断以评估MDHLWB的临床应用价值。结果 MDHLWB鉴别成年男、女IDA与TT的最佳cutoff值分别为男1.736和女1.493。MDHLWB诊断TT的敏感性(SE)、特异性(SP)、阳性预测值(PPV)、阴性预测值(NPV)、诊断效率(EDF)和约登指数(Youden's index,YI)分别为96.32%、90.98%、92.90%、95.28%、93.92%和0.873,优于其他鉴别诊断指数。结论 MDHLWB可快速、有效地鉴别诊断单纯性的IDA和TT。

Objective To evaluate the clinical application of mean density of hemoglobin in one liter of whole blood （MDHLWB） in the differential diagnosis between iron deficiency anemia （IDA） and thalassemia trait （TT）. Methods Based on the concept of physical density, a new parameter of red blood cell （ RBC）, i. e. , MDHLWB defined as （ MCH/MCV ×10^-3 ） × RBC count, was estab- lished. Two groups of patients, 150 adult patients with IDA and 166 with T＇F diagnosed by the determination of hematological phenotype, were chosen randomly for the investigation. The cut off value of differential diagnosis between IDA and TT was determined by the receiver operating characteristic （ROC） curve of MDHLWB. The clinical application value of MDHLWB was evaluated by the differential diagnosis for 296 patients with small cell hypochromic anemia based on MDHLWB and the markers reported in the references to discriminate IDA and TT, and on the diagnostic gold standards of IDA and TT, such as PCR-based techniques and iron metabolism markers. Results The best cut off values of MDHLWB in differentially diagnosis of IDA and ]T for males and females were 1. 736 and 1. 493, respectively. The sensitivity （SE）, specificity （SP）, positive predictive value （PPV） , negative predictive value （NPV）, efficacy of discriminate function （EDF） and Youden＇s index （YI） for the diagnosis of TT with MDHLWB were 96.32%, 90.98%, 92. 90%, 95.28%, 93.92% and 0. 873, respectively, which was superior to other reported markers. Conclusion The MHDLWB may be a rapid and effective marker for the differential diagnosis between IDA and TT.