孕产妇358名产前地中海贫血基因筛查和诊断分析

目的分析孕产妇产前地中海贫血的基因筛查和诊断情况。方法应用全血细胞计数和血红蛋白电泳技术对358名孕妇进行产前筛查,分析红细胞平均体积(MCV)、红细胞平均血红蛋白含量(MCH)值以及血红蛋白电泳异常区带;应用裂口-聚合酶链式反应(Gap-PCR)和聚合酶链式反应(PCR)结合反向点杂交技术进行地中海贫血的基因诊断。结果 358名孕产妇中仅发现3例血红蛋白病[2例血红蛋白K(HbK)和1例血红蛋白D(HbD)]。结论 Gap-PCR和PCR结合反向点杂交技术在诊断地中海贫血中存在一定的漏检风险,该技术需与DNA测序配合使用才能提高诊断的准确度。     

广西地区不同地中海贫血类型G6PD酶活性水平初步研究

目的了解广西地区不同地中海贫血类型患者的葡萄糖-6-磷酸脱氢酶(G6PD)酶活性水平,探讨其与地中海贫血的关联性。方法对经过地中海贫血基因分析确诊阴性的113名健康人群和248例不同地中海贫血类型的患者进行G6PD酶活性检测,并对结果进行统计学分析。结果健康人群组的G6PD酶活性水平为(6.76±2.28)U/g Hb,α地中海贫血为(9.00±3.67)U/g Hb,β地中海贫血为(10.98±6.25)U/g Hb,αβ复合型地中海贫血为(9.09±2.96)U/g Hb,与健康人群组比较差异均有统计学意义(P0.05)。α地中海贫血中静止型、轻型和中间型的G6PD酶活性水平分别为(6.67±1.65)、(8.89±2.12)和(12.7±5.44)U/g Hb,β地中海贫血中轻型和中间型/重型的G6PD酶活性水平分别为(9.68±3.71)U/g Hb和(18.43±10.71)U/g Hb,α和β地中海贫血组内不同类型之间的G6PD酶活性水平比较差异有统计学意义(P0.05)。结论不同地中海贫血类型患者的G6PD酶活性水平不一样,贫血程度越重G6PD酶活性越高。     

湖北省人群G—6—PD活性抽样调查

在湖北省６个县市抽样调查人群葡萄糖－６－磷酸脱氢酶（Ｇ－６－ＰＤ）缺乏情况，以例为疟防工作使用伯喹提供资料。共调查１６３１例中小学生，有显著缺乏，轻度缺乏及可疑缺乏者３３例，占调查总数的２．０２％。Ｇ－６－ＰＤ缺乏症在性别和民族间有明显差异。     

MCV、EOFT及Hb电泳联合检测在地中海贫血筛查中的价值

目的探讨平均红细胞体积（MCV）、红细胞脆性试验（EOFT）和Hb电泳联合检测在地中海贫血（地贫）筛查中的价值。方法对经分子生物学技术确诊的195例地贫患者（地贫组）和109例非地贫者（对照组）同时进行MCV、EoFr和Hb电泳测定,并对两组三种方法单项检测阳性率及联合检测的灵敏度（Se）、特异度（Sp）等作相关统计学分析。结果地贫组三种方法单项检测阳性率均显著高于对照组（P〈0．001）;除MCV和Eovr平行联合检测的Se与MCV单项检测的Se无显著差异外,其他平行联合检测的Se均显著高于各单项检测的Se,系列联合检测的Sp均显著高于各单项检测的Sp（P均〈0．05）。结论MCV、EOFT及Hb电泳联合检测可降低地贫漏检率,提高诊断的Se与Sp。     

广西地中海贫血不同基因型血常规参数MCV MCH及血红蛋白电泳检测结果的差异分析

目的通过对广西地区几种常见地贫基因型的血常规参数,即平均红细胞体积(mean corpuscular volume,MCV)、平均红细胞血红蛋白量(mean corpuscular hemoglobin,MCH)和血红蛋白电泳检测结果进行对比,探索数值差异与基因型之间的相关性。方法采用Gap-PCR法进行α地贫(缺失型)基因检测,采用反向斑点杂交法进行α地贫(非缺失型)和β地贫的基因检测;使用全自动血细胞分析仪进行血细胞分析;使用全自动毛细管电泳仪测定血红蛋白各项指标。结果研究发现静止型α地贫中α~(QS)α/αα基因型的MCV、MCH最低;轻型α地贫中--~(SEA)/αα基因型血液学表现最为严重,差异有统计学意义(P0.05)。轻型α地贫和中间型α地贫Hb A2减少,而轻型β地贫及复合型地贫Hb A2增加,差异有统计学意义(P0.05)。Hb CS带仅出现在α~(CS)α/αα、-α3.7/α~(CS)α、--~(SEA)/α~(CS)α等含有CS点突变的基因型中,但α~(CS)α/ααβ~(CDs41-42)/β~N却未表现出Hb CS带,差异有统计学意义(P0.05)。在中间型α地贫(血红蛋白H病)中,--SEA/α~(CS)α、--~(SEA)/-α4.2和--~(SEA)/-α3.7三种基因型血红蛋白电泳结果均呈现不同程度的Hb-H带,而--SEA/αWSα中却并未发现血红蛋白电泳Hb-H带,差异有统计学意义(P0.05)。复合型地贫(轻型α+轻型β)同复合型地贫(静止型α+轻型β)相比,其贫血程度较轻,差异有统计学意义(P0.05)。结论 MCV、MCH和血红蛋白电泳的结果与基因表型有一定的相关性,对于临床医师在进行地贫遗传咨询时有很好的指导意义,对于地贫防控也具有重要意义。     

老年地中海贫血临床血液学特征及铁负荷

目的 探讨老年地中海贫血患者和非地中海贫血患者血液学特征和铁负荷的差异。方法 选取149例初次诊断地中海贫血患者为地中海贫血组,非地中海贫血患者152例为对照组,检测患者外周血红细胞数量(RBC)、血红蛋白(HB)、红细胞平均体积(MCV)、平均红细胞血红蛋白量(MCH)及血清铁蛋白(SF),做回顾性分析,多组间比较采用单因素方差分析,两样本的铁过载比较采用四格表资料的χ²检验。结果 地中海贫血组RBC、HB均较对照组高,有显著差异(P<0.01),地中海贫血组MCV、MCH均较对照组明显降低(P<0.01);铁过载率地中海贫血组与非地中海贫血组有显著差异(P<0.01);地中海贫血组与对照组SF有显著差异(P<0.01);地中海贫血组中SF以年龄分组无统计学差异(P>0.05)。结论 老年地中海贫血患者有更高的铁过载风险,应多关注无症状的轻型及中间地中海贫血患者,随着年龄增长越来越多的患者将需要治疗,应预防并避免出现与疾病相关并发症。     

恶性克隆性疾病伴红细胞G6PD缺陷二例

例1，男，53岁，以头晕、乏力1年，畏冷、发热6天为主诉，于1984年9月入院。体检：神志清楚，无贫血外观，巩膜无黄染，心脏无异常，右肺呼吸音减低，可闻及少许湿性罗音。肝肋下未及，脾助下1cm可及，神经系统无异常。实验室检查：血常规：Hb170g／L，WBC1．1×109／L，中性分     

NBT纸片定性法与G6PD/6PGD比值法在大样本G6PD缺陷症筛查中的联合应用

目的：探讨联合应用葡萄糖-6-磷酸脱氢酶（G6PD）四氮唑蓝（NBT）纸片定性法与G6PD／6PGD比值定量法在大样本筛查中的可行性。方法：用NBT纸片定性法对501例贵州省江口县土家族、525例从江县侗族、586例荔波县瑶族共1612例成人进行定性初筛，再用G6PD／6PGD比值法对初筛阳性样本定量复查。结果：NBT纸片定性法共初筛出G6PD缺陷患者129例，G6PD／G6PD比值法确诊G6PD缺陷123例，2种方法的符合率高达95．35％。结论：对大样本G6PD缺陷症的筛查，先用NBT纸片定性法进行初筛，再用G6PD／6PGD比值法复查确诊，2法联合应用可以提高G6PD缺陷症检出率和节约大量经费和时间。     

全自动血红蛋白电泳在地中海贫血筛查中的应用效果

目的探讨全自动血红蛋白电泳在地中海贫血筛查中的应用效果。方法选取2016年1月—2017年6月于广州市番禺区何贤纪念医院进行血液检查的患者1 206例。所有患者行血液检查,抽取血液样本1 206份,行全自动血红蛋白电泳检测。观察所有患者地中海贫血分型,比较基因筛查与全自动血红蛋白电泳检测地中海贫血的阳性率。结果α地中海贫血患者62例;β地中海贫血患者40例。基因筛查与全自动血红蛋白电泳检测的地中海贫血阳性率比较,差异无统计学意义(P>0.05)。结论全自动血红蛋白电泳在地中海贫血筛查中的应用效果较好。     

中间型地中海贫血患者血红蛋白和红细胞压积的季节性变化

目的:证实中间型地中海贫血(地贫)患者是否存在血红蛋白(Hb)水平和红细胞压积(Hct)的季节性变化。方法:于2005年5月至2006年3月逢单月应用美国产CellDyn1700和日本产Symex820血细胞计数仪对中间型α地贫和中间型β地贫进行血细胞分析,按要求完成6次取样中间型地贫40例,男26例,女14例,健康对照11例,男7例,女4例。分析Hb水平和Hct值与月份的关系和与当地月平均气温的相关性。结果:40例患者Hb水平和Hct的平均值与月份呈非线性相关,Hb水平和Hct最低平均值出现在7月份,差异有统计学意义(P<0.01),同期当地月平均气温与Hb水平和Hct平均值间的Pearson相关系数分别为-0.902(P<0.05)和-0.878(P<0.05),呈显著负相关。对照组也呈现相同的负相关。结论:中间型地贫患者与健康对照均存在Hb水平和Hct的季节性变化。     

Using the fluorescence spot test for neonatal screening of G6PD deficiency

To establish the neonatal screening method of glucose-6 phosphate dehydrogenase (G6PD) deficiency, G6PD activity was measured using the fluorescence spot test (FST) using dried blood samples on filter paper. The G6PD/6PGD rate test of venous blood samples was further performed for confirmation. The positive G6PD deficiency rate was 4.2% and its detection rates were 3.7% for all neonates and 5.2% only for male newborns when FST was used for neonatal screening. Conformation rates by use of G6PD/ 6PGD ratio test for G6PD deficiency were 86.8% and 100% particularly in the severely deficient groups. Both sensitivity and specificity were very high in the severely deficient groups. FST can be used in neonatal screening of G6PD deficiency because of its high accuracy, applicability, and simplicity. Moreover, a high volume of dried blood samples on filter paper can be tested quickly. It is very favorable to diagnose and treat G6PD deficiency early in high incidence districts.     

G6PD Viangchan and G6PD Mediterranean are the main variants in G6PD deficiency in the Malay population of Malaysia

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-linked red blood cell enzymopathy common in malaria endemic areas. Individuals affected by this disease show a wide variety of clinical signs of acute hemolytic anemia. Mutations of the G6PD gene in the Malay population with G6PD deficiency in Kelantan, a state in North East Malaysia were studied. Ninety-three individuals with G6PD deficiency were subjected to mutation analysis of the G6PD gene using polymerase chain reaction based techniques of multiplex PCR. Of the ninety-three DNA samples studied, molecular defects were identified in 80 cases (86%). Variants were heterogeneous - 28.7% were found to have a G to A nucleotide change at nucleotide 871 of the G6PD gene (G871A), corresponding to G6PD Viangchan. The other major mutations were G6PD Mediterranean, G6PD Vanua Lava, G6PD Coimbra, G6PD Kaiping, G6PD Orissa, G6PD Mahidol, G6PD Canton and G6PD Chatham. These results showed that there are heterogeneous mutations of the G6PD gene associated with G6PD deficiency and that G6PD Viangchan and G6PD Mediterranean account for the main variants in G6PD deficiency among the Malay population in Malaysia.     

G6PD deficiency: the genotype-phenotype association

Deficiency of glucose-6-phosphate dehydrogenase is a very common X-linked genetic disorder though most deficient people are asymptomatic. A number of different G6PD variants have reached polymorphic frequencies in different parts of the world due to the relative protection they confer against malaria infection. People, usually males, with deficient alleles are susceptible to neonatal jaundice, and acute hemolytic anemia, usually during infection, after treatment with certain drugs or after eating fava beans. Very rarely de novo mutations can arise causing the more severe condition of chronic nonspherocytic hemolytic anemia. Altogether 160 different mutations have been described. The majority of mutations cause red cell enzyme deficiency by decreasing enzyme stability. The polymorphic mutations affect amino acid residues throughout the enzyme and decrease the stability of the enzyme in the red cell, possibly by disturbing protein folding. The severe mutations mostly affect residues at the dimer interface or those that interact with a structural NADP molecule that stabilizes the enzyme.     

The prevalence of G6PD deficiency in blood transfusion recipients

G6PD deficiency is the most common metabolic disorder of red blood cells, involving about 35 million people worldwide. Tropical and subtropical regions in the eastern hemisphere have the highest prevalence, up to 35% in some areas. The prevalence varies in different parts of the world. According to WHO, there is a 10-14.9% prevalence of G6PD deficiency in Iran. With this high prevalence, blood products are not still checked for G6PD deficiency. So, they may be used for transfusion in neonates with jaundice or for patients using oxidants. In this cross-sectional study, we have observed the effects of using this kind of blood in patients receiving blood in the Pediatric and Neonatology Departments of Imam Sajjad's Hospital in Yasuj. Samples were taken from 261 blood bags used for transfusion or exchange, and examined by spot fluorescence for G6PD deficiency. All of the patients receiving blood were examined for hemoglobin, hematocrit, and bilirubin before and after transfusion. They were also examined for hemoglobinuria, factors involved in hemolysis due to G6PD deficiency, and oxidants. Results: From the 261 blood transfusions, 37(14.17%) blood bags had G6PD deficiency. About 81% of these transfusion recipients had at least one risk factor for hemolysis. The complications associated with receiving these red cells were: insufficient rise in hemoglobin (55.9%), hemoglobinuria (35.3%) and rise in bilirubin (8.8%), which were significantly higher than the control group. Conclusion: Considering the high prevalence and complications of transfusing G6PD deficient blood to high risk patients, it is recommended that in the form used for requesting blood products, there should be a place for checking G6PD enzyme so that the physician requesting blood could request the test to be done, depending on the risk factors.     

The prevalence of G6PD deficiency in blood transfusion recipients

G6PD deficiency is the most common metabolic disorder of red blood cells, involving about 35 million people worldwide. Tropical and subtropical regions in the eastern hemisphere have the highest prevalence, up to 35% in some areas. The prevalence varies in different parts of the world. According to WHO, there is a 10–14.9% prevalence of G6PD deficiency in Iran. With this high prevalence, blood products are not still checked for G6PD deficiency. So, they may be used for transfusion in neonates with jaundice or for patients using oxidants.

In this cross-sectional study, we have observed the effects of using this kind of blood in patients receiving blood in the Pediatric and Neonatology Departments of Imam Sajjad's Hospital in Yasuj. Samples were taken from 261 blood bags used for transfusion or exchange, and examined by spot fluorescence for G6PD deficiency. All of the patients receiving blood were examined for hemoglobin, hematocrit, and bilirubin before and after transfusion. They were also examined for hemoglobinuria, factors involved in hemolysis due to G6PD deficiency, and oxidants.

Results: From the 261 blood transfusions, 37 (14.17%) blood bags had G6PD deficiency. About 81 % of these transfusion recipients had at least one risk factor for hemolysis. The complications associated with receiving these red cells were: insufficient rise in hemoglobin (55.9%), hemoglobinuria (35.3%) and rise in bilirubin (8.8%), which were significantly higher than the control group.

Conclusion: Considering the high prevalence and complications of transfusing G6PD deficient blood to high risk patients, it is recommended that in the form used for requesting blood products, there should be a place for checking G6PD enzyme so that the physician requesting blood could request the test to be done, depending on the risk factors.     

Molecular basis of G6PD deficiency in India

G6PD deficiency has been reported from India more than 30 years ago and about 13 variants have been characterized biochemically. Here, we report the results of an epidemiological study investigating G6PD deficiency and the mutations among 14 heterogenous populations of India. Of the 3166 males tested, 332 (10.5%) were found to be G6PD-deficient and the prevalence rate varied from 5.7% to 27.9% in the different population groups. Molecular characterization revealed that G6PD Mediterranean (563 C-->T) was the commonest (60.4%) deficient variant followed by G6PD Kerala-Kalyan (949 G-->A; 24.5%) and G6PD Orissa (131 C-->G; 13.3%). G6PD Mediterranean had a more widespread distribution as compared to G6PD Kerala-Kalyan and G6PD Orissa and was associated with both 1311 C and 1311 T polymorhism. G6PD Mediterranean was found to have significantly lower red cell enzyme activity and more severe clinical manifestations than the other two. G6PD Chatham (1003 G-->A) with undetected red cell enzyme activity and G6PD Insuli (989 G-->A) with normal G6PD activity were very rare in the Indian population. The absence of a large number of mutations causing G6PD deficiency points to the fact that the genetic diversity of these populations is considerably lowered than expected.