Differences in the distribution of hemoglobin variants according to the geographic regions in a Colombian population

ABSTRACT Introduction: Colombia has been subject to intense genetic and cultural currents due to its geographical location. Hemoglobinopathies are the most common recessive diseases found worldwide and represent an important public health problem, according to the region and ancestry of each country. Objectives: To evaluate the frequency of hemoglobin variants according to the geographical region in a population group adjusted to sex and age in Colombia. Methods: This was a descriptive retrospective study of hemoglobin variants performed by electrophoresis in patients treated at and/or referred to specialized care institutions in Bogota, Colombia between January 2009 and December 2020. Results: A total of 2,224 results were analyzed, 48.4% male and 51.5% female; 63.3% of patients were without alterations, 14.3% presented with thalassemia, 17.3%, HbS, 2.3%, HbS/C, 1.8%, HbC, 0.5%, HbE and 0.5% persistent HbF, with HbS being more prevalent in males (p = 0.005). When assessing the geographical regions of Colombia, a higher prevalence of HbS was found in the Pacific (p = 0.005) and Caribbean regions, while Thalassemia and HbS were more prevalent in the Andean and Orinoquia regions, and it was rare to find any hemoglobinopathies (p = 0.0001) in the Amazonian region. Conclusions: The main hemoglobinopathies found in Colombia are HbS, predominantly in males, and Thalassemia. The distribution of hemoglobinopathies in different geographical regions of Colombia is influenced by ancestry.

Causes of Abnormal Hemoglobin Electrophoresis / 中国实验血液学杂志

OBJECTIVE@#To investigate the possible causes of abnormal hemoglobin electrophoresis results.@*METHODS@#The hemoglobin electrophoresis results of 5 696 patients in the First Affiliated Hospital of Chengdu Medical College from September 2018 to July 2021 were collected, and the abnormal results and clinical significance were analyzed.@*RESULTS@#The results of 486 patients (accounting for 8.53%) were abnormal, of which 300 cases had increased HbA2, 135 cases had decreased HbA2, 44 cases had increased F alone, and 7 cases had abnormal hemoglobin bands. Among the 486 patients, 246 patients were thalassemia gene positive (the positive rate was 50.62%), including 29 cases of α thalassemia, 208 cases of β thalassemia and 9 cases of αβ thalassemia. Among the patients with elevated HbA2, 68.67% were detected β thalassemia, 3.00% αβ thalassemia, 9.33% were suspected to be caused by macrocytosis, 6.33% by thyroid dysfunction, and 12.67% by uncertainty of the method. Among the patients with reduced HbA2, 21.48% were detected α thalassemia, 60.00% iron deficiency anemia, 8.15% were suspected to be caused by thyroid dysfunction, and 10.37% by uncertainty of the method. Among the patients with elevated F alone, the results of thalassemia gene detection were negative, 40.91% of them were suspected to be caused by macrocytosis, 27.27% by hereditary persistence of fetal hemoglobin, 29.55% by special physiological condition of pregnant women, and 2.27% by hyperthyroidism. Abnormal hemoglobin bands were detected in 7 patients, including 4 cases of hemoglobin D, 2 cases of hemoglobin E, and 1 case of hemoglobin J.@*CONCLUSION@#Thalassemia, iron deficiency anemia, macrocytosis such as megaloblastic anemia and non-severe aplastic anemia, thyroid dysfunction, hereditary persistence of fetal hemoglobin, abnormal hemoglobin diseases, the uncertainty of the method are all important causes of abnormal hemoglobin electrophoresis results. In clinical work, the patient's indicators should be comprehensively analyzed to determine the possible cause.

HemoTypeSC point-of-care testing shows high sensitivity with alkaline cellulose acetate hemoglobin electrophoresis for screening hemoglobin SS and SC genotypes

ABSTRACT Introduction: By providing timely actionable results for prompt management, point-of-care testing (POCT) kits have revolutionised medical care for various diseases, ranging from infectious diseases like malaria to genetic disorders, such as sickle cell disease (SCD). They are, however, underutilised in the diagnosis of SCD in developing countries, where the need is greatest. Objective: The study was aimed at assessing the sensitivity of HemoTypeSC POCT among a cohort of children with SCD, previously diagnosed by Alkaline cellulose acetate hemoglobin electrophoresis (ACAE), with or without high-performance liquid chromatography (HPLC). Methods: In this descriptive cross-sectional study, HemoTypeSC test was conducted on all participants and its sensitivity was determined by comparing results with those obtained using ACAE. Discordance was verified with HPLC. Results: One hundred and forty-five children aged one to 19 years were studied. There were 84 males and 61 females (male: female ratio = 1.4:1). The HemoTypeSC was able to correctly diagnose sickle cell anemia (SCA) and hemoglobin SC in all (100%) of the children tested. Conclusion: The HemoTypeSC shows high sensitivity in detecting SCA and hemoglobin SC. Hence, it is useful for targeted screening of individuals suspected of having SCD, leading to rapid diagnosis of these hemoglobinopathies, even in resource-constrained settings.

Prevalence of hemoglobin abnormalities in an apparently healthy population in Benin

ABSTRACT Background: Sickle cell disease is the most common monogenic disorder in humans and is a major public health concern in sub-Saharan Africa. In Benin, the prevalence of sickle cell disease is estimated to be 4.8%. Our study aimed to describe the prevalence of hemoglobin abnormalities in an apparently healthy Benin population. Methods: One thousand four hundred and eighty-three men and women, apparently in good health after medical screening, were tested for hemoglobin abnormalities by hemoglobin electrophoresis and the Emmel test. Subjects who were found to have homozygous or double heterozygous hemoglobin abnormalities, were re-sampled and a confirmation hemogram and hemoglobin electrophoresis test by capillary electrophoresis was performed. Results: Our study population was predominantly male (97.7%) with an average age of 21.3 years. 1390 subjects reported that they did not know their hemoglobin electrophoresis status. Hemoglobin electrophoresis profiles found were as follows: 1077 (72.6%) AA (normal), 238 (16.1%) AS, 161 (10.9%) AC, 3 (0.2%) SC, 4 (0.2%) CC and 0 (0%) SS. The 406 subjects with abnormal hemoglobin had balanced somatic growth, with general physical examination results showing no abnormalities. In the seven subjects with major sickle cell syndrome or hemoglobinosis (SC and CC), their values of various hemogram parameters were normal apart from the discreet presence of microcytic anemia. Conclusion: Our study highlights the need for increased routine testing of hemoglobin abnormalities and newborn screening for sickle cell disease in order to enhance early disease detection, prevention and comprehensive care.

Pattern of hemoglobinopathies and thalassemia in Manipur, India

Background: Hemoglobinopathies are the commonest genetic disorders worldwide. Thalassemia Major, Thalassemia Intermedia and Sickle Cell Disease are the major disorders that require lifelong management and are to be considered for prevention. In India, Beta-Thalassemia is prevalent across the country, with an average frequency of carriers being 3-4%.Methods: This is a cross sectional study conducted between June 2016 - May 2017 in the Department of Medicine, RIMS Imphal in 453 patients as a workup for anemia and clinically suspected cases of Hemoglobinopathy or beta thalassemia. Blood samples were collected and sent for Haemoglobin Electrophoresis using cellulose alkaline technique.Results: Among the 453 cases of the population surveyed, 35% showed the presence of abnormal hemoglobin. 16% were found to be beta thalassemia carrier, 11.69% HbE trait, 6.62% Homozygous HbE, 0.4% beta thalassemia and 0.7% had Hereditary persistence of HbF.Conclusions: High prevalence of Beta Thalassemia trait occurred more frequently than other Hemoglobinopathies. The study concludes that it is immensely important epidemiologically to explore the haemoglobin variants in Manipur so that the carriers can be detected for prevention of more serious disorder in the future generations.

Comparative study of solubility and hemoglobin electrophoresis with high performance liquid chromatography (HPLC) for screening of hemoglobinopathies and thalassemia: Study from central India

Introduction: High prevalence of hemoglobinopathies is seen in central India, screening and genetic counseling are essential for early detection and management. Aim: The retrospective study was performed at Regional hemoglobinopathy detection and management centre (RHDMC) Nagpur, central India to find out relative frequencies of hemoglobinopathies and thalassemia present using solubility test, hemoglobin electrophoresis and high performance liquid chromatography (HPLC) as screening method and to compare results of HPLC with solubility and electrophoresis. Materials and methods: A total of 105,211 cases were screened for sickle cell disease (SCD) and sickle cell trait (SCT) by solubility test during the period of January 2003 to January 2014. Of these 105,211 samples, 60,000 samples which were solubility positive, with doubtful solubility and solubility negative but suspicious for hemoglobinopathy and thalassemia also the cases of anemia were studied by hemoglobin electrophoresis at alkaline pH 8.6. Of which 5,111 cases were further Shrikhande Anuradha V., Pawar Prajkta S. Comparative study of solubility and hemoglobin electrophoresis with high performance liquid chromatography (HPLC) for screening of hemoglobinopathies and thalassemia: Study from central India. IAIM, 2019; 6(3): 111-126. Page 112 studied by HPLC and results of HPLC were compared with combined solubility and Hb electrophoresis. Results: Of 105,211 cases screened for hemoglobinopathy by solubility and electrophoresis, 12,979 (12.33%) were having sickle cell trait (SCT) and 3,062 (2.91%) were of sickle cell disease (SCD). Of 5,111 (100%) HPLC study cases, total SCD and SCT were 3,132 (61.27%) followed by 315 (6.16%) of beta-thalassemia trait and 264 (5.16%) cases of compound heterozygous for HbS and betathalassemia. Hemoglobinopathies E and D alone and its combination with HbS or beta-thalassemia were also found. Rare cases of HbD Iran, HbJ variant and HbQ India, Hb Abruzzo and delta-beta thalassemia were detected. Combined solubility and hemoglobin electrophoresis was effective for diagnosis of SCD and SCT when compared to HPLC with good agreement between two test by kappa statistics, however for detection of beta-thalassemia trait and for compound heterozygous for HbS and beta-thalassemia false negatives cases were more, chi square test showed highly significant P value <0.01. Conclusion: Combined solubility and electrophoresis are simple and cost effective alternative to HPLC for screening large population with high prevalence of SCD when resources are limited but for beta-thalassemia screening HPLC is mandatory.

Screening of thalassemia and other hemoglobinopathies in blood donors by capillary hemoglobin electrophoresis system

Introduction: Hemoglobinopathies are a group of genetic disorders of hemoglobin. Because of consanguinity, caste and area endogamy, some communities show a very high incidence, making the disease a major public health problem. The aim of this study is to screen for thalassemia and abnormal hemoglobinopathies in blood donors by capillary electrophoresis system for early detection, management and referring positive cases for genetic counselling. Materials and methods: This was a hospital based observational study which was done for a period of one year and EDTA blood samples of anaemic blood donors showing microcytic hypochromic blood picture or low hemoglobin (<7 gm/dl) and low MCV, MCH values were studied. Both voluntary and replacement donors were included in the study. Screening for β thalassemia and other hemoglobinopathies was done in Department of Transfusion Medicine using MINICAP FLEXPIERCING Capillary haemoglobin electrophoresis system. At the end of the analysis, relative quantification of individual hemoglobin fractions was performed automatically and profiles can be analyzed; the hemoglobin fractions, Hb A, Hb F, Hb A2 were automatically identified. Results: We had screened 36 blood donors having microcytic hypochromic picture. Out of which 20 turned out to be Beta Thalassemia Trait by capillary hemoglobin electrophoresis system. Therefore, out of the sample size of 36 blood donors, 55.5% were Beta Thalassemia trait. Conclusion: This study was based to screen thalassemic patients as carriers along with hemoglobinopathies so as to reduce the rate of affected infants and screen even asymptomatic patients for early management and genetic counselling

Analysis of results of genotyping and screening for infertile subjects with alpha-thalassemia in Guangxi / 实用医学杂志

Objective Investigation of the carrier rate, genotyping and genotype frequency of alpha-thalassemia among infertile subjects in Guangxi, and analysis of the relationship between the results of hemoglobin electrophoresis and hematologic parameters among patients with three phenotypes of alpha-thalassemia and subjects with non-thalassemia. Methods The preliminarily patients who were diagnosed as beta-thalassemia via HbA2>3.5％ and/or HbF> 2％ were excluded. Alpha-thalassemia genes of 10 020 infertile subjects were detected in our center from 2017 to 2018, and the results of hemoglobin electrophoresis and hematologic parameters in patients with three phenotypes of alpha-thalassemia were compared. Results 624 patients with alpha-thalassemia were confirmed via gene diagnostic technique, including 19 genotypes, total carrier rate for 6.23％, 275 (2.74％) patients with silent alpha-thalassemia, 326 (3.25％) patients with alpha-thalassemia trait and 23 (0.23％) patients with HbH disease. The most common genotype was--SEA/αα, followed by-α3.7/αα and α, CSα/αα. The parameters of MCV, MCH, MCHC, Hb, HCT, HbA2 were lower, but the value of RBC were higher (both P < 0.05) , in patients with three phenotypes of alpha-thalassemia than subjects with non-thalassemia. The parameters mentioned above excluding HbA2 in patients with alpha-thalassemia showed the following regularity : silent alpha-thalassemia> potential alpha-thalassemia> HbH disease. RBC value tended to increase gradually in patients with silent alpha-thalassemia, potential alpha-thalassemia and HbH disease. Conclusion Infertility with alpha-thalassemia is very popular in Guangxi, especially--SEA/αα which is the most common genotype. The value of MCV, MCH, MCHC, Hb, RBC and HCT are conducive to screening for infertile subjects with alpha-thalassemia, and have certain clinical value for differentiating three phenotypes of alpha-thalassemia.

Talasemias: Aspectos clínicos / Thalassemias: Clinical aspects / Talassemias: Aspectos clínicos

Los síndromes talasémicos, junto con las hemoglobinopatías talasémicas, las hemoglobinopatías estructurales y los síndromes de sobreexpresión representan las diferentes formas clínicas de las hemoglobinopatías. Los defectos genéticos responsables de los síndromes talasémicos determinan la síntesis disminuída o nula de la cadena de globina correspondiente. Según la cadena cuya síntesis es defectuosa, los síndromes talasémicos se clasifican en a-talasemias, b-talasemias, etc. Según las diferentes combinaciones de fenotipos particulares, las a-talasemias se clasifican en silente, portador, enfermedad con hemoglobina H e hidropesía fetal, y las b-talasemias en menor, intermedia y mayor. La sospecha diagnóstica de los síndromes talasémicos leves y de las hemoglobinopatías talasémicas es fácil a partir de la anemia leve con marcada microcitosis hipocrómica, ausencia indudable de ferropenia y cuadro familiar positivo. La electroforesis de hemoglobina con una cuantificación de hemoglobina A2 mayor de 3,5% prácticamente confirma el diagnóstico de una b-talasemia menor, mientras que una hemoglobina A2 normal o disminuida va a hacer sospechar una a-talasemia leve cuyo diagnóstico debe ser confirmado por estudio de ADN. Una vez establecida la condición talasémica del propósito es imprescindible identificar qué familiares consanguíneos son o no portadores del mismo gen talasémico, y estudiar a los cónyuges de los talasémicos detectados, a fin de prever, a través del consejo genético, el nacimiento de hijos homocigotas o doble heterocigotas con formas más severas de talasemias o hemoglobinopatías.

Thalassemic syndromes, together with thalassemic hemoglobinopathies, structural hemoglobinopathies and over-expression syndromes represent the different clinical presentations of hemoglobinopathies, which are the mutational or deletional defects of globin genes. Genetic defects responsible for thalassemic syndromes determine a reduced or a lack of synthesis of the related chain. According to the defective synthesized chain, thalassemias are classified into a-thalassemias, b-thalassemias, etc. Depending on the different combinations of two or more phenotypes, a-thalassemias are classified into silent, carrier, Hb H disease and fetal hydrops, while b-thalassemias are classified into minor, intermediate and major b-thalassemia. Diagnostic suspicion of mild thalassemic syndromes and thalassemic hemoglobinopathies is easy based on a mild anemia with pronounced microcytosis and hypochromia, unquestionable absence of iron deficiency and positive family background. Hemoglobin electrophoresis with A2 hemoglobin level higher than 3.5% almost confirms a b-thalassemia minor, while a low or normal A2 hemoglobin level makes mild a-thalassemia suspicious and diagnosis must be confirmed by DNA study. Once the thalassemic condition of the propositus is confirmed, it is essential to identify which consanguineous relatives are or are not carriers of the same thalassemic gene, and then to study the couples of all already identified thalassemic relatives, in order to forecast, through genetic counselling, the birth of homozygous or double heterozygous children with more severe thalassemic or hemoglobinopathic conditions.

As síndromes talassêmicas, junto com as hemoglobinopatias talassêmicas, as hemoglobinopatias estruturais e as síndromes de sobre-expressão representam as diferentes formas clínicas das hemoglobinopatias. Os defeitos genéticos responsáveis pelas síndromes talassêmicas determinam a síntese diminuída ou nula da cadeia de globina correspondente. Segundo a cadeia cuja síntese é defeituosa, as síndromes talassêmicas são classificadas em a-talassemias, b-talassemias, etc. Conforme as diferentes combinações de fenótipos particulares, as a-talassemias são classificadas em silente, portador, doença com hemoglobina H e hidropesia fetal, e as b-talassemias em menor, intermediária e maior. A suspeita diagnóstica das síndromes talassêmicas leves e das hemoglobinopatias talassêmicas é fácil a partir da anemia leve com marcada microcitose hipocrômica, ausência induvidável de ferropenia e quadro familiar positivo. A eletroforese de hemoglobina com uma quantificação de hemoglobina A2 maior de 3,5% praticamente confirma o diagnóstico de uma b-talassemia menor, ao passo que uma hemoglobina A2 normal ou diminuída vai fazer suspeitar uma a-talassemia leve cujo diagnóstico deve ser confirmado por estudo de DNA. Assim que é estabelecida a condição talassêmica do propósito, é imprescindível identificar quais são os familiares consanguíneos e quais não são portadores do mesmo gene talassêmico, e estudar os cônjuges dos talassêmicos detectados, visando a prever, através do conselho genético, o nascimento de filhos homozigotas ou duplo-heterozigotas com formas mais severas de talassemias ou hemoglobinopatias.

Anemia microcítica-hipocrómica: anemia ferropénica versus b talasemia menor / Microcytic and hypochromic anemia: iron deficiency anemia versus b thalassemia trait / Anemia microcitica-hipocrômica: anemia ferropênica versus b talassemia menor

Las anemias microcíticas hipocrómicas (m-H) presentan VCM<80 fL y HCM<27 pg. Son producto de la baja biodisponibilidad del hierro (Fe), o del defecto de la síntesis de globinas o del HEMO. La más frecuente es la anemia por deficiencia de hierro (ADH), seguida por las talasemias y las anemias de procesos crónicos. Menos frecuentes son aquellas por defectos en el HEMO o por causas genéticas del metabolismo del Fe. El objetivo del trabajo es revisar, por medio de parámetros de distinta complejidad, diferencias entre ADH y b talasemia heterocigota (b-Tal-het), las m-H de mayor prevalencia en nuestro medio. Los recuentos de eritrocitos y reticulocitos, hemoglobina, ferremia, ferritina, saturación de la transferrina, HbA2, porcentaje de alteraciones morfológicas son menores en la ADH. El VCM, el HCM, la ADE, los índices de microcitosis, transferrina, y los receptores solubles de transferrina son menores en b-Tal-het. El estrés oxidativo está aumentado en ambas patologías. En el análisis de estos parámetros se discute el grado de deficiencia de Fe y/o la mutación de b-Tal-het. Se aplica un algoritmo para m-H a partir del Fe sérico. Una vez descartadas las m-H más comunes, se debe investigar a-Tal-het, la cual se considera la causa de la mayoría de m-H inexplicadas.

Microcytic hypochromic anemia (m-H) presents MCV<80 fL and MCH<27 pg. m-H can result from iron availability, defects in globin or HEMO synthesis. The most frequent m-H is iron deficiency anemia (IDA), followed by thalassemias and anemia chronic disease. Rare m-H are a consequence of HEME defects or iron metabolism genetic defects. The aim of this study is to review the differential diagnosis between IDA and b thalassemia trait (b thal trait), the most frequent in our environment. Results of laboratory tests are analysed. Erythrocytes, hemoglobin, reticulocytes, iron, ferritin, transferrin saturation, HbA2 and percentage of morphologic changes are lower in IDA compared with b Thal trait. MCV, MCH, RDW, microcytic index, transferrin and soluble transferrin receptor are higher in IDA compared with b Thal trait. Oxidative stress is increased in the two forms of microcytoses. Degree iron deficiency in IDA and b Thal trait mutation must be considered in the analysis of the parameters. A flowchart is proposed to evaluate m-H stemming from serum iron value. After excluding the most frequent causes of microcytic anemia, a thalassemia trait must be considered.

As anemias microcíticas hipocrômicas (m-H) apresentam VCM<80 fL e HCM<27 pg. São produto da baixa biodisponibilidade do ferro (Fe), ou do defeito da síntese de globinas ou do HEMO. A mais frequente é a anemia por deficiência de ferro (ADH), seguida pelas talassemias e as anemias de processos crônicos. Menos frequentes são aquelas por defeitos no HEMO ou por causas genéticas do metabolismo do Fe. O objetivo do trabalho é revisar, através de parâmetros de diversa complexidade, diferenças entre ADH e b talassemia heterocigota (b-Tal-het), as m-H de maior prevalência no nosso meio. As contagens de eritrócitos e reticulócitos, hemoglobina, ferremia, ferritina, saturação da transferrina, HbA2, percentagem de alterações morfológicas são menores em ADH. O VCM, o HCM, a ADE, os índices de microcitose, transferrina, receptores solúveis de transferrina são menores em b-Tal-het. O estresse oxidativo está aumentado em ambas as patologias. Na análise destes parâmetros é discutido o grau de deficiência de Fe e/ou a mutação de b-Tal-het. Aplica-se um algoritmo para m-H a partir do Fe sérico. Depois de serem descartadas as m-H mais comuns, deve investigar-se a-Tal-het, a qual é considerada a causa da maior parte de m-H inexplicadas.

The value of combined tests of hemoglobin electrophoresis and genetic testing in neonatal cord blood screening for β-thalassemia / 国际检验医学杂志

Objective To explore the clinic utility of Hb A level in neonatal cord blood screening for β‐thalassemia .Methods A total of 1 599 neonatal cord specimens whose parents were carriers of β‐thalassemia prenatal diagnosised by routine molecular genet‐ic were collected by cordocentesis .These samples were analyzed by the capillary electrophoresis system (Sebia) .Results Among 1 599 fetuses ,186 were diagnosed as β‐thalassemia carriers ,68 were β‐thalasseima intermedia/major .ROC analysis demonstrated that the optimal cutoff value for identifying β‐thalassemia carrier from the Hb A level was 5 .15% (sensitivity = 83 .9% , specificity = 82 .3% ) ,and that was 3 .2% for β‐thalasseima intermedia/major (sensitivity = 100 .0% ,specificity = 99 .4% ) .Conclu‐sion The Hb A level of cord blood was an effective marker to screen the β‐thalassemia for fetuses and is therefore well‐suited for clinical diagnostic use .

Prevalence of hemoglobinopathies in school children: the importance of using confirmatory methods / Prevalência das hemoglobinopatias em crianças em idade escolar: a importância do uso de métodos de confirmação

The hemoglobinopathies are included among the most common genetic diseases in the world. In Brazil, hemoglobinopathies are related to the diversity of racial backgrounds and the degree of interbreeding. The study focused on the prevalence of hemoglobinopathies using conventional and confirmatory laboratory tests in children from public schools in Ribeirão Preto-SP. The study involved the participation of 427 children between six and nine years of age. Hematologic evaluation, hemoglobin electrophoresis on cellulose acetate at alkaline pH, quantification of hemoglobin fractions by high performance liquid chromatography (HPLC) and detection of -α^3.7 deletion for α thalassemia by polymerase chain reaction were performed. The results of hemoglobin electrophoresis on cellulose acetate and HPLC of the children studied showed the presence of 30 children (7%) with hemoglobinopathies. Eleven children presented results indicating suspicion of S/β-thalassemia; their parents and/or siblings were evaluated and confirmed the presence of only Hb S. The analysis of deletion -α^3.7to characterize α-thalassemias sampling performed on 207 participants identified 26 children (12.6%) with deletion -α^3.7. Thus, 54 (12.6%) of the children studied present this genetic alteration. For the detection of α-thalassemias it is necessary to use confirmatory methods such as molecular analysis and evaluation of family members in doubtful cases to facilitate genetic counseling in families, in which deletion -α^3.7 is more frequent in Brazil...

As hemoglobinopatias estão incluídas nas doenças genéticas mais comuns no mundo. No Brasil, as hemoglobinopatias são relatadas pela diversidade racial e o grau de miscigenação. O estudo focou a prevalência das hemoglobinopatias usando métodos laboratoriais convencionais como a eletroforese de hemoglobina em acetato de celulose em pH alcalino e confirmatório por reação em cadeia de polimerase (PCR) em crianças de escolas públicas de Ribeirão Preto-SP. O estudo envolveu a participação de 427 crianças entre 6-9 anos de idade. Determinaram-se os valores hematológicos, efetuou-se eletroforese de hemoglobina em acetato de celulose em pH alcalino, quantificação das frações de hemoglobina por HPLC e a detecção da deleção -α^3,7 pela PCR. Os resultados da eletroforese de hemoglobina em acetato de celulose e do HPLC, nas crianças estudadas, mostraram a presença de 30 crianças (7%) com hemoglobinopatias. Onze crianças apresentaram resultado indicando a suspeita de S/β-talassemia; seus pais e/ou irmãos confirmaram a presença de apenas a Hb S. A análise da deleção -α^3,7, uma das alterações que estão presentes na α-talassemia, realizada em 207 participantes, identificou 26 crianças (12,6%) com a deleção -α^3,7. Dessa forma, 54 (12,6%) das crianças estudadas apresentam hemoglobinopatias. Para a deleção da α-talassemias é necessário utilizar métodos confirmatórios como as análises moleculares e avaliação de membros da família, em casos duvidosos, facilitando o aconselhamento genético nas famílias, sendo a deleção -α^3,7 mais frequente no Brasil...

12 898 cases of full-automatic hemoglobin electrophoresis and result analysis / 国际检验医学杂志

Objective To retrospectively analyze the result of hemoglobin(Hb)test by using full-automatic Hb electrophoresis and evaluate the its significance in hemoglobinopathy.Methods The data of patients who underwent Hb electrophoresis test and regular blood tests in the hospital from January 2011 to December 2013 were included in the study.The test results were recorded including mean corpuscular volume(MCV),mean corpuscular hemoglobin(MCH)and results of Hb electrophoresis test.Final diag-nosis were made for suspected patients by using genetic testing,then disease detection rates and gene coincidence rates and constitu-ent ratios were calculated.Results 12 898 cases were included in the study,after statistical analysis the MCV was(85.32±13.61) fL,MCH was(29.87±6.44)pg.By using automatic hemoglobin electrophoresis,1 315 cases were found to be positive,in which 568 were male,747 were female,the detection rate was 10.19%.In the 1 315 patients,there were 761 cases suspectedα-thalassemia,ac-counted for 5.90%.There were 495 cases of suspectedβ-thalassemia,accounted for 3.84%,11 patients with HbJ(0.08%),15 pa-tients with HbK(0.12%),9 patients with HbG(0.07%),3 patients with HbD(0.02%),21 patients with HbE(0.16%).The sus-pected case′s final diagnosis were made by using genetic testing,α-thalassemia gene′s coincidence rate was 80.55%,β-thalassemia gene′s coincidence rate was 96.77%.Conclusion Automatic hemoglobin electrophoresis detection is of great significance for the di-agnosis of hemoglobinopathy.

Comparative analysis of cellulose acetate hemoglobin electrophoresis and high performance liquid chromatography for quantitative determination of hemoglobin A2

BACKGROUND: The present study is designed to evaluate the reliability and cost effectiveness of cellulose acetate Hb electrophoresis and high performance liquid chromatography (HPLC) in the determination of HbA2 levels. METHODS: The test population comprised 160 individuals divided into four groups: normal individuals, beta-thalassemia trait (BTT) patients, iron deficiency anemia (IDA) patients, and co-morbid patients (BTT with IDA). HbA2 levels determined using cellulose acetate Hb electrophoresis and HPLC were compared. RESULTS: HbA2 levels were found to be diagnostic for classical BTT using either method. In co-morbid cases, both techniques failed to diagnose all cases of BTT. The sensitivity, specificity, and Youden's index for detection of the co-morbid condition was 69% and 66% for HPLC and cellulose acetate Hb electrophoresis, respectively. CONCLUSION: This study revealed that semi-automated cellulose acetate Hb electrophoresis is more suitable for use in beta-thalassemia prevention programs in low-income countries like Pakistan. This technique is easily available, simple and cost effective.

The thalassemia screening analysis of 2 650 cases of childbearing women / 重庆医学

Objective To investigate the incidence of poverty ,population carrying rate and its genetic type through the thalasse‐mia screening analysis of 2 650 cases of childbearing women .Methods Hematologic examination and hemoglobin electrophoresis were applied in people who were laboratory tested the crowd ,screening suspected people ,then use the genetic analysis confirm the diagnoses .Results Preliminary screening of the 536 cases which were suspected the thalassemia (or gene carriers) ,hematologic ex‐amination showed that the red blood cells ,reticulocyte counts in the cases were significantly higher than those in the controls ;and hemoglobin ,mean corpuscular volume (MCV)and mean corpuscular hemoglobin (MCH) were significantly lower .Hemoglobin elec‐trophoresis test showed that in 512 abnormal cases ,68 cases were diagnosed as α thalassemia and 438 cases were β thalassemia(506 cases in total ,accounting for 19 .09% of the total number) .In this area ,Southeast Asia(SEA) heterozygotes(‐SEA /αα) ,right hetero‐zygotes(‐α3 .7 /αα) ,left heterozygotes(‐α4 .2 /αα) ,Hb Constant Spring(‐αCS /αα) were common type of α thalassemia ;CD41‐42 hetero‐zygotes ,CD17 heterozygotes ,CD71‐72 heterozygotes and CD28 heterozygotes were common type of β thalassemia .Conclusion In Guangxi ,there was high incidence rate of thalassemia ,thus ,though premarital and prenancy anterior screening ,guide the rational marriage and pregnancy ,and through the crowd to intervene to prevent common human monogenic death and disabling genetic dis‐orders are of great importance for prepotency promotion and population quality improve .

Diagnostic utility of hemoglobin electrophoresis in neonatal cord blood screening for thalassemia / 实用医学杂志

Objective To study the diagnostic utility of hemoglobin electrophoresis in neonatal cord blood screening for thalassemia. Methods Between January 2012 and December 2013, 14032 core blood samples which were from different 21 Women and Children Hospitals in Guangdong were performed for the neonatal screening with hemoglobin electrophoresis. The positive samples of hemoglobin electrophoresis were recalled for genetic testing. Results Out of 1445 (11.07%) positive samples of hemoglobin electrophoresis , 1075 (54.08%) cases were suspected for α-thalassemia, 478 (3.41%) cases were suspected for β-thalassemia, 127 (0.91%) cases were suspected for abnormal hemoglobin. With the genetic testing, 967 cases were diagnosed as α-thalassemia, 404 cases were diagnosed asβ-thalassemia. The coincidence rate ofα-thalassemia andβ-thalassemia were 89.95%and 82.96%, respectively. Besides, 124 cases were diagnosed as abnormal hemoglobin, including 38 cases of Hb E, 28 cases of Hb Q, 21 cases of Hb D, 19 cases of Hb New York, 13 cases of Hb J, and 5 cases of Hb J. Conclusion Hemoglobin electrophoresis was definitely helpful in the neonatal cord blood screening for thalassemia and abnormal hemoglobin.

Application of automated high-performance liquid chromatography in the diagnosis of thalassemia / 临床儿科杂志

Objective To evaluate the application of high-performance liquid chromatography (HPLC) in diagnosis and screening of thalassemia. Methods Automated HPLC was used to measure HbF and HbA2 in 100 genetically diagnosed thalas-semic patients and 35 normal children. The results were compared with those from traditional tests including alkali denaturation test and cellulose acetate electrophoresis. The diagnose accordance rates, sensitivity and specificity were compared. Results Seventy-fourβthalassemia, 64 were heterozygous with single mutations and 10 were compound heterozygous with double muta-tions. Twenty-sixαthalassemia, 25 were compound mutations and one was heterozygous with single mutation. The HbF percent-age from HPLC was higher than that from alkali denaturation tests in either thalassemia or normal children (P<0.01). HbF level from HPLC inα-thalassemia was signiifcantly different from that in the normal children (P=0.011). The percentage of HbA2 from HPLC was higher than that from cellulose acetate electrophoresis (P=0.010). HbA2 in the single heterozygousβ-thalassemia were twice higher than that in the double heterozygous mutatedβ-thalassemia (P<0.01). The combination of HbF-HbA2 (≥4.0%) from HPLC with MCV (<80 lf) and MCH (<27 pg) had high accordance rates (99.3%), sensitivity (99.0%) and speciifcity (100.0%) in diagnosis of thalassemia. Conclusions When the results of HPLC are combined with MCV and MCH, it can be applied to the diagnosis of thalassemia with high speciifcity, high sensitivity and has high diagnostic accordance rate with genetic results. HPLC can be an ideal approach to screenβthalassemia.

Clinical feature and molecular diagnosis of abnormal Hb Shaare Zedek in a Chinese family / 中华检验医学杂志

Objective To diagnose a rare variant Hb Shaare Zedek in a Chinese family,and describe its clinical feature.Methods Blood samples of seven members of three generation were collected.Standard blood routine analysis,hemoglobin electrophoresis and blood gas analysis were used for phenotype analysis.Gap-PCR and reverse dot blot analysis were used to detect common thalassemia mutations.DNA sequence analysis of the human α and β globin genes were used to identify the mutation site of these samples.Results The result of blood routine analysis was normal in the proband,but a abnormal hemoglobin band (22.4％,capillary assay) was found by hemoglobin electrophoresis.In the blood gas analysis,the partial pressure of oxygen and blood oxygen saturation were 72.0 mm Hg ( 1 mm Hg =0.133 kPa) and 93.0％ in the proband.The heterozygous mutations in αl globin gene at codon 56 ( AAG ＞ GAG)which leaded Glu substitution to Lys were identified in the proband.Other family members who carried the same mutation showed similar phenotype,with abnormal hemoglobin band ( 22.4％ - 23.9％,capillary assay),low partial pressure of oxygen (59.0 - 72.0 mm Hg) and blood oxygen saturation (91.0％ -93.0％).Conclusions The heterozygote of Hb Shaare Zedek leads to slight symptoms with abnormal hemoglobin band,decreased partial pressure of oxygen and blood oxygen saturation.Discovery of this mutation enriches the abnormal hemoglobin spetrum of Chinese people,and it is useful for the clinical diagnosis and genetic counseling of hemoglobinopathies.

Estudo comparativo entre metodologias de triagem para detecção de hemoglobina S em bancos de sangue / Comparative study between methods of screening for detection of hemoglobin S in the blood banks

INTRODUÇÃO: O traço falciforme é a presença em heterozigose da hemoglobina S (HbS). A partir de junho de 2004, por meio da RDC 153/04, tornou-se obrigatória a triagem de hemoglobinas anormais em doadores de sangue. OBJETIVO: O objetivo deste estudo foi a comparação de diferentes metodologias de triagem utilizadas nos bancos de sangue para a detecção da HbS. Material e método: No período de abril de 2007 a abril de 2008, foram realizados três métodos de detecção de HbS em 4.108 doadores de sangue aptos que se apresentaram ao banco de sangue do Hospital Universitário de Santa Maria (HUSM). O estudo comparativo entre as metodologias incluiu os testes de solubilidade e de gel-centrifugação, tendo como referência de positividade a presença de HbS na eletroforese de hemoglobina. RESULTADOS: Dos 4.108 doadores estudados, 23 (0,56 por cento) apresentaram resultado positivo para HbS e dois (0,05 por cento) para HbC. Das amostras positivas para HbS detectadas por eletroforese qualitativa, 22 (95,6 por cento) foram detectadas pelo teste de solubilidade e 20 (86,9 por cento) pelo de gel-centrifugação. CONCLUSÃO: A eletroforese de hemoglobinas representou a melhor metodologia na identificação de hemoglobinas variantes e, portanto, deve ser valorizada quando se trata de diagnóstico para triagens em bancos de sangue pelo seu grau de sensibilidade, minimizando ao máximo os resultados falsos negativos e garantindo a qualidade do sangue que estará sendo utilizado.

INTRODUCTION: The sickle cell trait is the presence of hemoglobin S (HbS) in heterozygosity. According to RDC regulation 153/04, abnormal hemoglobin screening has become mandatory in blood donation samples since June 2004. OBJECTIVE: The aim of this study was to compare different screening methods used in blood banks for HbS detection. Material and method: From April 2007 to April 2008, three HbS detection methods were applied in 4,108 suitable blood samples from the blood bank of the University Hospital of Santa Maria (HUSM). The comparative study among the methods comprised solubility tests and gel-centrifuge (ID-HbS). Furthermore, the positivity reference was the presence of HbS on hemoglobin electrophoresis. RESULTS: Twenty-three (0.56 percent) out of 4,108 samples showed positivity for HbS and two (0.05 percent) showed positivity for HbC. Twenty-two (95.6 percent) out of 23 HbS positive samples determined through qualitative electrophoresis were detected by solubility test and 20 (86.9 percent) were detected by gel-centrifugation test. CONCLUSION: Hemoglobin electrophoresis proved the best method in the identification of hemoglobin variants and, therefore, worthwhile when it comes to diagnostic screening in blood banks due to its high sensitivity, which keeps false-negative results to a minimum and ensures blood quality.

A hospital based study of Hereditary Hemolytic Anaemias in Davanagere district of Karnataka, India.

Background: Hereditary hemolytic anaemias constitute important cause of mortality and morbidity in developing countries next only to infection and malnutrition.These group of anaemias have various clinical presentations starting from their age of onset of symptoms, failure to thrive, anaemia, prostration, jaundice, splenomegaly, cholelithiasis, cardiomegaly, congestive cardiac failure, severe life threatening infections and chronic disabilities leading to distress in the families. Methodology: An analysis of 40 cases of hereditary hemolytic anaemia in the age group of 2 months to 12 years was done in the present study. On the basis of clinical presentations, physical findings, routine hematological investigations and hemoglobin electrophoresis pattern in hemoglobin defects were carried out to identify the type of hemolytic anaemias. Results: This clinocohematological study of hereditary hemolytic anaemia showed membrane defects- Hereditary spherocytosis in 4 cases (10%). The remaining 36 cases were having diseases affecting hemoglobin molecule which included Sickle cell anaemia-5 cases (12.5%), Sickle cell trait- 1 case (2.5%), Sickle cell/􀈕 thalassemia-1 case (2.5%), 􀈕 thalassemia major- 23 cases (57.5%) and 􀈕 thalassemia trait 6 cases(15%). Hereditary hemolytic anaemia with enzyme defects were not observed in this study. Majority of these cases presented with progressive pallor and hepatosplenomegaly. Peripheral blood smear examination showed microcytic hypochromic anaemia (87.5%) in majority of the cases. All cases were associated with reticulocytosis. Hemoglobin electrophoresis confirmed the diagnosis. Conclusion: Inspite of advanced diagnostic inestigations, the basic hematological investigation remains first panel or step towards the approach to diagnose hereditary hemolytic anaemia and hemoglobin electrophoresis will help in confirming the diagnosis.