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1.
Ann Hematol ; 99(7): 1475-1483, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32524201

RESUMO

Large deletions in the ß-globin gene cluster lead to increased HbF levels by delaying the γ- to ß-globin switch process. However, these deletions when inherited as a homozygous condition or when co-inherited with ß-thalassemia result in variable clinical phenotypes. Individuals or families with a clinically presenting child, where the parents had HbF levels ≥ 10%, were further screened for the presence of large ß-globin cluster deletions. Six deletions in the ß-globin gene cluster were screened by GAP-PCR, and the uncharacterized deletions were further analyzed by gene dosage or by multiplex ligation-dependent probe amplification (MLPA). Among 192 individuals suspected for the inheritance of large deletions, 138 were heterozygous for large deletions, 45 were compound heterozygous of a large ß-globin cluster deletion and ß-thalassemia, and 9 were found to be homozygous for deletions. Among the heterozygotes, the Asian Indian inversion-deletion was found to be the most common deletion (39.9%), followed by the HPFH-3 deletion (30.0%). Other deletions 49.3 kb, δß-thalassemia (21.2%), and 32.6 kb deletion (4.4%) were also found to be prevalent in our population. Patients compound heterozygous or homozygous for HPFH-3 and 32.6 kb deletions showed a milder clinical presentation, as compared with the patients compound heterozygous or homozygous for the Asian Indian inversion-deletion and 49.3 kb δß-thalassemia. This comprehensive study highlights the mutation spectrum of large ß-globin cluster deletions and the clinical heterogeneity in the patients homozygous or compound heterozygous with ß-thalassemia, thus asserting the need for molecular characterization of these deletions.


Assuntos
Hemoglobina Fetal/genética , Estudos de Associação Genética , Heterogeneidade Genética , Talassemia beta/epidemiologia , Talassemia beta/genética , Talassemia delta/epidemiologia , Talassemia delta/genética , Idade de Início , Criança , Mortalidade da Criança , Pré-Escolar , Feminino , Hemoglobina Fetal/análise , Estudos de Associação Genética/estatística & dados numéricos , Humanos , Índia/epidemiologia , Lactente , Padrões de Herança/genética , Masculino , Talassemia beta/sangue , Talassemia beta/mortalidade , Talassemia delta/sangue , Talassemia delta/mortalidade
2.
Z Geburtshilfe Neonatol ; 224(3): 150-152, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31842240

RESUMO

Fetomaternal hemorrhage (FMH) is usually detected by either the Kleihauer-Betke (KB) test or by 2 cytometry, the latter of which represents the gold standard of FMH diagnosis today. But what do we do when neither method is available? We present two cases of suspected FMH due to their characteristic signs and symptoms that were ultimately confirmed by hemoglobin electrophoresis (HE).


Assuntos
Eletroforese Capilar/métodos , Transfusão Feto-Materna/diagnóstico , Feminino , Hemoglobina Fetal/análise , Hemoglobinas , Humanos , Gravidez
3.
Hemoglobin ; 43(4-5): 277-279, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31530045

RESUMO

We report a de novo heterozygous variant of the ß-globin chain that showing a mild ß-thalassemia intermedia (ß-TI) phenotype. He presented with mild anemia, splenomegaly, reticulocytosis, and poikilocytosis and tear drop cells on the blood smear; Immune mediated hemolysis, red cell membrane and enzyme defects, were excluded; hemoglobin (Hb) electrophoresis showed an elevation of Hb F. Molecular analysis of the ß-globin gene showed a heterozygous variation in exon 3 (HBB: c.379delG, p.Val127Cysfs*32) in the absence of an α-globin gene mutation or mutations that modulate Hb F expression.


Assuntos
Mutação , Globinas beta/genética , Talassemia beta/genética , Criança , Hemoglobina Fetal/análise , Hemoglobinas Anormais/genética , Heterozigoto , Humanos , Masculino , Fenótipo , Turquia
5.
Arch Pathol Lab Med ; 143(12): 1539-1544, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31173529

RESUMO

CONTEXT.­: The Kleihauer-Betke (KB) test is validated for estimating the dose of Rh immune globulin needed for Rh-negative pregnant females. However, some clinicians are also ordering the test for Rh-positive women. The degree to which this practice occurs is unknown. OBJECTIVE.­: To evaluate the number of laboratories that perform the KB test on Rh-positive pregnant women, and to establish current ordering practices for this indication. DESIGN.­: We added 9 supplemental questions regarding KB test use for fetomaternal hemorrhage to the 2016 College of American Pathologists proficiency test survey. We also reviewed the available literature regarding the diagnostic utility of the KB test for Rh-positive women. RESULTS.­: A total of 1578 surveys were evaluated and revealed that 52% (824) of respondents perform these tests for Rh-positive women, and more than 50% (440 of 819; 53.7%) of these laboratories report that the results for Rh-positive women are treated as important or very important. CONCLUSIONS.­: The KB test is commonly used for Rh-positive women, and the information obtained from the test is considered as urgent and important. However, the available literature in support of this practice is still nonconclusive.


Assuntos
Hemoglobina Fetal/análise , Transfusão Feto-Materna/diagnóstico , Testes Hematológicos/métodos , Laboratórios/estatística & dados numéricos , Feminino , Humanos , Gravidez , Sistema do Grupo Sanguíneo Rh-Hr , Inquéritos e Questionários
6.
Hemoglobin ; 43(2): 140-144, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31190573

RESUMO

We report a rare case of hereditary spherocytosis (HS) and hereditary persistence of fetal hemoglobin (Hb) (HPFH) complicated with a ß-thalassemia (ß-thal) trait and a Krüppel-like factor 1 (KLF1) gene mutation misdiagnosed as ß-thal intermedia (ß-TI) due to a high percentage of Hb F. The proband presented with pale skin, jaundice and splenomegaly. Analysis of the thalassemia gene indicated ßcodon 17/ßA (HBB: c.52A>T), while Hb analysis showed significantly increased Hb F levels. The proband was diagnosed to carry ß-TI, and a blood transfusion regimen together with iron chelation treatment was recommended. Due to the difference between the phenotype and genotype, next generation sequencing (NGS) was performed and the proband was found to carry a homozygous mutation on the SPTB gene combined with a heterozygous mutation in KLF1. An eosin-5-maleimide binding test (EMA-BT) showed that the mean fluorescence intensity decreased by 47.1%. The proband was finally diagnosed with HS and HPFH complicated with a ß-thal trait and the high percentage of Hb F was believed to be ascribed to the KLF1 gene mutation, which is frequent in areas where thalassemia is prevalent. For patients with a ß gene mutation accompanying significantly high percentage of Hb F, the diagnosis of ß-TI could be warranted, and the influence of the KLF1 gene mutation should be carefully excluded to avoid misdiagnosis of other types of hereditary hemolytic diseases.


Assuntos
Erros de Diagnóstico , Hemoglobina Fetal/análise , Fatores de Transcrição Kruppel-Like/genética , Mutação , Espectrina/genética , Esferocitose Hereditária/diagnóstico , Talassemia beta/diagnóstico , Sequenciamento de Nucleotídeos em Larga Escala , Homozigoto , Humanos
7.
J Pediatr Hematol Oncol ; 41(4): 303-306, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30676434

RESUMO

BACKGROUND AND AIM: Thalassemia screening instructions in Iran categorizes couples with mean corpuscular volume (MCV)=75 to 80, mean corpuscular hemoglobin (MCH)=26 to 27, hemoglobin A2 (HbA2)<3.5, and hemoglobin fetal (HbF)<3 indices as low-risk couples, and therefore further genetic testing is not obligatory. This study examined the possibility of classifying couples with MCH<26 and MCV≥80 indices in the low-risk group when their HbF was <3 and HbA2 was <3.2. METHODOLOGY: This was a cross-sectional study. The data included results from cell blood count and HbA2 prenatal diagnosis (PND) and HbF tests taken by 22 health care centers in Esfahan province, central Iran, throughout the years 2012-2016. The inclusion criterion was the registering of MCV, MCH, and PND results of the participants. From the 5804 participants, 5624 individuals were included in the study. RESULTS: The sensitivity and specificity of the screening program were 99.7 and 53.12, respectively. Ten cases (0.18%) with thalassemia trait had indices MCV≥80 and MCH≥26 including 3 cases (0.05%) with concurrent α and ß-thalassemia mutations and 7 cases (0.12%) with HbS mutations. Altogether, 553 subjects (9.83%) had MCV≥80 and MCH<26 indices, and only 1 case (0.018%) was found with ß-thalassemia mutations (codon8 (-AA)/WT genotype). CONCLUSIONS: Subjects with MCV≥80, MCH<26, HbA2<3.2, and HbF<3 cell blood count indices could be grouped as low-risk couples if normal HbA2 and HbF values are considered. The results of this study also indicate that there is a chance of missing concurrent α and ß-thalassemia or HbS hemoglobinopathies in the current screening program given the fact that genetic testing is not considered for couples with MCV and MCH in the low-risk range. HbF testing could be conducted to prevent these missing cases.


Assuntos
Índices de Eritrócitos , Hemoglobina Fetal/análise , Testes Hematológicos/métodos , Hemoglobina A2/análise , Talassemia beta/sangue , Adulto , Estudos Transversais , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Fatores de Risco , Sensibilidade e Especificidade , Talassemia beta/genética
8.
Blood Cells Mol Dis ; 75: 30-34, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30597429

RESUMO

BACKGROUND: Sickle cell disease (SCD) is a Mendelian single gene disorder with highly variable phenotypic expression. In the present study, we analyzed the influence of HbF, alpha thalassemia and other hematological indices to determine their association with acute pain episodes. METHOD: This case control study consisted of SCD subjects with HbS phenotype experiencing three or more acute pain episodes in last twelve months (cases) and without any episode of acute pain during last twelve months (controls). Hematological parameters, HbF, and presence of alpha thalassemia were assessed in all subjects. RESULTS: A statistically significant difference between HbF levels (P < 0.025, χ2 test) and alpha thalassemia (P < 0.008, χ2 test) was observed between controls and cases group. Univariate analysis indicated that increased HbF levels > 25% (OR: 0.37, 95% CI: 0.18-0.77, P < 0.008) and presence of alpha thalassemia (OR: 0.53, 95% CI: 0.33-0.85, P < 0.009) provided protection, while multivariate analysis revealed significant protection was attributable only by higher HbF levels (OR: 0.39, 95% CI: 0.17-0.88, P < 0.025). Significantly higher HbF levels were observed only in the 11-20 age group of cases in comparison to controls (Student's t-test, P < 0.001). CONCLUSION: Higher concentrations of HbF are associated with protection against frequent episodes of acute pain crisis in SCD patients.


Assuntos
Dor Aguda/etiologia , Anemia Falciforme/sangue , Hemoglobina Fetal/análise , Adolescente , Anemia Falciforme/complicações , Estudos de Casos e Controles , Criança , Feminino , Humanos , Masculino , Adulto Jovem , Talassemia alfa
9.
Lab Med ; 50(2): 158-162, 2019 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-30239825

RESUMO

OBJECTIVE: To establish a simple formula to be used for discrimination between ß-thalassemia/hemoglobin E (ß-thal/HbE) and homozygous hemoglobin (Hb)E in specimens with absent hemoglobin (Hb)A, HbE of greater than 75%, and HbF between 5% and 15%. METHODS: We analyzed laboratory results from February 2015 through February 2018. Molecular analysis for diagnosis of ß-thal mutation and HbE was performed in specimens that contained HbE of greater than 75% and HbF from 5% to 15%, as measured by high-performance liquid chromatography (HPLC). HbA2 and HbF levels were also measured by capillary electrophoresis. Then, the formula (6 × HbA2 + HbF)/MCV was developed. RESULTS: The score of 0.9 or higher was found in all 19 ß-thal/HbE specimens (100%) and only 8 of 65 homozygous HbE specimens (12.3%). Also, the formula yielded 90.5% efficiency in identifying ß-thal/HbE disease, and the efficiency was found to be higher compared with when the HbA2 value of greater than 6% was used by itself (85.4%). CONCLUSION: The formula (6 × HbA2 + HbF)/MCV, with a cutoff point at 0.9, could identify the potential cases of ß-thal/HbE disease among patients with absent HbA, HbE of greater than 75%, and HbF between 5% and 15%.


Assuntos
Hemoglobina Fetal/análise , Hemoglobina E/análise , Talassemia beta/sangue , Talassemia beta/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Cromatografia Líquida de Alta Pressão , Eletroforese Capilar , Índices de Eritrócitos/fisiologia , Feminino , Hematócrito , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Talassemia beta/epidemiologia
10.
Ann Lab Med ; 39(2): 133-140, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30430775

RESUMO

BACKGROUND: Thalassemia is highly prevalent in Southeast Asia but is rare in Korea; however, Southeast Asian immigrant population is recently rising in Korea. We investigated the prevalence of thalassemia in Korea in the context of increasing immigration. METHODS: This prospective, observational, multicenter study was conducted between September 2015 and August 2017. A total of 669 subjects <30 years living in Korea were grouped into the multiethnic (N=314) and Korean (N=355) groups. Hb electrophoresis and complete blood count (CBC) were performed. If low mean corpuscular volume with high red blood cell distribution width coefficient of variation or a high fetal Hb (HbF) or Hb alpha 2 (HbA2) level was observed, genetic testing of the α- and ß-globin genes was performed. In addition, the number of potential thalassemia carriers in Korea was estimated by multiplying the prevalence of thalassemia in a specific ethnicity by the number of immigrants of that ethnicity. RESULTS: Twenty-six multiethnic and 10 Korean subjects showed abnormal results for Hb electrophoresis and CBC. Eighteen multiethnic subjects and four Korean subjects were tested for α-globin and ß-globin gene mutations. Within the multiethnic group, five subjects (1.5%) were α-thalassemia carriers, and six (1.9%) were ß-thalassemia minor. The SEA deletion in HBA1 and HBA2, and c. 126_129delCTTT (p.Phe42Leufs*19) mutation of HBB were the dominant inherited mutations. CONCLUSIONS: The prevalence of thalassemia in young people in Korea is increasing due to the increasing number of Southeast Asian immigrants.


Assuntos
Emigração e Imigração , Talassemia/diagnóstico , Adolescente , Adulto , Contagem de Células Sanguíneas , Criança , Pré-Escolar , Eletroforese , Feminino , Hemoglobina Fetal/análise , Hemoglobina Fetal/genética , Deleção de Genes , Testes Genéticos , Hemoglobina A2/análise , Hemoglobina A2/genética , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Prospectivos , República da Coreia/epidemiologia , Talassemia/epidemiologia , Talassemia/etnologia , Adulto Jovem
11.
Bull Soc Pathol Exot ; 112(4): 206-212, 2019.
Artigo em Francês | MEDLINE | ID: mdl-32003197

RESUMO

The objective of this study is to reduce the morbidity of children with homozygous sickle cell disease presenting severe forms. We have conducted a longitudinal study between November 2015 and September 2017 at the Brazzaville University Hospital. Children with sickle cell disease requiring treatment with hydroxyurea were included. The variables studied were therapeutic compliance, evolutive profile of nutritional status, indications of hydroxyurea, electrophoresis of hemoglobin, blood count, and toxicity. The statistical test used was Student test with a significance threshold of less than 0.05. One thousand twenty-four children were monitored for sickle cell disease, 107 of which had received hydroxyurea (10.4%). The indications for hydroxyurea were recurrent anemic attacks (≥ 4) in 62 cases (57.9%), neurological crises 19 cases (17.8%), recurrent hyperalgesic crises in 17 cases (15.9%), priapism in 4 cases (3.7), and acute thoracic syndrome in 2 cases (1.9%). Therapeutic compliance was good in 89.5% of them. A rapid and lasting clinical improvement was noted in the majority of patients with hyperalgesic attacks (88.2%) and anemic attacks (88.7%), two recurrences for the cerebrovascular accidents, and an absence of recurrence of priapism and of the acute thoracic syndrome. From the biological point of view, there was a significant increase in fetal hemoglobin (1.2 to 16.2%; P  < 0.05), hemoglobin (7 to 8.3 g/dl; P < 0.05), mean cell volume (80.8 to 96 fl; P  < 0.05) and a significant decrease in mean white blood cell count (15,633 to 9,872/mm3; P  < 0.05) and platelets (387,002 to 324,400/mm3; P  < 0.05). The signs of toxicity observed were mainly vomiting and thrombocytopenia in two cases each, one case with headache and the other with neutropenia. Indications for use of hydroxyurea therapy in children with sickle cell disease in Brazzaville are common. These are dominated by recurrent anemic seizures, strokes, and hyperalgesic seizures. The excellent evolution of these complications under hydroxyurea represents an interesting alternative in our countries with limited resources.


Assuntos
Anemia Falciforme/tratamento farmacológico , Hidroxiureia/uso terapêutico , Adolescente , Anemia/etiologia , Anemia/prevenção & controle , Anemia Falciforme/complicações , Contagem de Células Sanguíneas , Criança , Pré-Escolar , Congo , Feminino , Hemoglobina Fetal/análise , Homozigoto , Humanos , Hidroxiureia/efeitos adversos , Hiperalgesia/etiologia , Hiperalgesia/prevenção & controle , Estudos Longitudinais , Masculino , Doenças do Sistema Nervoso/etiologia , Doenças do Sistema Nervoso/prevenção & controle , Priapismo/etiologia , Priapismo/prevenção & controle , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle
12.
Sci Rep ; 8(1): 16794, 2018 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-30429489

RESUMO

Sickle cell disease (SCD) is an inherited blood disorder associated with severe anemia, vessel occlusion, poor oxygen transport and organ failure. The presence of stiff and often sickle-shaped red blood cells is the hallmark of SCD and is believed to contribute to impaired blood rheology and organ damage. Most existing measurement techniques of blood and red blood cell physical properties require sample contact and/or large sample volume, which is problematic for pediatric patients. Acoustic levitation allows rheological measurements in a single drop of blood, simultaneously eliminating the need for both contact containment and manipulation of samples. The technique shows that the shape oscillation of blood drops is able to assess blood viscosity in normal and SCD blood and demonstrates an abnormally increased viscosity in SCD when compared with normal controls. Furthermore, the technique is sensitive enough to detect viscosity changes induced by hydroxyurea treatment, and their dependence on the total fetal hemoglobin content of the sample. Thus this technique may hold promise as a monitoring tool for assessing changes in blood rheology in sickle cell and other hematological diseases.


Assuntos
Anemia Falciforme/sangue , Viscosidade Sanguínea , Eritrócitos Anormais/patologia , Reologia/métodos , Anemia Falciforme/diagnóstico , Viscosidade Sanguínea/efeitos dos fármacos , Hemoglobina Fetal/análise , Humanos , Hidroxiureia/farmacologia , Reologia/normas , Som
13.
Hemoglobin ; 42(3): 161-165, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-30205725

RESUMO

Krüppel-like factor 1 (KLF1) is a pleiotropic erythroid transcription factor that is a regulator of definitive erythropoiesis. The aim of this study was to detect KLF1 gene variants in α-thalassemia (α-thal) carriers with an increased Hb F level in a Chinese population, and determine the changes of hematological parameters as a result of interactions between KLF1 gene mutations and α-thal. Subjects with α-thal and Hb F levels of ≥1.0% were selected for further investigation. Direct sequencing was used to detect KLF1 gene mutations. Hematological parameters of subjects with α-thal and concomitant KLF1 gene mutations and those with α-thal alone were compared. The KLF1 gene variants were detected in 46 of 275 (16.7%) individuals with α-thal and Hb F levels of ≥1.0%. The detection rate of KLF1 gene mutations rose correspondingly when the Hb F level increased. For α0-thal carriers, significantly lower mean corpuscular volume (MCV) and mean corpuscular hemoglobin (Hb) (MCH) values were observed in KLF1 gene mutation-positive carriers than that in KLF1 gene mutation-free carriers; conversely, significantly higher Hb A2 and Hb F levels were observed in the former condition rather than in the latter condition. The results of this study indicate that KLF1 gene variants are common in Chinese subjects with α-thal and increased Hb F levels, and KLF1 gene mutations decreased the red blood cell (RBC) indices in α-thal carriers as that in normal adults.


Assuntos
Hemoglobina Fetal/análise , Fatores de Transcrição Kruppel-Like/genética , Talassemia alfa/genética , Grupo com Ancestrais do Continente Asiático/genética , Índices de Eritrócitos , Feminino , Variação Genética , Hemoglobina A2/análise , Heterozigoto , Humanos , Masculino , Mutação , Talassemia alfa/epidemiologia
14.
Hemoglobin ; 42(2): 84-90, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30200838

RESUMO

Hemoglobinopathies evolved as a protective mechanism against malaria, which exhibit selective advantage in the heterozygous state. However, in a homozygous recessive condition, it poses a serious socioeconomic burden. Sickle cell anemia is an autosomal recessive hemoglobinopathy associated with erythrocytes sickling, vaso-occlusive crisis (VOC), as well as multi-organ failure and death. The coinheritance of other hemoglobinopathies is known to substantially modulate the clinical manifestation of sickle cell anemia. In the present study, we aimed to analyze the coinheritance of ß-thalassemia (ß-thal) in Hb S (HBB: c.20A>T) patients. The study includes 918 sickle cell anemia patients from 10 ethnic populations of Chhattisgarh State, India. Complete blood counts (CBCs) and hemoglobin (Hb) high performance liquid chromatography (HPLC) fractionation data were collected from patient record books. We observed Hb S-ß-thal in all the analyzed populations. Interestingly, high frequencies of Hb S-ß-thal have been observed in Satnami (53.8%), Rawat (47.1%), Gond (35.1%) and Panika (30.6%) populations. Inter-population comparison of hematological parameters [Hb F (p < 0.001), Hb A2 (p < 0.001), Hb (p = 0.03) and red blood cell distribution width (RDW) (p < 0.001)] revealed significant differences. We also observed that mean Hb F levels were significantly higher in Hb S compared to Hb S-ß-thal patients in the respective populations. Our study highlights the higher prevalence of ß-thal as well as the compound heterozygosity for Hb S and ß-thal in various populations of Chhattisgarh State, India.


Assuntos
Anemia Falciforme/genética , Hemoglobina Falciforme/genética , Heterozigoto , Talassemia beta/genética , Hemoglobina Fetal/análise , Hemoglobina Falciforme/análise , Humanos , Índia/epidemiologia , Talassemia beta/epidemiologia
17.
Clin Lab ; 64(7): 1305-1309, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30146834

RESUMO

BACKGROUND: Hb I and Hb Shaare Zedek are rare hemoglobin variants in the Chinese population. High-performance liquid chromatography (HPLC) is a widely used technique for screening of thalassemias and hemoglobin variants in Chinese primary hospitals. However, some rare hemoglobin variants cannot be effectively separated by HPLC. Here, we report one case of Hb I and one case of Hb Shaare Zedek which could not be detected by HPLC but required capillary electrophoresis (CE) in our hospital. METHODS: Two blood samples with high Hb F level were analyzed by HPLC as part of routine screening, and then globin genes were analyzed using Gap-PCR, PCR-Reverse dot-blot (RDB), and DNA sequencing. Subsequently, samples were analyzed by CE and results compared to HPLC. RESULTS: In case 1, results were as follows: Hb F 16.9%, Hb A0 72.5% (failed to show the value of Hb A in HPLC) and Hb A2 2.2% for HPLC. No mutations were detected using Gap-PCR and PCR-RDB, but there was a mutation of codon (CD) 16 in the α2 globin gene (AAG>GAG, corresponds to Hb I) by DNA sequencing. CE showed Hb A2 1.9%, Hb A 74%, Hb I 24.1%. In case 2, results were as follows: Hb F 11.0%, Hb A0 76.6%, and Hb A2 4.7% for HPLC. It showed a CD 41 - 42 mutation of the ß-globin gene (-TTCT) using PCR-RDB and the CD 56 mutation in α2/α1 globin gene (AAG>GAG, corresponding to Hb Shaare Zedek) with DNA sequencing. CE displayed Hb A2 4.5%, Hb A 84.6%, Hb F 0.4%, Hb Shaare Zedek 10.5%. CONCLUSIONS: Hb I and Hb Shaare Zedek cannot be separated by HPLC because of co-elution with Hb F. However, they were identified and quantified using CE. As a general precaution, therefore, and owing to the existence of rare variants that may co-elute with normal hemoglobin fractions, it is recommended to use at least two complementary methods for the diagnostic detection of hemoglobin species.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Eletroforese Capilar/métodos , Hemoglobinopatias/diagnóstico , Hemoglobinas Anormais/análise , Sequência de Bases , Hemoglobina Fetal/análise , Hemoglobina Fetal/genética , Hemoglobina A/análise , Hemoglobina A/genética , Hemoglobina A2/análise , Hemoglobina A2/genética , Hemoglobinopatias/sangue , Hemoglobinopatias/genética , Hemoglobinas Anormais/genética , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
Am J Hematol ; 93(11): 1411-1419, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30132969

RESUMO

In order to identify very early prognostic factors that can provide insights into subsequent clinical complications, we performed a comprehensive longitudinal multi-center cohort study on 57 infants with sickle cell anemia (55 SS; 2 Sß°) during the first 2 years of life (ClinicalTrials.gov: NCT01207037). Time to first occurrence of a severe clinical event-acute splenic sequestration (ASS), vaso-occlusive (VOC) event requiring hospitalization, transfusion requirement, conditional/ abnormal cerebral velocities, or death-was used as a composite endpoint. Infants were recruited at a mean age of 4.4 ±1 months. Median follow-up was 19.4 months. During the study period, 38.6% of infants experienced ≥1 severe event: 14% ASS, 22.8% ≥ 1 VOC (median age: 13.4 and 12.8 months, respectively) and 33.3% required transfusion. Of note, 77% of the cohort was hospitalized, with febrile illness being the leading cause for admission. Univariate analysis of various biomarkers measured at enrollment showed that fetal hemoglobin (HbF) was the strongest prognostic factor of subsequent severe outcome. Other biomarkers measured at enrolment including absolute neutrophil or reticulocyte counts, expression of erythroid adhesion markers, % of dense red cells, cellular deformability or ϒ-globin genetic variants, failed to be associated with severe clinical outcome. Multivariate analysis demonstrated that higher Hb concentration and HbF level are two independent protective factors (adjusted HRs (95% CI) 0.27 (0.11-0.73) and 0.16 (0.06-0.43), respectively). These findings imply that early measurement of HbF and Hb levels can identify infants at high risk for subsequent severe complications, who might maximally benefit from early disease modifying treatments.


Assuntos
Anemia Falciforme/diagnóstico , Índice de Gravidade de Doença , Anemia Falciforme/complicações , Anemia Falciforme/terapia , Biomarcadores/análise , Transfusão de Sangue , Estudos de Coortes , Feminino , Hemoglobina Fetal/análise , Hemoglobinas/análise , Hospitalização , Humanos , Lactente , Estudos Longitudinais , Masculino , Prognóstico
19.
J Immunoassay Immunochem ; 39(3): 323-336, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29985765

RESUMO

Hemoglobin F (HbF) in blood lysate can be accurately measured by various methods, including immunoassay. In this study, we have produced polyclonal antibody (pAb) against HbF and established a modified sandwich-type ELISA for HbF quantification in blood lysates. The modified sandwich ELISA utilized anti-γ-globin monoclonal antibody clones Thal N/B as the capture antibody (Ab) coated on solid-phase, fluorescein isothiocyanate (FITC)-labeled pAb as the detecting Ab, and HPR-labeled anti-FITC Ab as the signal-generating Ab. By using an optimized blood lysate dilution, the HbF could be measured with no interference from hemoglobin Bart's (Hb Bart's) and hemoglobin Portland (Hb Portland 1) presented in α-thalassemia carriers. HbF levels measured by the modified sandwich ELISA were comparable to those quantified by the standard cation-exchange high performance liquid chromatography. We suggested that this modified sandwich ELISA was able to accurately measure HbF levels even in α-thalassemia carriers containing Hb Bart's and Hb Portland 1 and be an alternative method for HbF measurement.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Hemoglobina Fetal/análise , Hemoglobinas Anormais/análise , Talassemia alfa/sangue , Talassemia alfa/diagnóstico , Animais , Humanos , Coelhos
20.
Hemoglobin ; 42(2): 138-140, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29745271

RESUMO

The major hemoglobin (Hb) during fetal life is fetal Hb (Hb F). It is mostly replaced by adult Hbs before birth and during the first year of life. In adults, where Hb F comprises <2.0% of the total Hb, it is not homogenously distributed among the red blood cells (RBCs) but is concentrated in a few RBCs, termed F-cells. Interestingly, for reasons that are unclear, Hb F increases in the maternal circulation during pregnancy. This increased Hb F could have two potential origins that are not mutually exclusive: A) maternal origin, due to inducing environment of Hb F in the maternal erythroid precursors; B) fetal origin, due to fetal cells crossing the placenta and entering the maternal circulation. The question we present herein is whether the observed increased Hb F in the maternal circulation during pregnancy is, at least partially, derived from the fetal origin. Peripheral blood was obtained from normal neonates (1-3 days old), adult men and pregnant and non pregnant women. The RBCs were stained for Hb F and carbonic anhydrase (CA) using a fetal cell count kit and analyzed by flow cytometry. Fetal and adult F-cells were distinguished by their expression of Hb F and CA. Fetal F-cells were Hb F++/CA-, while adult F-cells were Hb F+/CA+. Comparing pregnant and non pregnant women samples (n = 10), we found six samples of pregnant women with 0.2-1.7% fetal cells, but none in the non pregnant group. These results support the possibility that at least part of the increase in Hb F during pregnancy is due to fetal cells entering the maternal circulation.


Assuntos
Hemoglobina Fetal/análise , Transfusão Feto-Materna , Adulto , Eritrócitos/química , Feminino , Sangue Fetal/citologia , Humanos , Recém-Nascido , Masculino , Gravidez
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