Hemoglobina Denver, una causa de desaturación en oximetría de pulso. Reporte de caso en un paciente pediátrico / Hemoglobin Denver, a cause of desaturated pulse oximetry. A pediatric case report

Las hemoglobinopatías son trastornos genéticos que afectan a la molécula de hemoglobina (Hb). Las mutaciones en las cadenas a o b que alteran el tetrámero de Hb pueden modificar la capacidad de la molécula para unirse al oxígeno. Las hemoglobinopatías con baja afinidad al oxígeno pueden presentarse con cianosis y una lectura alterada de la oximetría de pulso, lo que lleva a pruebas innecesarias y, a veces, invasivas para descartar afecciones cardiovasculares y respiratorias. En el siguiente reporte de caso, presentamos a una paciente pediátrica, asintomática, que se presentó a la consulta por detección de desaturación en oximetría de pulso. Las pruebas de laboratorio iniciales mostraron una anemia normocítica, normocrómica. Las muestras de gas venoso demostraron una p50 elevada. Después de extensas herramientas de diagnóstico, se diagnosticó una variante de Hb con baja afinidad al oxígeno, Hb Denver.

Hemoglobinopathies are genetic disorders that affect the hemoglobin (Hb) molecule. Mutations in the alpha or beta chains altering the Hb tetramer may modify the molecule's oxygen-binding capacity. Hemoglobinopathies with low oxygen affinity may occur with cyanosis and an altered pulse oximetry reading, leading to unnecessary and sometimes invasive tests to rule out cardiovascular and respiratory conditions. In the case report described here, we present an asymptomatic pediatric patient who consulted for desaturated pulse oximetry. Her initial laboratory tests showed normocytic, normochromic anemia. Venous blood gas samples showed an elevated p50. After using extensive diagnostic tools, a variant of Hb with low oxygen affinity was diagnosed: Hb Denver.

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.

Genetic analysis of a child with Hemoglobin Santa Ana / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic basis for a child with Hemoglobin Santa Ana (Hb Santa Ana).@*METHODS@#The child was admitted to the Children's Hospital of Chongqing Medical University on August 4, 2013 due to anemia, splenomegaly and deepening urine color for 5 years. His clinical data were collected. Peripheral blood samples of the child and his parents were collected for routine blood test. The erythrocyte parameters of the child and his parents were determined with an automatic hemocyte analyzer. The hemoglobin components of the child and his parents were detected by high-performance liquid chromatography (HPLC). Common mutations associated with thalassemia were detected by Gap-PCR and PCR-reverse dot blotting (PCR-RDB). Rare variants of the globin genes were detected by next generation sequencing (NGS), and the result was verified by Sanger sequencing.@*RESULTS@#The child has shown mild to moderate hemolytic anemia. Routine blood test showed that he had lower hemoglobin (90 g/L) and mean corpuscular hemoglobin concentration (267 g/L) but a higher reticulocyte ratio (0.141), which indicated hypopigmented hyperplastic anemia. Analysis of hemoglobin component showed that his hemoglobin F was elevated to 10.7%, which indicated abnormal synthesis of β globin peptide chain. HPLC analysis showed an abnormal peak accounting for 4.5% of the total area. Neither of his parents was found to have abnormal results for routine blood test and hemoglobin component analysis. No common globin gene variant was detected in the child. Gene sequencing revealed that the child has harbored a heterozygous variant of HBB: c.266T>C, which was de novo in origin. Based on the guidelines of American College of Medical Genetics and Genomics, the variant was predicted to be pathogenic.@*CONCLUSION@#The heterozygous HBB: c.266T>C variant probably underlay the hemolytic anemia associated with Hb Santa Ana in this patient.

Clinical Diagnosis and Prenatal Screening of Hb Lepore-BW Associated with IVS-II-654 Heterozygous Mutation / 中国实验血液学杂志

OBJECTIVE@#To identify one case of rare Hb Lepore-BW associated with IVS-II-654 heterozygous mutation in Sichuan area.@*METHODS@#The blood routine examination and hemoglobin electrophoresis methods were used to analyze the blood routine parameters, HbA2 and HbF in the samples of peripheral blood in proband and his parents, as well as the cord blood of pregnant woman. The detection of thalassemia gene and Sanger sequencing methods were used to detect the hemoglobin mutations.@*RESULTS@#The result showed that the Hb Lepore-BW heterozygous mutation was detected in the father of the proband, while a rare Hb Lepore-BW with IVS-II-654 heterozygous mutation was detected in the proband, as well as his mother and cord blood were both detected as IVS-II-654 heterozygous mutation.@*CONCLUSION@#The study identified a rare Hb Lepore-BW with IVS-II-654 heterozygous mutation, which was characterized by intermediate β-thalassemia. It is necessary to hemoglobin electrophoresis combined with routine blood testing in prenatal screening.

Hematologic Phenotype and Genotype Analysis of Patients with Hemoglobin Variants / 中国实验血液学杂志

OBJECTIVE@#To study the hematologic and molecular features of 14 patients with hemoglobin (Hb) variants, so as to provide reference data for its laboratory screening.@*METHODS@#A total of 1 029 samples were screened by high performance liquid chromatography (HPLC) on the Bio-Rad VariantⅡHPLC system. GAP-PCR and reverse dot blot (RDB) were used to detect common mutation of α and β globin gene in Chinese. DNA sequencing for α and β globin gene was simultaneously performed in samples with abnormal spectrum peak and negative thalassemia gene.@*RESULTS@#In 1 029 samples, 10 types of structural Hb variants were detected in14 cases (1.36%), including 1 case of Hb E / β- thalassemia, 1 case of Hb E /α- thalassemia (HbH disease), 2 cases of HbG-Taipei, 2 cases of Hb Q-Thailand, 2 cases of Hb Youngstown, 1 case of Hb Guangzhou-Hangzhou, 1 case of Hb M-Boston, 1 case of Hb G-Siriraj, 1 case of Hb J-Baltimore, 1 case of Hb J-Sicilia and 1 case of Hb Tamano.@*CONCLUSION@#The occurrence of abnormal structural Hb variants with many genotypes in Shanghai is unique. Except for Hb E, Hb Youngstown, and Hb M-Boston, other types of heterozygous are normal in phenotypes, and symptoms such as hemolysis and anemia often occur when other diseases are combined.

Genetic Effect Analysis of β-globin Gene 3'UTR+101G>C (HBB:c. *233G>C) Variant / 中国实验血液学杂志

OBJECTIVE@#To investigate whether β-globin gene 3'UTR+101G>C (HBB:c.*233G>C) variant has genetic effect and provide basis for gene diagnosis and genetic counseling.@*METHOD@#Whole blood cell analysis and capillary zone electrophoresis (CZE) were used to analyze the hematological indexes. The most frequent 23 mutations in southern Chinese individuals were routinely measured by PCR-flow fluorenscence immunmicrobeads assay. Sanger sequencing was used to detect the other variants of β-globin gene (HBB).@*RESULTS@#In 463 cases, a total of 7 cases with HBB:c.*233G>C variant were detected, among them 4 cases carried other pathogenic variants of HBB gene (2 cases were in trans, 2 cases were in cis), who had typical hematological characteristics of mild β-thalassemia, and 3 cases also carried abnormal hemoglobin variation, but did not have hematological characteristics of β-thalassemia.@*CONCLUSION@#The study shows that HBB:c.*233G > C variant has no obvious genetic effect and should be a benign polymorphism.

Hb Bart's Quantitative Analysis in the Screening of α-Thalassemia / 中国实验血液学杂志

OBJECTIVE@#To research the relationship between difference types of α-thalassemia gene types and Hb Bart's hemoglobin bands.@*METHODS@#Capillary electrophoresis was used to screen thalassemia gene for the newborn form January 2020 to December 2020, and the thalassemia gene was detected by PCR or PCR-NGS in the positive patients. The relationship between α-thalassemia gene and Hb Bart's hemoglobin was compared and analyzed statistically.@*RESULTS@#There were significant differences in Hb Bart's hemoglobin among the different α-thalassemia mutation types, Hb Bart's was the highest in --SEA/-α@*CONCLUSION@#The Hb Bart's content of different genotypes of α-thalassemia are significantly different. The Hb Bart's content shows high application value in α-thalassemia screening and genotyping identification.

Application of Next-Generation Sequencing in Screening of Thalassemia Gene in 11212 Pregnant Women in Suxian and Beihu Districts of Chenzhou City, Hunan Province / 中国实验血液学杂志

OBJECTIVE@#To understand the carrying rate, gene mutation frequency and composition ratio of thalassemia in pregnant women in Suxian and Beihu districts of Chenzhou, Hunan Province.@*METHODS@#Thalassemia gene in 11 212 samples was analyzed by using Next-Generation Sequencing.@*RESULTS@#Among the 11 212 samples, 938 were diagnosed as thalassemia, in which 618 (5.51%) were diagnosed as α-thalassemia, 268 (2.39%) as β-thalassemia, 29（0.26%）as abnormal hemoglobin and 23 (0.21%) as αβ-thalassemia. The gene mutations of --SEA /αα(40.29%) and -α3.7/αα(37.7%) in α-thalassemia were the most common, while for β- thalassemia, the most commonly gene mutation were β41-42M/βN(24.26%) and β654M/βN(23.88%). The detection rate of rare type α,β-thalassemia gene was 0.19%(21/11 212）, 0.53%（59/11 212）, respectively.@*CONCLUSION@#The carrying rate of thalassemia in pregnant women is 8.37% in Suxian and Beihu districts of Chenzhou city, and the genotypes are complex. Next-Generation Sequencing can detect rare thalassemia genes and new gene mutations effectively.

Analysis of phenotypes of Hb J-Bangkok and concomitant thalassemia / 中华医学遗传学杂志

OBJECTIVE@#To analyze the hematological phenotypes of Hb J-Bangkok and concomitant thalassemia.@*METHODS@#In total 72 397 samples were screened by using capillary electrophoresis. Samples with Hb J-Bangkok were identified by DNA sequencing and analysis of red blood cell parameters. Gap-PCR and PCR-reverse dot blotting (PCR-RDB) were used for analyzing the thalassemia genes.@*RESULTS@#Thirty one cases of Hb J-Bangkok were identified, all of which were heterozygotes. The hematological phenotype index (Hb, mean corpuscular volume, mean corpuscular hemoglobin, Hb J-Bangkok, Hb A@*CONCLUSION@#Hb J-Bangkok heterozygotes have normal hematological phenotypes, though they may show different hematological characteristics when concomitant with different types of thalassemia, for which genetic counseling should be provided accordingly.

Analysis of 34 800 cases of Abnormal Hemoglobinopathy in Couples of Child-bearing Age in Chongqing Area / 中国实验血液学杂志

OBJECTIVE@#To explore the abnormal hemoglobinopathy in couples of child-bearing age in Chongqing.@*METHODS@#A total of 34 800 subjects of child-bearing age were screened for thalassemia by using capillary electrophoresis from January 2015 to September 2018. PCR-flow cytometry fluorescence hybridization assay was used to detect the common thalassemia gene deletions and mutations.@*RESULTS@#8 kinds of abnormal hemoglobinopathy were detected in 200 cases from 34 800 subjects of child-bearing age, the detection rate was 0.57% in couples of child-bearing age in Chongqing: Among 200 cases of abnormal hemoglobin pathy, Hb E was found in 90 cases (accounting for 45.0%), and Hb D in 25 cases (accounting for 12.5%). Hb NewYork was found in 25 cases (accounting for 12.5%). HbJ-bangkok was found in 25 cases (accounting for 12.5%), and Hb Q-Thailand in 16 cases (accounting for 8.0%). Hb Hope was detected in 15 cases (accounting for 7.5%). Hb S was detected in 3 cases (accounting for 1.5%). Hb Hasharon was detected in 1 case (accounting for 0.5%). The mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) of Hb E and Hb Q-Thailand were lower than normal reference intervals.@*CONCLUSION@#The detection rate of abnormal hemoglobinopathy in Chongqing is higher than the average level in China. Capillary electrophoresis can effectively screen abnormal hemoglobinopathy, which is great significant for aristogenesis and improvement of population quality.

Hematological Analysis and Diagnosis of Two Rare Abnormal Hemoglobin / 中国实验血液学杂志

OBJECTIVE@#To analyze the hematological characteristics of Hb Broomhill and Hb Hornchurch, and prenatal diagnosis should be carried out in two families.@*METHODS@#RBC parameters and hemoglobin electrophoretogram were analyzed on the peripheral blood of all patients, and amniotic fluid was collected for prenatal diagnosis. PCR-Flow fluorescent hybridization and Sanger sequencing were performed for gene diagnosis of thalassemia.@*RESULTS@#Three cases of Hb Broomhill were detected, including 2 cases with common SEA α-thalassemia, which was characterized by hypochromic microcytic mild anemia, the capillary electrophoregram revealed a tiny shoulder peak before the Hb A peak; 1 case was diagnosed as Hb Hornchurch combined with β-thalassemia, which also showed mild anemia. Hemoglobin electrophoretogram showed an abnormal hemoglobin variant peak at Hb A@*CONCLUSION@#The carriers of Hb Broomhill and Hb Hornchurch do not have microcytic hypochromic anemia, which do not aggravate the hematological symptoms, such as anemia when being combined with thalassemia of the same type.

Analysis of hematological phenotype and genotype of Hb Q-Thailand in Fujian area / 中华医学遗传学杂志

OBJECTIVE@#To explore the hematological phenotype and genotype of hemoglobin Q-Thailand in Fujian area.@*METHODS@#Genomic DNA was extracted from peripheral venous blood samples of patients. Suspected samples were screened by hematological parameters analysis and verified with DNA sequencing.@*RESULTS@#In 35 patients suspected with Hb Q-Thailand, 20 were confirmed, which included one case compounded with heterozygous β mutation and one compounded with Hb New York.@*CONCLUSION@#Analysis of hematological phenotype and genotype of Hb Q-Thailand can faciliate genetic counseling for patients from Fujian area.

Clinical and genetic analysis of a patient with Hb Ottawa in conjunction with β -thalassemia / 中华医学遗传学杂志

OBJECTIVE@#To analyze the hematological characteristics of a patient with Hb Ottawa in conjunction with β -thalassemia.@*METHODS@#Peripheral blood samples from the proband and her parents were collected and subjected to red blood cell analysis and hemoglobin electrophoresis. Genotypes of α - and β -globin genes were also analyzed.@*RESULTS@#The proband and her mother were both heterozygotes for Hb Ottawa and β -thalassemia variant IVS II-654, and presented with typical β -thalassemia trait featuring hypochromic microcytic anemia. An abnormal hemoglobin band was detected upon electrophoresis.@*CONCLUSION@#Co-existence of Hb Ottawa and β -thalassemia may not aggravate the phenotype.

Quando a HbA1c não é suficiente: um caso de Hemoglobina de Baltimore / When HbA1c is not enough: a case of Baltimore Hemoglobin / Cuando la HbA1c no es suficiente: un caso de Hemoglobina de Baltimore

A hemoglobina A1c (HbA1c) é o gold standard para monitorização da diabetes mellitus. A HbA1c pode estar falsamente diminuída ou aumentada em algumas situações clínicas, como hemoglobinopatias, não traduzindo adequadamente o controle glicêmico. Apresenta-se aqui o caso de um doente com valor de HbA1c incompatível com os registros de glicemia capilar, devido à presença de hemoglobina N-Baltimore. O caso apresentando é relevante porque, apesar de assintomática, a presença desta hemoglobinopatia conduz a uma diabetes falsamente encarada como controlada, se utilizados os métodos de determinação de HbA1c habituais.

The haemoglobin A1c (HbA1c) test is the gold standard in monitoring diabetes mellitus. HbA1c can be falsely decreased or increased in some particular scenarios, as in hemoglobinopathies, inadequately reporting the glycemic control. Here we present the case of a patient with a HbA1c value incompatible with self-monitoring blood glucose levels, due to the presence of hemoglobin N-Baltimore. This case is relevant because, in spite of being asymptomatic, the presence of this type of hemoglobin leads to an incorrect appearance of glycemic control, if standard methods for HbA1c determination are used.

La hemoglobina A1c (HbA1c) es el estándar de oro para la monitorización de la diabetes mellitus. La HbA1c puede estar falsamente disminuida o aumentada en algunas situaciones clínicas, como hemoglobinopatías, no traduciendo adecuadamente el control glucémico. Se presenta aquí el caso de un paciente con valor de HbA1c incompatible con los registros de glucemia capilar, debido a la presencia de hemoglobina N-Baltimore. El caso que presenta es relevante porque, a pesar de asintomática, la presencia de esta hemoglobinopatía conduce a una diabetes falsamente encarada como controlada, si se utilizan los métodos de determinación de HbA1c habituales.

Técnicas convencionales aplicadas al diagnóstico de las hemoglobinopatías / Conventional techniques applied to the diagnosis of hemoglobinopathies / Técnicas convencionais aplicadas ao diagnóstico das hemoglobinopatias

Las hemoglobinopatías son trastornos hereditarios debidos a una gran variedad de defectos que afectan a los genes de globina. El diagnóstico de las hemoglobinopatías resulta de una combinación de estudios clínicos, pruebas de laboratorio y estudio familiar. Las herramientas básicas incluyen hemograma, hemoglobina e índices eritrocitarios (VCM, HCM), morfología de los eritrocitos, recuento de reticulocitos y perfil de hierro. Las determinaciones complementarias son electroforesis de hemoglobina que permite separar las diferentes variantes de acuerdo con su carga eléctrica, cuantificación de hemoglobina A2 (HbA2), Fetal (Hb F), pruebas de solubilidad hemoglobínica y falciformación. Otras técnicas se basan en propiedades fisicoquímicas como la estabilidad de la hemoglobina para detección de variantes inestables. En la práctica las pruebas más útiles son las que permiten detectar la presencia de hemoglobinopatías, como ocurre con la hemoglobina S dejando para laboratorios especializados aquellos procedimientos para identificar la mutación. La correcta detección de los portadores de las diferentes hemoglobinopatías tiene como finalidad dar un consejo genético adecuado sobre la forma de herencia, el riesgo de tener hijos afectados con las formas graves de la enfermedad y evitar tratamientos innecesarios. El diagnóstico molecular se reserva para la alfa talasemia, para cuadros con genotipos complejos, estudios prenatales o epidemiológicos.

Hemoglobinopathies are hereditary syndromes determined by a large variety of globin gene defects. Hemoglobinopathy diagnosis results from the combination of clinical orientation, laboratory tests and family studies. Basic tools include complete blood cell count, red blood cell count, hemoglobin quantification and red cell indices (MCV, MCH), blood film examination, reticulocyte count and iron status. Complementary determinations are hemoglobin electrophoresis, which enables the separation of the different hemoglobin variants according to their electrical charge, A2, and Fetal hemoglobin quantification, hemoglobin solubility and sickling test for Hb S diagnosis. Other techniques are based on physicochemical properties such as stability of hemoglobin for detection of unstable variants. In practice, the most useful tests are those that enable the detection of hemoglobinopathies, such as hemoglobin S, and the identification of the genetic defects is referred to specialized laboratories. The correct detection of the carriers of the different hemoglobinopathies is intended to give adequate genetic advice on the form of inheritance and the risk of having affected children with the severe forms of the disease and to avoid unnecessary treatments. Molecular diagnosis is reserved to a thalassemia complex genotypes, prenatal o epidemiological studies.

As hemoglobinopatias são distúrbios hereditários resultantes de uma grande variedade de defeitos que afetam os genes de globina. O diagnóstico das hemoglobinopatias decorre de uma combinação de estudos clínicos, provas de laboratório e estudo familiar. As ferramentas básicas incluem hemograma, hemoglobina e índices eritrocitários (VCM, HCM), morfologia dos eritrócitos, contagem de reticulócitos e perfil de ferro. As determinações complementares são eletroforese de hemoglobina que permite separar as diferentes variantes, de acordo com sua carga elétrica, quantificação de hemoglobina A2 (HbA2), Fetal (Hb F), provas de solubilidade hemoglobínica e falciformação. Outras técnicas baseiam-se em propriedades fisicoquímicas como a estabilidade da hemoglobina para detecção de variantes instáveis. Na prática, as provas mais úteis são as que permitem detectar a presença de hemoglobinopatias, como acontece com a hemoglobina S deixando para laboratórios especializados aqueles procedimentos para identificar a mutação. Detectar corretamente os portadores das diferentes hemoglobinopatías visa a dar um conselho genético adequado sobre a forma de herança, o risco de ter filhos afetados com as formas graves da doença e evitar tratamentos desnecessários. O diagnóstico molecular se reserva para a alfa talassemia, para quadros com genótipos complexos, estudos pré-natais ou epidemiológicos.

HbA1c levels in individuals heterozygous for hemoglobin variants / Dosagem de hemoglobina glicada em heterozigotos para hemoglobinas variantes

Summary Objective: To evaluate the levels of glycated hemoglobin (HbA1c) in patients heterozygous for hemoglobin variants and compare the results of this test with those of a control group. Method: This was an experimental study based on the comparison of HbA1c tests in two different populations, with a test group represented by individuals heterozygous for hemoglobin variants (AS and AC) and a control group consisting of people with electrophoretic profile AA. The two populations were required to meet the following inclusion criteria: Normal levels of fasting glucose, hemoglobin, urea and triglycerides, bilirubin > 20 mg/dL and non-use of acetylsalicylic acid. 50 heterozygous subjects and 50 controls were evaluated between August 2013 and May 2014. The comparison of HbA1c levels between heterozygous individuals and control subjects was performed based on standard deviation, mean and G-Test. Results: The study assessed a test group and a control group, both with 39 adults and 11 children. The mean among heterozygous adults for HbA1c was 5.0%, while the control group showed a rate of 5.74%. Heterozygous children presented mean HbA1c at 5.11%, while the controls were at 5.78%. G-Test yielded p=0.93 for children and p=0.89 for adults. Conclusion: Our study evaluated HbA1c using ion exchange chromatography resins, and the patients heterozygous for hemoglobin variants showed no significant difference from the control group.

Resumo Objetivo: Avaliar os níveis de hemoglobina glicada em pacientes heterozigotos para hemoglobinas variantes e comparar os resultados deste exame com grupo controle. Método: Trata-se de um estudo experimental, baseado na comparação do exame de hemoglobina glicada de duas populações diferentes, sendo um grupo teste, representado por indivíduos heterozigóticos para hemoglobinas variantes (AS e AC) e um grupo controle, constituído por pessoas com perfil eletroforético AA. As duas populações verificadas devem obedecer ao critério de inclusão: glicemia de jejum, hemoglobina, ureia e triglicérides normais, bilirrubina > 20 mg/dL e não fazer uso de ácido acetilsalicílico. Foram avaliados 50 indivíduos heterozigotos e 50 controles no período de agosto de 2013 a maio de 2014. A comparação dos valores de hemoglobina glicada entre indivíduos heterozigóticos e controle foi realizada por meio do desvio padrão, média e teste G. Resultados: O estudo analisou um grupo teste e um grupo controle, ambos com 39 adultos e 11 crianças. A média dos adultos heterozigotos para HbA1c foi de 5,0%, o grupo controle apresentou índice de 5,7%. Já as crianças heterozigóticas obtiveram média de HbA1c de 5,11%, enquanto as normais apresentaram valores médios de 5,78%. O valor do teste G foi de p=0,9 para crianças e p=0,89 para adultos. Conclusão: Este estudo avaliou HbA1c pela metodologia de cromatografia de coluna com resinas de troca iônica, em que pacientes com heterozigoses para hemoglobinas variantes não apresentaram uma diferença significativa em relação ao grupo controle.

A novel double heterozygote of HBB c.219T>A;220G>T: gene diagnosis and pedigree analysis / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To identify a novel hemoglobinopathy applied by direct sequencing and clone sequencing.</p><p><b>METHODS</b>EDTA anticoagulated blood of proband and his parents were analyzed by hematology analyzers and Capillarys hemoglobin electrophoresis (CE). Then thalassemia genetypes were screened by gap-PCR and reverse dot blot (RDB). Proband was suspected with abnormal hemoglobin combine alpha beta compound thalassemia. The mutation of beta-globin was identified by direct sequencing and clone sequencing.</p><p><b>RESULTS</b>Hb analysis showed that probands Hb A2 variant was eluted in Z (C) zone and his father's in Z (A2) zone on CE,and proband's mother elevated HbA2 of 4.6%. Screened by RDB, the proband was CD71-72(+A) homozygote and showed the mismatch with his parents. Through direct sequencing and clone sequencing, we deduced that our proband inherited the mutations of HBB c.[219T>A;220G>T] from his father and inherited the Southeast-Asian deletion and HBB c.216-217insA from his mother.</p><p><b>CONCLUSION</b>A novel double heterozygote of HBB c.[219T>A; 220G>T] was identified in south China. This mutation enriches the beta-thalassemia gene mutation spectrum in Chinese population.</p>

Analysis of clinical phenotype and genotype of unstable Hemoglobin Rush / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To analyze the hematological and genetic characteristics of unstable hemoglobin Rush (Hb Rush) and compound heterozygote of Hb Rush and thalassemia.</p><p><b>METHODS</b>Peripheral blood samples and genomic DNA from three patients (including two ethnic Dai and one Han Chinese) with anemia of undetermined origin were collected. Hematological phenotypes of these patients were determined through red blood cell analysis and hemoglobin electrophoresis. Genotypes of alpha- and beta-globin genes, -158 XmnⅠ polymorphic site ofγ promoter region, and haplotypes of 7 polymorphic restriction sites in the beta-globin gene cluster were determined using PCR-based methods and DNA sequencing.</p><p><b>RESULTS</b>All patients have presented hypochromic microcytic anemia and hemoglobin fraction with significant increased measurement (30.5%-59.2%) in the region of fetal hemoglobin during alkaline medium electrophoresis. DNA analysis suggested that all patients have carried mutations leading to the unstable hemoglobin Rush (HBB codon 101, GAG>CAG, Glu>Gln). Two of them were compound heterozygotes of Hb Rush and thalassemia mutations of -α,CD17 and Hb E, respectively. Hb Rush mutation was associated with various haplotypes of the β-globin gene cluster. No significant association was found between increased abnormal hemoglobin fraction in the region of Hb F and the polymorphism ofγ promoter or large deletion of the beta-globin gene cluster.</p><p><b>CONCLUSION</b>This study has confirmed the distribution of Hb Rush among various Chinese populations and is the third report of its kind. Hb Rush can result in increased measurement of hemoglobin fraction in the region of fetal hemoglobin (Hb F) during routine hemoglobin electrophoresis under alkaline condition. Hb Rush heterozygote alone can lead to hypochromic microcytic anemia and thalassemia-like phenotype. Prenatal diagnosis of Hb Rush is necessary for carriers.</p>

Management and Outcomes of Fetal Hydrops in a Tertiary Care Centre in Singapore

: Fetal hydrops is a serious condition which can be caused by immune and non-immune aetiologies. We aimed to review the management of fetal hydrops at our hospital.: A retrospective review of all cases of fetal hydrops diagnosed in our institution from 2006 to 2013 was carried out.: Out of the 30 cases of fetal hydrops diagnosed antenatally, 17 were cases of Bart's hydrops which were all terminated in-utero. Of the remaining 13 cases, 11 cases consisted of non-immune causes of hydrops. Planned antenatal interventions including in-utero blood transfusions (n = 4) and thoracentesis (n = 5) as well as planned caesarean deliveries (n = 11) were performed in the majority of cases. Postnatal neonatal intensive care with interventions including chest drainage and transfusions were also performed. A majority, 92%, of the cases survived the perinatal period following a variable length of hospital stay ranging from a week to 3 months.: Management of fetal hydrops is complex. Close coordination between the obstetric and neonatal teams was the key to good short-term survival of neonates with antenatally diagnosed hydrops, as it allows timely antenatal intervention and anticipation of potential perinatal complications.

Analysis of the phenotype-genotype relationship of hemoglobin Q-Thailand in Guangxi / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the hematological and molecular characteristics of hemoglobin Q-Thailand in Guangxi, so as to provide reference data for hemoglobinopathy screening.</p><p><b>METHODS</b>A total of 51088 samples were screened by capillary electrophoresis. Samples suspected with Hb Q-Thailand were processed with blood cell count and DNA sequencing. Gap-PCR and PCR-reverse dot blotting were used for the detection of common mutations of alpha and beta thalassemia.</p><p><b>RESULTS</b>The carrier rate of Hb Q-Thailand in Guangxi was 0.06%. The hematological phenotype index(HGB, MCV, MCH, Hb Q-Thailand, Hb A2, Hb QA2) of 28 Hb Q-Thailand heterozygous samples were (125.60±22.30) g/L, (78.22±4.81) fl, (25.79±2.14) pg, (27.37±2.72)%, (1.89±0.22)%, (0.69±0.16)%, respectively, and of 2 Hb Q-Thailand heterozygous combined with beta-thalassemia samples were (125.00±18.39) g/L, (69.65±5.02) fl, (22.00±0.0) pg, (14.80±0.71)%, (4.45±0.07)%, (0.95±0.71)%, respectively. A statistical difference was found in hematological phenotype index between the two groups except HGB (P<0.05).</p><p><b>CONCLUSION</b>In Guangxi, the detected Hb Q-Thailands were mainly heterozygous. Part of Hb Q-Thailand heterozygotes had normal red blood cell parameters, but can still be detected by hemoglobin electrophoresis. When combined with other types of thalassemia, these heterozygotes may still exhibit reduced MCV and MCH or various degrees of anemia.</p>