Inherited hemolytic anemias (IHAs) are genetic diseases that present with anemia due to the increased destruction of circulating abnormal RBCs. The RBC abnormalities are classified into the three major disorders of membranopathies, hemoglobinopathies, and enzymopathies. Traditional diagnosis of IHA has been performed via a step-wise process combining clinical and laboratory findings. Nowadays, the etiology of IHA accounts for germline mutations of the responsible genes coding for the structural components of RBCs. Recent advances in molecular technologies, including next-generation sequencing, inspire us to apply these technologies as a first-line approach for the identification of potential mutations and to determine the novel causative genes in patients with IHAs. We herein review the concept and strategy for the genetic diagnosis of IHAs and provide an overview of the preparations for clinical applications of the new molecular technologies.
Anemia ; Anemia, Hemolytic* ; Clinical Coding ; Diagnosis ; Genetic Testing ; Germ-Line Mutation ; Hemoglobinopathies ; Humans

The hereditary hemolytic anemia (HHA) can be classified into three types according to the pathogenesis: RBC membrane defects, hemoglobinopathies, and RBC enzymopathies. Clinical characteristics of these three types of HHA are presented briefly in this paper. In Korea, HHA due to RBC membrane defect such as hereditary spherocytosis had been relatively well recognized, while HHA due to hemoglobinopathies and RBC enzymopathies had been considered rare. However, with the recent development of molecular testing, beta thalassemia, G6PD and pyruvate kinase deficiency have been reported with identification of disease-causing mutations. If a patient with microcytic hypochromic anemia shows unproportionally low MCV or MCH or refractory to iron therapy, hemoglobin electrophoresis and gene study for thalassemia or other unstable hemoglobinopathies are needed. It should be noted that the recent population migration to Korea from the regions where hemoglobinopathies or enzymopathies are prevalent warrants considering a broad spectrum of etiologies for the diagnosis of HHA.
Anemia, Hemolytic, Congenital* ; Anemia, Hypochromic ; beta-Thalassemia ; Diagnosis ; Electrophoresis ; Hemoglobinopathies ; Humans ; Iron ; Korea ; Membranes ; Pyruvate Kinase ; Thalassemia

The author obtained index of red cell volume distribution width(RDW) and other red cell indices in 210 patients of various hematoncologic conditions and 200 healthy control group using, an automated blood analyzer, Coulter Counter Model S-plus II. This study performed to classify various etiologic anemia based on the MCV and RDW, to evaluate availability to the differential diagnosis in korean anemic distoders somewhat different from etiologies of anemias in foreginers. In the most of cases, the increase or decrease of MCV were always combined the pararell changes of MCH and MCHC: But the values of MCV and RDW were not correlated in control group and patient group. So the terms of heterogenous of homogenous anemia were meaningful morphologic classification than hypochromic or normochromic anemia. The heterogenous microcytic anemia contained iron deficiency anemia. In heterogenous normocytic anemia, myelophthisic anemia, acute leukemia were contained. In heterogenous macrocytic anemia, megaloblastic anemia, hemolytic anemia were contained. The homogenous microcytic anemia was observed in anemia of chronic disorders. In homogenous normocytic anemia, acute blood loss, chronic leukemia, multiple myeloma were contained. The aplastic anemia was belonged to homogenous macrocytic anemia. The diagnostic significance of RDW in hemoglobinopathies is most importhant. But this study was not contained hemoglobinopathies. Instead RDW was very helpful to differential diagnosis of most common anemias, iron deficiency anemia and anemia due to chronic disorders in Korea.
Anemia* ; Anemia, Aplastic ; Anemia, Hemolytic ; Anemia, Iron-Deficiency ; Anemia, Macrocytic ; Anemia, Megaloblastic ; Anemia, Myelophthisic ; Cell Size ; Classification* ; Diagnosis, Differential ; Erythrocyte Indices ; Hemoglobinopathies ; Humans ; Korea ; Leukemia ; Multiple Myeloma

To understand the hemolytic anemia (HA) in children, the diagnostic approach and management of hereditary and acquired HA are described. The hereditary hemolytic anemia (HHA) can be classified according to the pathogenesis into three types:RBC membrane defects, hemoglobinopathies, and RBC enzymopathies. Clinical characteristics, laboratory findings and molecular defects of these three types are presented briefly. In Korea, HHA due to the RBC membrane defect, hereditary spherocytosis had been reported often but HHA due to hemoglobinopathies and RBC enzymopathies had been thought to be relatively rare. With recent development in the molecular diagnosis, beta thalassemia, mostly heterozygote, G6PD and pyruvate kinase deficiency have been reported with gene characterization. If the patients with microcytic hypochromic anemia show unproportionally low MCV or MCH or refractory to the iron therapy, hemoglobin electrophoresis and gene analysis for thalassemia or other unstable hemoglobinopathies need to be done accordingly. The global movement of the population especially from the region prevalent of hemoglobinopathies or enzymopathies to Korea warrants considering broad spectrum of etiology for the diagnosis of HHA. Aquired HA resulting from extracellular factors such as autoimmune HA from warm antibody, cold agglutinin and paroxysmal cold hemoglobinuria as well as nonimmune HA are described briefly.
Anemia, Hemolytic* ; Anemia, Hemolytic, Autoimmune ; Anemia, Hemolytic, Congenital ; Anemia, Hypochromic ; beta-Thalassemia ; Child ; Diagnosis ; Electrophoresis ; Hemoglobinopathies ; Hemoglobinuria, Paroxysmal ; Heterozygote ; Humans ; Iron ; Korea ; Membranes ; Pediatrics* ; Pyruvate Kinase ; Thalassemia

BACKGROUND: Hemoglobinopathy is inherited anemia characterized by abnormal structure of one of the globin chains of the hemoglobin molecule and has been known to be rare in Korea. However, hemoglobinopathy in children has been reported more frequently than in past with the recent advancement of molecular testing. The purpose of this study was to investigate the clinical and laboratory findings, prevalence and complications of hemoglobinopathy of children.METHODS: Data of pediatric patients diagnosed with hemoglobinopathy from 2002 to February 2014 at Ajou University Hospital were surveyed. We analyzed patients' characteristics from clinical and laboratory findings retrospectively.RESULTS: Among a total of 10 children who were diagnosed with hemoglobinopathy, 9 patients were confirmed hemoglobinopathy by gene analysis. Eight patients had beta thalassemia, 1 hemoglobin D disease, and 1 hemoglobin Koriyama. In most of the children, anemia was found incidentally and most of the children did not have symptoms. In the initial blood test, their mean hemoglobin concentration was 10.0 g/dL (range: 4.7-11.2 g/dL), mean corrected reticulocyte count was 3.9% (range: 0.9%-12.2%), and mean total bilirubin level was 1.0 mg/dL (range: 0.3-5.8 mg/dL).CONCLUSION: The analysis of clinical and laboratory features showed that the characteristics of each type of hemoglobinopathy were similar to that previously reported. We recommend considering hemoglobinopathy if pediatric patient presents with hemolytic anemia. A well organized diagnostic approach including molecular genetic analysis is needed for accurate diagnoses and appropriate management of hemoglobinopathy.
Anemia ; Anemia, Hemolytic ; beta-Thalassemia ; Bilirubin ; Child ; Diagnosis ; Globins ; Hematologic Tests ; Hemoglobinopathies ; Humans ; Korea ; Molecular Biology ; Prevalence ; Reticulocyte Count ; Retrospective Studies

Genetic hemoglobin disorders are caused by mutations and/or deletions in the α-globin or β-globin genes. Thalassemia is caused by quantitative defects and hemoglobinopathies by structural defect of hemoglobin. The incidence of thalassemia and hemoglobinopathy is increased in Korea with rapid influx of people from endemic areas. Thus, the awareness of the disease is needed. α-thalassemias are caused by deletions in α-globin gene, while β-thalassemias are associated with decreased synthesis of β-globin due to β-globin gene mutations. Hemoglobinopathies involve structural defects in hemoglobin due to altered amino acid sequence in the α- or β-globin chains. When the patient is suspected with thalassemia/hemoglobinopathy from abnormal complete blood count findings and/or family history, the next step is detecting hemoglobin abnormality using electrophoresis methods including high performance liquid chromatography and mass spectrometry. The development of novel molecular genetic technologies, such as massively parallel sequencing, facilitates a more precise molecular diagnosis of thalassemia/hemoglobinopathy. Moreover, prenatal diagnosis using genetic testing enables the prevention of thalassemia birth and pregnancy complications. We aimed to review the spectrum and classification of thalassemia/hemoglobinopathy diseases and the diagnostic strategies including screening tests, molecular genetic tests, and prenatal diagnosis.
Amino Acid Sequence ; Anemia ; Blood Cell Count ; Chromatography, Liquid ; Classification ; Clinical Laboratory Techniques ; Diagnosis ; Electrophoresis ; Erythrocytes ; Genetic Testing ; Hematology ; Hemoglobinopathies ; High-Throughput Nucleotide Sequencing ; Humans ; Incidence ; Korea ; Mass Screening ; Mass Spectrometry ; Molecular Biology ; Parturition ; Pregnancy Complications ; Prenatal Diagnosis ; Thalassemia

BACKGROUND: beta-thalassemia is primarily found in individuals of Mediterranean and Southeast Asian ancestry. With rapid growth in the Southeast Asian segments of the Korean population, the geographic distribution of hemoglobinopathies is expected to become significantly different from what it is today. In this study, Hb fractions were measured in patients with hypochromic microcytosis to detect thalassemia and Hb variants. To evaluate the feasibility of replacing cellulose acetate electrophoresis (CA) with capillary electrophoresis (CE) in a clinical laboratory, both techniques were performed and the outcomes were compared. METHODS: To evaluate hemoglobinopathies, complete blood cell counts (CBC), CA, and CE were carried out on samples from healthy and microcytic hypochromic groups. The microcytic hypochromic group consisted of 103 patients whose mean corpuscular volume (MCV) was less than 75 fL and mean corpuscular hemoglobin (MCH) was less than 24 pg. Quantitative analysis of Hb fractions was performed on 143 whole blood samples. RESULTS: There was a good correlation for measurements of HbA (r=0.9370, P<0.0001), HbA2 (r=0.8973 P<0.0001), and HbF (r= 0.8010, P=0.0304) between the two methods. In the microcytic hypochromic group, there were 29 cases (28.2%) with decreased HbA2, 2 cases (1.9%) with increased HbA2, 3 cases (2.9%) with increased HbF, and 2 cases (1.9%) with increased HbA2 and HbF. CONCLUSIONS: CE is comparable to CA for reliable measurement of Hb fractions. It is suitable for screening of hemoglobinopathies in many clinical laboratories.
Adult ; Aged ; Aged, 80 and over ; Blood Cell Count ; *Electrophoresis, Capillary ; *Electrophoresis, Cellulose Acetate ; Erythrocyte Indices ; Female ; Fetal Hemoglobin/analysis ; Hemoglobin A/analysis ; Hemoglobin A2/analysis ; Hemoglobinopathies/*diagnosis ; Humans ; Male ; Middle Aged

BACKGROUND: The aim of this study was to investigate the prevalence, clinical and laboratory findings of hereditary hemolytic anemia (HHA) in Korea from 1997 to 2006 and to develop the appropriate diagnostic approach for HHA. METHODS: By the use of questionnaires, information on the clinical and laboratory findings ofHHA diagnosed from 1997 to 2006 in Korea was collected and analyzed retrospectively. A total of 431 cases were enrolled in this study from 46 departments of 35 hospitals. RESULTS: The overall frequency of HHA did not change through the 10-year period for pediatrics but did show an increasing tendency for internal medicine. The overall male to female sex ratio did not show sex predominance (1.17:1), but a significant male predominance with a ratio of 1.49:1 was seen for pediatrics while a significant female predominance with a ratio of 1:1.97 was seen forinternal medicine. Of the total cases, 74.2% (282/431) were diagnosed before the age of 15 years. The etiologies of HHA were classified as red cell membrane defects, hemoglobinopathies, red cell enzyme deficiencies and unknown causes. There were 382 cases (88.6%) of red cell membrane defects with 376 cases (87.2%) of hereditary spherocytosis and 6 cases (1.4%) of hereditary elliptocytosis, 20 cases (4.6%) of hemoglobinopathies with 18 cases (4.2%) of beta-thalassemia, a case (0.2%) of alpha-thalassemia and a case (0.2%) of Hemoglobin Madrid, 7 cases (1.6%) of red cell enzyme deficiencies with 5 cases (1.2%) of glucose-6- phosphate dehydrogenase (G-6-PD) deficiency, a case (0.2%) of pyruvate kinase (PK) deficiency and a case (0.2%) of enolase deficiency, and 22 cases (5.1%) of unknown causes. The most common chief complaint in pediatric patients was pallor and that in adult patients was jaundice. In the red cell membrane defect group of patients, the level of hemoglobin was significantly higher than in adult patients. The mean corpuscular volume, mean corpuscular hemoglobin, corrected reticulocyte count, total and indirect bilirubin level and lactate dehydrogenase levels in the hemoglobinopathy group of patients were significantly lower than the values in the red cell membrane defect group of patients. The mean concentration of G-6-PD was 0.8+/-0.7U/1012RBC in the G-6-PD deficient patients, PK was 1.7U/1010 RBC in the PK deficient patient, and the level of enolase was 0.04U/g of Hb in the enolase deficient patient. CONCLUSION: The most prevalent cause of HHA in Korea during 1997 to 2006 was hereditary spherocytosis, but HHA by other causes such as hemoglobinopathy and red cell enzyme deficiency gradually increased with the development of molecular diagnostic methods and increasing general interest. However, the etiologies of HHA need to be pursued further in 5.1% of the patients. An systematic standard diagnostic approach is needed in a nationwide prospective study for correct diagnoses and appropriate management of HHA.
Adult ; alpha-Thalassemia ; Anemia, Hemolytic, Congenital* ; beta-Thalassemia ; Bilirubin ; Cell Membrane ; Diagnosis ; Elliptocytosis, Hereditary ; Erythrocyte Indices ; Female ; Hemoglobinopathies ; Humans ; Internal Medicine ; Jaundice ; Korea* ; L-Lactate Dehydrogenase ; Male ; Oxidoreductases ; Pallor ; Pathology, Molecular ; Pediatrics ; Phosphopyruvate Hydratase ; Prevalence ; Pyruvate Kinase ; Reticulocyte Count ; Retrospective Studies* ; Sex Ratio ; Surveys and Questionnaires