Anemia, Hemolytic, Congenital ; etiology ; genetics ; Asian Continental Ancestry Group ; Humans ; Infant, Newborn ; Male ; Mutation ; genetics ; Pyruvate Kinase ; genetics

Anemia, Hemolytic, Congenital ; Humans ; Ion Channels/genetics* ; Mutation

Anemia, Hemolytic, Congenital Nonspherocytic ; Erythrocytes ; Humans ; Pyruvate Kinase/deficiency* ; Pyruvate Metabolism, Inborn Errors

Primary distal renal tubular acidosis (dRTA) caused by mutations of the SLC4A1 gene, which encodes for erythroid and kidney isoforms of anion exchanger, shows marked difference in inheritance patterns and clinical features in different parts of the world. While the disease shows autosomal dominant inheritance without any red cell morphological abnormalities in the temperate countries, it is almost invariably recessive, and often accompanies red cell morphological abnormalities or hemolytic anemia in the tropics, especially in Southeast Asia. Here, we report three patients with autosomal recessive (AR) dRTA, presenting with typical findings of failure to thrive and rickets, from two unrelated Lao families. The mutational analyses revealed that all three patients harbored the same homozygous SLC4A1 mutation, p.Gly701Asp. Adequate supplementation of alkali and potassium resulted in remarkable improvement of growth retardation and skeletal deformities of the patients. This is the first case report of Lao patients with AR dRTA caused by SLC4A1 mutations.
Acidosis, Renal Tubular* ; Alkalies ; Anemia, Hemolytic ; Asia, Southeastern ; Congenital Abnormalities ; Failure to Thrive ; Humans ; Inheritance Patterns ; Kidney ; Laos ; Potassium ; Protein Isoforms ; Rickets ; Wills

OBJECTIVETo evaluate the feasibility of genetic and prenatal diagnosis for a family affected with pyruvate kinase deficiency (PKD).

METHODSTargeted sequence capture and high-throughput sequencing technology was used to detect the exons and exon-intron boundaries of the PKLR gene in a clinically suspected PKD patient. Meanwhile, the genotype of the pedigree was validated by Sanger sequencing. Prenatal genetic diagnosis was performed by amniotic fluid sampling after genotype of the mother of the proband was determined.

RESULTSThe proband was found to harbor double heterozygous mutations, c.661G>A (Asp221Asn) and c.1528C>T (Arg510Ter), which resulted in amino acid substitution Asp221Asn and Arg510Ter. Such mutations were confirmed by Sanger sequencing. The mother and father of the proband were detected to have respectively carried c.1528C>T (Arg510Ter) and c.661G>A (Asp221Asn) mutation. The fetus was found to have carried the same mutations as the proband. Following selected abortion, analysis of fetal tissue was consistent with the result of prenatal diagnosis.

CONCLUSIONThe compound mutations of c.661G>A and c.1528C>T of PKLR gene probably underlie the PKD in the family. Prenatal diagnosis of the mutations analysis can facilitate detection of affected fetus in time.

Adult ; Anemia, Hemolytic, Congenital Nonspherocytic ; embryology ; enzymology ; genetics ; Base Sequence ; Child, Preschool ; DNA Mutational Analysis ; Exons ; Female ; Genotype ; Humans ; Male ; Molecular Sequence Data ; Mutation ; Pedigree ; Pregnancy ; Prenatal Diagnosis ; Pyruvate Kinase ; deficiency ; genetics ; metabolism ; Pyruvate Metabolism, Inborn Errors ; embryology ; enzymology ; genetics

Hereditary hemolytic anemia is a very heterogeneous disorder in which abnormalities of red blood cell structural protein, globin protein, or enzyme defect lead to shortened life span. There has been much progress in revealing its pathophysiology and genetic backgrounds, but the lifelong plans for caring these patients are not well established yet. All patients with hereditary hemolytic anemic have three common problems: transfusion dependency, iron overload and iron chelation therapy. Patients with hereditary spherocytosis (HS) usually manifest severe anemia in neonatal period and infancy, but transfusion requirements may decrease in adulthood. But patients with thalassemia or sickle cell disease usually transfusion-dependent throughout life. Maintaining the optimal hemoglobin (Hb) levels in these patients is crucial because correction of anemia and dilution of abnormal Hb helps prevent certain complications that frequently occur in these patients. Frequent transfusion leads to transfusion-mediated infection and hemochromatosis. Iron chelation therapy should be started early to prevent permanent organ damage. Folate therapy can be helpful in patients with hereditary spherocytosis. Regular evaluations for cholestasis should be started at age 5, and splenectomy with concurrent cholecystectomy can be considered if the patient has cholecystitis. Hydroxyurea can be used to reduce transfusion requirements and prevent complications in patients with β-thalassemia and sickle cell disease. Consensus on long-term management of patients with hereditary hemolytic anemia is lacking, especially for adult patients. But further efforts to build guidelines for long-term follow-up and management of the patients with hereditary hemolytic anemia in the context of Korean society are needed.
Adult ; Anemia ; Anemia, Hemolytic, Congenital ; Anemia, Sickle Cell ; Chelation Therapy ; Cholecystectomy ; Cholecystitis ; Cholestasis ; Consensus ; Erythrocytes ; Folic Acid ; Follow-Up Studies ; Globins ; Hemochromatosis ; Humans ; Hydroxyurea ; Iron ; Iron Overload ; Splenectomy ; Thalassemia

OBJECTIVETo explore the molecular mechanism of erythrocyte pyruvate kinase deficiency (PKD).

METHODSTargeted sequence capture and next-generation sequencing (NGS) were used to detect the regions of exon and exon-intron boundarie of PKLR gene in a clinical suspected PKD patient. The protein function of mutant gene was forecasted by the SIFT and PolyPhen-2 databank, after the mutation of PKLR gene in the patient was detected by the NGS technology, its genotype was confirmed by Sanger sequencing.

RESULTSThe patient was found to have peculiar double heterozygous mutations: 661 G>A (Asp221Asn) of exon 5 and 1528 C>T (Arg510Ter) of exon 10, resulting in amino acid substitution Asp221Asn and Arg510Ter, these mutations were also further confirmed by Sanger sequencing. The complex mutations were infrequent and each of them was able to cause diseases.

CONCLUSIONThe complex mutations of both 661 G>A and 1528 C>T of PKLR gene are the molecular mechanism of PKD. Simultaneous existance of above-mentioned complex mutations in PDK patient was never been previously reported at home and abroad.

Anemia, Hemolytic, Congenital Nonspherocytic ; genetics ; Exons ; Genotype ; High-Throughput Nucleotide Sequencing ; Humans ; Introns ; Mutation ; Pyruvate Kinase ; deficiency ; genetics ; Pyruvate Metabolism, Inborn Errors ; genetics

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common enzyme disorder. There are more than 400 million people worldwide with G6PD deficiency, and its distribution is similar to that of malaria. G6PD deficiency is an X-linked recessive disorder. Most patients with G6PD deficiency may be asymptomatic throughout their lives. They may present as neonatal jaundice, or acute and chronic hemolysis. The most important point in the management of G6PD deficiency is to avoid oxidative stress. The prevalence of G6PD deficiency in Korea is about 0.9%. However, a nationwide survey has revealed that the number of patients with enzymopathy is increasing. Immigration of different ethnicities into Korea, and the rise of interracial marriages will likely lead to an increase in the number of patients with G6PD deficiency.
Anemia, Hemolytic, Congenital ; Anemia, Hemolytic, Congenital Nonspherocytic ; Emigration and Immigration ; Favism ; Glucosephosphate Dehydrogenase ; Glucosephosphate Dehydrogenase Deficiency ; Hemolysis ; Humans ; Infant, Newborn ; Jaundice, Neonatal ; Korea ; Malaria ; Marriage ; Oxidative Stress ; Prevalence ; Splenectomy

OBJECTIVETo screen potential mutation and explore the underlying mechanism for a consanguineous pedigree featuring pyruvate kinase (PK) deficiency.

METHODSThe red blood cell pyruvate kinase activities of all family members were detected. All the exons and intron-exon boundaries of the PKLR gene for the proband were amplified and analyzed by direct sequencing. Restriction endonuclease enzymes were used to identify the presence of mutations of all family members.

RESULTSThe pyruvate kinase activities were 5.89 U/g Hb in the proband, 3.45, 6.54, 8.87, 7.89, 9.32 U/g Hb in his younger sister, father, mother, grandmother and elder aunt, respectively. The homozygous missense mutation of T>C transition at position 941 in exon 7 of PKLR gene resulted to a Ile314Thr substitution in the proband, and mutant alleles were identified at the level of RNA transcript by cDNA sequence analysis. His younger sister was also homozygous for Ile314Thr. Heterozygosity for Ile314Thr was confirmed in his grandmother, parents and elder aunt.

CONCLUSIONIle314Thr homozygous missense mutation in exon 7 of PKLR is the molecular mechanism of pyruvate kinase deficiency in this family.

Anemia, Hemolytic, Congenital Nonspherocytic ; genetics ; Child, Preschool ; Female ; Humans ; Male ; Pedigree ; Point Mutation ; Pyruvate Kinase ; deficiency ; genetics ; Pyruvate Metabolism, Inborn Errors ; genetics

BACKGROUND: The number of patients diagnosed with hereditary hemolytic anemia (HHA) has increased since the advent of novel diagnostic techniques that accurately identify this disorder. Here, we report data from a survey on the prevalence and characteristics of patients diagnosed with HHA in Korea from 2007 to 2011. METHODS: Information on patients diagnosed with HHA in Korea and their clinical and laboratory results were collected using a survey questionnaire. Globin gene and red blood cell (RBC) enzyme analyses were performed. In addition, we analyzed data collected by pediatricians. RESULTS: In total, 195 cases of HHA were identified. Etiologies identified for HHA were RBC membranopathies, hemoglobinopathies, and RBC enzymopathies, which accounted for 127 (64%), 39 (19.9%), and 26 (13.3%) cases, respectively. Of the 39 patients with hemoglobinopathies, 26 were confirmed by globin gene analysis, including 20 patients with beta-thalassemia minor, 5 patients with alpha-thalassemia minor, and 1 patient with unstable hemoglobin disease. CONCLUSION: The number of patients diagnosed with hemoglobinopathies and RBC enzymopathies has increased considerably since the previous survey on HHA in Korea, dated from 1997 to 2006. This is likely the result of improved diagnostic techniques. Nevertheless, there is still a need for more sensitive diagnostic tests utilizing flow cytometry and for better standardization of test results to improve the accuracy of diagnosis of RBC membranopathies in Korea. Additionally, more accurate assays for the identification of RBC enzymopathies are warranted.
alpha-Thalassemia ; Anemia, Hemolytic, Congenital ; beta-Thalassemia ; Diagnostic Tests, Routine ; Erythrocytes ; Flow Cytometry ; Globins ; Hematology ; Hemoglobinopathies ; Hemoglobins ; Humans ; Korea ; Prevalence ; Spherocytosis, Hereditary ; Thalassemia ; Surveys and Questionnaires