Molecular characteristics of hereditary red blood cell membrane disorders in Thailand: a multi-center registry.

Red blood cell (RBC) membrane disorders represent a significant category of hereditary hemolytic anemia; however, information from Southeast Asia is limited. We established a national registry aiming to characterize RBC membrane disorders and their molecular features in Thailand. A total of 100 patients (99 kindreds) diagnosed with RBC membrane disorders between 2011 and 2020 from seven university hospitals were enrolled. The most prevalent disorders observed were hereditary elliptocytosis (HE; n=33), hereditary pyropoikilocytosis (HPP; n=28), hereditary spherocytosis (HS; n=19), Southeast Asian ovalocytosis (SAO; n=10 of 9 kindreds), and two cases of homozygous SAO. The remaining cases were grouped as unclassified membrane disorder. Seventy-six patients (76%) were molecularly confirmed by PCR, direct DNA sequencing, or hi-throughput sequencing. The primary causative gene for HE and HPP was SPTB, accounting for 28 out of 29 studied alleles for HE and 56 of 56 studied alleles for HPP. In the case of HS, dominant sporadic mutations in the ANK1 gene (n=4) and SPTB gene (n=3) were identified as the underlying cause. Notably, the four most common variants causing HE and HPP were SPTB Providence (c.6055 T>C), SPTB Buffalo (c.6074 T>G), SPTB Chiang Mai (c.6224 A>G), and SPTB c.6171__82delins TGCCCAGCT. These recurrent SPTB mutations accounted for 79 out of 84 mutated SPTB alleles (94%). In summary, HE and hereditary HPP associated with recurrent SPTB mutations are the predominant types of RBC membrane disorders observed in Thailand. These findings have significant implications for the clinical management and future research of RBC membrane disorders in the region.

Growth Failure in Hereditary Spherocytosis and the Effect of Splenectomy.

OBJECTIVE: To analyze growth-failure and improvement, if any, following splenectomy in children with hereditary spherocytosis. METHODS: Data collection from case-records (n=82) over 27-years (1985-2011). RESULTS: Prevalence of stunting was 26%; 32% were underweight. Stunted children were older in age (P=0.006) and presented late (P=0.003). Splenectomy (n=26) improved anemia (P<0.001). However, height-for-age did not improve at 1-year, or 4.5-years (median) following splenectomy (P=1.0). Number of underweight children did not reduce at 1- (P=0.21), or 4.5-years (P=0.21) following surgery. CONCLUSION: Growth-failure is frequent in children with hereditary spherocytosis in India. Splenectomy corrected the anemia but failed to improve the growth.

[Hereditary spherocytosis: Review. Part I. History, demographics, pathogenesis, and diagnosis]. / Esferocitosis hereditaria: Revisión. Parte I. Historia, demografía, etiopatogenia y diagnóstico.

Hereditary spherocytosis is the most frequent hereditary anemia excluding beta thalassemia in Argentina. Historical, demographic, genetic and pathogenic aspects of the disease are reviewed, and confirmatory laboratory tests are described. Special characteristics on the outcome of the disease in our population and prevalent protein deficiencies in our country are described. Emphasis is given on new available laboratory tests, which allow an earlier diagnosis using volume of blood samples significantly smaller than required for conventional tests.

Esferocitosis hereditaria: Revisión. Parte I. Historia, demografía, etiopatogenia y diagnóstico / Hereditary spherocytosis. Review. Part I. History, demographics, pathogenesis, and diagnosis

La esferocitosis hereditaria es la anemia hereditaria más frecuente en nuestro país luego de la talasemia menor. En este artículo, se revisan aspectos históricos, demográficos, genéticos y etiopatogénicos de la enfermedad, y se describen las pruebas de laboratorio para su diagnóstico. Se remarca el comportamiento de la enfermedad en nuestra población y se detallan las deficiencias proteicas predominantes en nuestro país. Se enfatiza sobre las nuevas técnicas de laboratorio actualmente disponibles, con alta sensibilidad y especificidad, que permiten realizar un diagnóstico más temprano con volúmenes de muestra mucho menores que los necesarios para las pruebas convencionales.

Hereditary spherocytosis is the most frequent hereditary anemia excluding beta thalassemia in Argentina. Historical, demographic, genetic and pathogenic aspects of the disease are reviewed, and confirmatory laboratory tests are described. Special characteristics on the outcome of the disease in our population and prevalent protein deficiencies in our country are described. Emphasis is given on new available laboratory tests, which allow an earlier diagnosis using volume of blood samples significantly smaller than required for conventional tests.

Is activity restriction appropriate for patients with hereditary spherocytosis? A population-based analysis.

Patients with hereditary spherocytosis (HS) are often thought to have an increased risk of blunt splenic injury (BSI) from trauma due to splenomegaly. We aim to quantify this risk. Using a population-based database consisting of all injury-related admissions in Canada from 2001 to 2010, we identified patients with BSI and HS based on the discharge diagnoses. Intercensal population estimates were used to derive rates of BSI. The HS population at risk for BSI was estimated based on population rates of HS obtained from the literature. Rates of BSI in the HS population were estimated and the relative rates of BSI were calculated to compare the populations with and without HS. There were 10,106 patients with BSI over 202,405,788 person-years of observation, yielding an overall rate of BSI in the general population of 5.0 BSI per 100,000 person-years. Of these BSI patients, only two had a history of HS. Population rates of HS in the literature range from 1 in 2,000 to 5,000, corresponding to a low estimate of 2.0 and a high estimate of 4.9 BSI per 100,000 person-years in the HS population. The relative rate of BSI in the population with HS compared to the population without HS ranged from a low of 0.4 (95 % CI 0.1-1.4) to a high of 1.0 (0.1-3.6). The rate of BSI in the HS patient population appears not to differ significantly from those in the general population.

Esferocitosis hereditaria: de la biogénesis a la patogénesis / Hereditary spherocytosis: from biogenesis to pathogenesis

La esferocitosis hereditaria es la anemia hemolítica congénita más frecuente en la población caucásica. Tiene una amplia variabilidad clínica y desde el punto de vista hematológico se caracteriza por anemia y presencia de esferocitos en la lámina periférica. Su base fisiopatológica está determinada por el defecto de algunas de las proteínas que conforman la membrana eritrocitaria, por el efecto del bazo sobre los hematíes anómalos y otros factores. A la luz de los conocimientos actuales, la interpretación dinámica del proceso requiere adentrarse en los estadios iniciales de la hematopoyesis, pues desde etapas tan tempranas como la enucleación del eritroblasto en la formación del reticulocito, hasta posibles procesos inflamatorios tardíos, pudieran modular la expresión de la enfermedad. Se hace una revisión de las características estructurales y funcionales de la membrana eritrocitaria, así como algunos aspectos generales de las propiedades del hematíe para facilitar la comprensión de los eventos que tienen lugar a partir del compromiso molecular de las proteínas que conforman la membrana(AU)

Hereditary spherocytosis is the most common congenital hemolytic anemia among Caucasian population. It has wide clinical variety and from the haematological point of view, it is characterized by the presence of spherocytes anemia in peripheral lamina. Its pathophysiological defect is determined by some of the proteins that make up the red cell membrane due to the effect on erythrocytes of abnormal spleen, and other factors. In view of current knowledge, the dynamic interpretation of this process requires delving into the early stages of hematopoiesis, since the expression of this disease could modulate from early stages of erythroblast enucleation in reticulocyte formation until late potential inflammatory processes. A review was made on the structural and functional characteristics of the erythrocyte membrane, as well as some general aspects of the properties of the red cell to facilitate understanding of events which take place through proteins molecular involvement forming the membrane(AU)

Esferocitosis hereditaria: de la biogénesis a la patogénesis / Hereditary spherocytosis: from biogenesis to pathogenesis

La esferocitosis hereditaria es la anemia hemolítica congénita más frecuente en la población caucásica. Tiene una amplia variabilidad clínica y desde el punto de vista hematológico se caracteriza por anemia y presencia de esferocitos en la lámina periférica. Su base fisiopatológica está determinada por el defecto de algunas de las proteínas que conforman la membrana eritrocitaria, por el efecto del bazo sobre los hematíes anómalos y otros factores. A la luz de los conocimientos actuales, la interpretación dinámica del proceso requiere adentrarse en los estadios iniciales de la hematopoyesis, pues desde etapas tan tempranas como la enucleación del eritroblasto en la formación del reticulocito, hasta posibles procesos inflamatorios tardíos, pudieran modular la expresión de la enfermedad. Se hace una revisión de las características estructurales y funcionales de la membrana eritrocitaria, así como algunos aspectos generales de las propiedades del hematíe para facilitar la comprensión de los eventos que tienen lugar a partir del compromiso molecular de las proteínas que conforman la membrana

Hereditary spherocytosis is the most common congenital hemolytic anemia among Caucasian population. It has wide clinical variety and from the haematological point of view, it is characterized by the presence of spherocytes anemia in peripheral lamina. Its pathophysiological defect is determined by some of the proteins that make up the red cell membrane due to the effect on erythrocytes of abnormal spleen, and other factors. In view of current knowledge, the dynamic interpretation of this process requires delving into the early stages of hematopoiesis, since the expression of this disease could modulate from early stages of erythroblast enucleation in reticulocyte formation until late potential inflammatory processes. A review was made on the structural and functional characteristics of the erythrocyte membrane, as well as some general aspects of the properties of the red cell to facilitate understanding of events which take place through proteins molecular involvement forming the membrane

Proteomic identification of erythrocyte membrane protein deficiency in hereditary spherocytosis.

Hereditary spherocytosis (HS) is the most common congenital hemolytic anemia in Caucasians, with an estimated prevalence ranging from 1:2000 to 1:5000. The molecular defect in one of the erythrocytes (RBC) membrane proteins underlying HS like; spectrin-α, spectrin-ß, ankyrin, band 3 and protein 4.2 that lead to membrane destabilization and vesiculation, may change the RBCs into denser and more rigid cells (spherocytes), which are removed by the spleen, leading to the development of hemolytic anemia. It is classified as mild, moderate and severe, according to the degree of the hemolytic anemia and the associated symptoms. Two-dimensional gel electrophoresis (2-DE) is potentially valuable method for studying heritable disorders as HS that involve membrane proteins. This separation technique of proteins based upon two biophysically unrelated parameters; molecular weight and charge, is a good option in clinical proteomics in terms of ability to separate complex mixtures, display post-translational modifications and changes after phosphorylation. In this study, we have used contemporary methods with some modifications for the solubilisation, separation and identification of erythrocyte membrane proteins in normal and in HS RBCs. Spectrin alpha and beta chain, ankyrin and band 3 proteins expression differences were found with PDQuest software 8.0.1. and peptide mass fingerprinting (PMF) analysis performed for identification of proteins in this study.

Hereditary spherocytosis in neonates with hyperbilirubinemia.

OBJECTIVES: Hereditary spherocytosis (HS) is the most common inherited hemolytic disease among people of Northern European decent. Neonates with HS can develop significant hyperbilirubinemia, but we suspect that HS is underrecognized as a cause of neonatal jaundice. METHODS: We used electronic record repositories of Intermountain Healthcare to identify all neonates with a diagnosis of HS in a recent 5-year period. We compared these with the number of new HS cases anticipated on the basis of national prevalence and also with the number who had elevations in mean corpuscular hemoglobin concentration (MCHC), red cell distribution width (RDW), and bilirubin. We compared MCHC and RDW values of neonates who had direct antiglobulin test-positive (DAT[+]) and DAT(-) results and jaundice with values of neonates who had HS. RESULTS: Eight neonates received a diagnosis of HS; however, we may have failed to diagnose 90% of cases. To assess whether some with a missed diagnosis of HS developed significant hyperbilirubinemia, we examined records of all 670 with a bilirubin level of >or=20 mg/dL. Records of the 20 with the highest MCHC and RDW values suggested that HS was present but unrecognized in at least 7. Follow-up revealed a subsequent diagnosis of HS in 5; the other 2 are no longer in our health system. MCHC and RDW values were highest in those with HS, intermediate in the DAT(+) group, and lowest in the DAT(-) group. An MCHC of >or=36.0 g/dL had 82% sensitivity and 98% specificity for identifying HS. CONCLUSION: We speculate that HS is underrecognized as a cause of neonatal hyperbilirubinemia. We speculate further that an MCHC of >or=36.0 g/dL can alert caregivers to the possibility of HS.

[Anaemia in adopted children, not always iron deficiency]. / Anemie bij adoptiekinderen, niet altijd ijzergebrek.

Anaemia was diagnosed in four adopted children during a standard screening examination 1-4 weeks after arrival. Further investigation revealed a number of causes which could then be specifically treated. The children were a girl aged 14 months from China with iron-deficiency anaemia, a boy aged 16 months from Nigeria with sickle cell anaemia, a girl aged 5 from Haiti who had alpha-thalassaemia, and a boy aged 7 from Brazil with spherocytosis. Iron deficiency is the most common cause of anaemia in childhood. However, in adopted children from sub-tropical areas other causes of anaemia like haemoglobinopathies or erythrocyte membrane defects should be borne in mind, particularly as a history of disease and family history are often lacking. Additional investigations may be necessary. An incorrect diagnosis of iron deficiency may result in ongoing and unjustified iron supplementation leading to harmful iron accumulation in thalassaemia and a delay in the correct treatment in sickle cell anemia or spherocytosis which could carry considerable risk.

Incidence of hereditary spherocytosis in a population of jaundiced neonates.

As most of hereditary spherocytosis-affected individuals experience jaundice at birth, it seemed of interest to evaluate the proportion of hereditary spherocytosis in 402 severely jaundiced neonates with a bilirubinemia level prompting phototherapy. Red cell dehydration, a hallmark of spherocytosis whether constitutional or acquired, was demonstrated in 74 of them, among whom 23 disclosed a typical pattern of spherocytosis upon red cell deformability studies. Acquired spherocytosis of immune origin was diagnosed in 19/23 and hereditary spherocytosis in 4, making the proportion of hereditary spherocytosis-affected individuals among a severely jaundiced population of neonates amount to 1%, an incidence at least 30-fold that of the overall population.

Arteriosclerotic events are less frequent in persons with chronic anemia: evidence from families with hereditary spherocytosis.

Because anemic persons have lower cholesterol and whole blood viscosity than those who are not anemic, we hypothesized that subjects with hereditary spherocytosis who have not had the spleen removed should have fewer arteriosclerotic events than unaffected family members. We defined arteriosclerotic events as myocardial infarct, stroke, coronary artery surgery, and carotid artery surgery. We compared the rate of these events in affected-not splenectomized persons to the rate in unaffected family members. The relative risk of an arteriosclerotic event in hereditary spherocytosis patients with a spleen was one fifth that in unaffected family members. These data support the hypothesis that chronic anemia retards the development of arteriosclerosis. Spherocytosis is another example of an inherited condition that conveys an advantage in one system and a disadvantage in another.

Hereditary spherocytosis is more frequent than expected: what to tell the patient?

Modern double beam laser technique allows screening for hereditary spherocytosis in the course of routine hematology. An incidence of 1:150 men and 1:800 women has been determined. The anomaly is symptomless in the majority of the cases. This explains the discrepancy between our values and the incidence of 1:5,000 reported in the literature. The diagnosis of hereditary spherocytosis should be reported to the physician and the patient, as it may be wayleading in case of unexpected, unspecific complications such as anemia, jaundice, cholelithiasis, liver cell damage and iron overload. Regular monitoring of plasma ferritin and glucose is recommended.

Hereditary Red Cell Membrane Disorders in Japan: Their Genotypic and Phenotypic Features in 1014 Cases Studied.

This study describes the characteristic features of the incidence of hereditary red cell membrane disorders in the Japanese population based on studies of 1014 cases of these disorders from 605 kindred. Among them, there were 581 cases of hereditary spherocytosis (HS) from 303 kindred, 137 cases of hereditary elliptocytosis (HE) from 68 kindred, 104 cases of hereditary stomatocytosis (HSt) from 64 kindred, and 34 cases of protein 4.2 (P4.2) anomalies from 20 kindred, and 41 cases of membrane lipid anomalies from 27 kindred. In HS patients, eleven mutations of the band 3 (B3) gene, 15 mutations of the ankyrin gene, and three mutations of the protein 4.2 (P4.2) gene, which are pathognomonic for this disorder, were identified. Most of these mutations had not been reported and, with few exceptions, were specific to the Japanese population. P4.2 abnormalities also appear to be unique to the Japanese population. The biochemical and biophysical functions of P4.2 are associated with stabilization of the cytoskeletal network by anchoring it to integral proteins (especially B3). Biochemical and genetic analyses of the HE patients revealed one family with an α-spectrin (Sp) anomaly (HE [α(1/74)]) and three kindred with ß-spectrin abnormalities (ß-Sp Yamagata, ß-Sp Tokyo, and ß-Sp Nagoya) due to abnormal splicings of the ß-Sp gene. On the basis of these observations, the relationship between the genotypes and phenotypes is reviewed. In addition, the morphogenesis of red cell membranes with regard to the sequential expression of these membrane proteins was also discussed. Finally, from the standpoint of gene expression, a possible role of gene methylation as an epigenetic control was proposed.