20 years review of antenatal diagnosis of haemoglobin Bart's disease and treatment with intrauterine transfusion.

OBJECTIVE: To review prenatal diagnosis and outcome of alpha thalassaemia major through universal antenatal screening. METHOD: This was a retrospective study on ultrasound features, antenatal diagnosis, in-utero intervention and long term outcome of pregnancies at risk of Haemoglobin Bart's hydrops foetalis syndrome attending prenatal diagnosis from 2000 to 2019 at Tsan Yuk Hospital in Hong Kong. RESULTS: Among 390 foetuses from 373 at-risk pregnancies, 122 (31%) prenatal invasive procedures were performed and 65 affected foetuses were diagnosed antenatally. For foetuses with ultrasound features of anaemia, the diagnostic yield of BHFS was 73%. Cardiomegaly carried a positive predictive value of 65.2% while its absence had the highest negative predictive value (96.0%). Three women having affected foetuses continued pregnancy and received intrauterine transfusion beginning 20 weeks of gestation. All babies were born alive and non-hydropic. They were managed with regular transfusion and cured by haematopoietic stem cell transplantation. CONCLUSIONS: Absence of ultrasound features of anaemia had high negative predictive value for alpha thalassaemia major. Couple at risk of having affected foetus could be offered serial ultrasound surveillance. Invasive testing for pregnancies with features of foetal anaemia provided high diagnostic yield. Intrauterine transfusion corrected foetal anaemia and allowed long term transfusion free survival without significant neurological sequelae following postnatal transplant therapy.

Advances in the management of α-thalassemia major: reasons to be optimistic.

α-Thalassemia major (ATM) is a severe disease resulting from deletions in all 4 copies of the α-globin gene. Although it is usually fatal before birth, the advent of in utero transfusions has enabled survival of a growing number of children. Postnatal therapy consists of chronic transfusions or stem cell transplantation, similar to patients with ß-thalassemia major. In this review, we discuss the experience with postnatal stem cell transplantation in patients with ATM, as well as the ongoing phase 1 clinical trial of in utero stem cell transplantation for this condition.

ATR-X syndrome: genetics, clinical spectrum, and management.

ATR-X, an acronym for alpha thalassemia and mental retardation X-linked, syndrome is a congenital condition predominantly affecting males, characterized by mild to severe intellectual disability, facial, skeletal, urogenital, and hematopoietic anomalies. Less common are heart defects, eye anomalies, renal abnormalities, and gastrointestinal dysfunction. ATR-X syndrome is caused by germline variants in the ATRX gene. Until recently, the diagnosis of the ATR-X syndrome had been guided by the classical clinical manifestations and confirmed by molecular techniques. However, our new systematic analysis shows that the only clinical sign shared by all affected individuals is intellectual disability, with the other manifestations varying even within the same family. More than 190 different germline ATRX mutations in some 200 patients have been analyzed. With improved and more frequent analysis by molecular technologies, more subtle deletions and insertions have been detected recently. Moreover, emerging technologies reveal non-classic phenotypes of ATR-X syndrome as well as the description of a new clinical feature, the development of osteosarcoma which suggests an increased cancer risk in ATR-X syndrome. This review will focus on the different types of inherited ATRX mutations and their relation to clinical features in the ATR-X syndrome. We will provide an update of the frequency of clinical manifestations, the affected organs, and the genotype-phenotype correlations. Finally, we propose a shift in the diagnosis of ATR-X patients, from a clinical diagnosis to a molecular-based approach. This may assist clinicians in patient management, risk assessment and genetic counseling.

CRISPR/Cas9 gene correction of HbH-CS thalassemia-induced pluripotent stem cells.

Haemoglobin (Hb) H-constant spring (CS) alpha thalassaemia (- -/-αCS) is the most common type of nondeletional Hb H disease in southern China. The CRISPR/Cas9-based gene correction of patient-specific induced pluripotent stem cells (iPSCs) and cell transplantation now represent a therapeutic solution for this genetic disease. We designed primers for the target sites using CRISPR/Cas9 to specifically edit the HBA2 gene with an Hb-CS mutation. After applying a correction-specific PCR assay to purify the corrected clones followed by sequencing to confirm the mutation correction, we verified that the purified clones retained full pluripotency and exhibited a normal karyotype. This strategy may be promising in the future, although it is far from representing a solution for the treatment of HbH-CS thalassemia now.

Clinical Classification, Screening and Diagnosis for Thalassemia.

At present, thalassemia diseases are classified into transfusion-dependent thalassemia and non-transfusion-dependent thalassemia. This classification is based on the clinical severity of patients determining whether they do require regular blood transfusions to survive (transfusion-dependent thalassemia) or not (non-transfusion-dependent thalassemia). In addition to the previous terminology of "thalassemia major" or "thalassemia intermedia," this classification has embraced all other forms of thalassemia syndromes such as α-thalassemia, hemoglobin E/ß-thalassemia and combined α- and ß-thalassemias. Definitive diagnosis of thalassemia and hemoglobinopathies requires a comprehensive workup from complete blood count, hemoglobin analysis, and molecular studies to identify mutations of globin genes.

Elevations of Thrombotic Biomarkers in Hemoglobin H Disease.

BACKGROUND: Thalassemia is a group of hereditary hemoglobinopathies caused by decreased or absent synthesis of α and/or ß globin chains. Studies have shown that hypercoagulability and thrombosis are common clinical symptoms in ß-thalassemia, especially ß-thalassemia intermedia, but little is known about in α-thalassemia. This study aims to examine phosphatidylserine (PS) levels, platelet activation, and coagulation markers in splenectomized (S) and nonsplenectomy (NS) patients with hemoglobin (Hb) H disease. METHODS: The NS group comprised 20 patients (median age 15.0 years, range, 14-16.5 years), and the S group consisted of 11 patients (median age 16.4 years, range, 14-19.9 years) with Hb H disease; the control group consisted of 20 normal subjects. Hematological parameters were collected. Flow cytometry was used to measure PS exposure on red blood cells. The levels of intercellular adhesive molecule (ICAM)-1, tumor necrosis factor α (TNFα), ß-thromboglobulin (TG) and prothrombin fragment 1 + 2 (F1.2) were determined using ELISA test kits. RESULTS: Significant increases in the levels of PS, ICAM-1, TNFα, ß-TG, and F1.2 were observed in both patient groups compared to normal controls (p < 0.01). CONCLUSION: This observation indicates blood coagulation, endothelial injury, chronic low-grade inflammation, platelet activation, and thrombin generation are present in Hb H disease; these findings merit further assessment in a larger prospective cohort to establish possible links with thrombotic manifestations.

Clinical management of the homozygous α-thalassemia with unusual mandibular manifestation of hematopoiesis.

Alpha (α)-thalassemias are the most common genetic disorder of hemoglobin (Hb) synthesis, affecting up to 5% of the world's population. These congenital hemolytic anemias induce extramedullary hematopoiesis, including the liver, spleen, sinuses, and the diploic spaces of the skull. Oral health problems in patients with thalassemias are mostly related to a varied degree of facial deformities, malocclusions, and/or dental arch dimensions. We present a case with a 49-year-old man, diagnosed with homozygous α thalassemia that came to the Faculty of Dentistry at the University of Murcia for a dental treatment. It was observed that the patient had an unusual mandibular manifestation of hematopoiesis.

Homozygous α-thalassemia: Challenges surrounding early identification, treatment, and cure.

The prognosis for homozygous α-thalassemia is changing. Prenatal diagnosis and intrauterine transfusions (IUT) reduce maternofetal morbidity and mortality; hematopoietic stem cell transplant (HSCT) is curative. Empiric evidence to support IUT and HSCT to treat homozygous α-thalassemia is lacking. The first case of curative HSCT for homozygous α-thalassemia was reported in 1997. Nearly 20 years later, five additional reports are published. We review the literature and report an institutional experience with three homozygous α-thalassemia patients. The first died shortly after birth. The second underwent HSCT after years of chronic transfusion therapy. The third benefited from IUT and HSCT. These cases exemplify the varied outcomes associated with this condition.

Favorable outcomes after in utero transfusion in fetuses with alpha thalassemia major: a case series and review of the literature.

OBJECTIVE: Alpha thalassemia major (ATM) is often fatal in utero due to severe hydrops fetalis. Although in utero transfusions (IUTs) are increasingly used to allow fetal survival in ATM, prenatal and postnatal outcomes are not well described. METHODS: We retrospectively reviewed cases of ATM at our institution treated with consecutive IUT. Clinical records were reviewed for transfusion history, neurodevelopmental outcomes, anatomic abnormalities, survival to hematopoietic cell transplantation, and transfusion independence. A systematic review was performed, and additional reported cases are discussed. RESULTS: Three patients who underwent IUT for ATM were identified, and review of the literature revealed 17 reported cases. Of patients who received IUT, reported neurodevelopmental deficits occurred in 29% (4/14) and anatomic abnormalities in 55% (11/20). Four patients eventually underwent successful hematopoietic cell transplantation. Transfusion volumes were less than suggested guidelines for other causes of fetal anemia in 91.7% of the transfusions. CONCLUSION: This series demonstrates the potential for achieving full fetal development with normal neurologic outcomes in those affected by ATM. It provides support for continued patient and provider education about current benefits and risks of active prenatal therapy for fetuses with ATM, as well as continued research to optimize therapeutic strategies such as in utero transplantation. © 2016 John Wiley & Sons, Ltd.

Curative Stem Cell Transplantation for Severe Hb H Disease Manifesting From Early Infancy: Phenotypic and Genotypic Analyses.

Most people with Hb H disease live normal lives; however, a minority of cases requires lifelong regular transfusions. An atypical form of nondeletional Hb H disease was reported in a Thai boy, characterized by severe persistent hemolytic anemia since the age of 2 months. Molecular diagnosis revealed the apparent compound heterozygosity for the Southeast Asian (- -(SEA)) and α2 polyadenylation (polyA) signal (AATAAA>AATA- -) deletions. The proband was successfully treated with allogeneic hematopoietic stem cell transplantation (HSCT). Accurate phenotypic and genotypic diagnosis in atypically severe Hb H disease is helpful for the understanding of its pathophysiology, the institution of appropriate management, and provision of genetic counseling and prenatal diagnosis. Hematopoietic stem cell transplantation is a potentially curative treatment option for this severe α-thalassemia (α-thal) syndrome.

Discrimination of various thalassemia syndromes and iron deficiency and utilization of reticulocyte measurements in monitoring response to iron therapy.

Decreased hemoglobinization of red cells resulting in hypochromia and microcytosis are the main features of thalassemia syndromes, and also of iron deficiency anemia (IDA). A simple and reliable method is required to distinguish the two conditions in the routine laboratories. In this study we analyzed the red cell and reticulocyte parameters from 414 samples of various types of thalassemias and IDA and discovered a variety of discriminating criteria including a discrimination index (DI) which should be useful for differential diagnosis. Slightly decreased MCV and CH are suggestive of α-thalassemia 2, Hb CS, and Hb E heterozygotes whereas the increased Rbc counts are obvious in α-thalassemia 1 and ß-thalassemia. In Hb E, the number of microcytic red cells was greater than the number of hypochromic red cells resulting in an increased M/H ratio. Hb H diseases are characterized by a higher number of hypochromic red cells and decreased CHCM, while broadening of hemoglobin concentration histogram results in increased HDW in ß-thalassemia diseases. Iron deficiency anemia results in hypochromic-microcytic red cells and increased RDW. The number of reticulocyte with %High Retic and CHr value were increased in the first month of iron supplementation indicating the response to iron therapy.

[Current management of thalassemia intermedia]. / Prise en charge actuelle des thalassémies intermédiaires.

Thalassemia intermedia is a clinical entity where anemia is mild or moderate, requiring no or occasional transfusion. Non-transfusion-dependent thalassemia encompasses 3 main clinical forms: beta-thalassemia intermedia, hemoglobin E/beta-thalassemia and alpha-thalassemia intermedia (HbH disease). Clinical severity of thalassemia intermedia increases with age, with more severe anemia and more frequent complications such as extramedullary hematopoiesis and iron overload mainly related to increased intestinal absorption. Numerous adverse events including pulmonary hypertension and hypercoagulability have been associated with splenectomy, often performed in thalassemia intermedia patients. The potential preventive benefit of transfusion and chelation therapies on the occurrence of numerous complications supports the strategy of an earlier therapeutic intervention. Increasing knowledge about pathophysiological mechanisms involved in thalassemia erythropoiesis and related iron overload is currently translating in novel therapeutic approaches.

Splenectomy improves anaemia but does not reduce iron burden in patients with haemoglobin H Constant Spring disease.

BACKGROUND: Splenectomy is reported to increase the haemoglobin level in patients with haemoglobin H Constant Spring (HbH CS) disease; however, its impact on iron burden and the underlying mechanism remains unclear. MATERIALS AND METHODS: From March through to May 2013, a total of 50 adults with HbH CS disease (25 cases splenectomised and 25 cases non-splenectomised) were enrolled. The patients' general conditions, history of blood transfusion and iron chelator treatment were investigated. Levels of haemoglobin, nucleated red blood cell counts, and serum ferritin were measured. The percentage of apoptotic erythroid precursor cells in bone marrow, an index representing ineffective erythropoiesis, was determined in some cases. RESULTS: There were no significant differences in age, blood transfusion volume, and use of iron chelator drugs between the splenectomised group and the non-splenectomised group. Significantly higher haemoglobin levels, serum ferritin levels and nucleated red blood cell counts as well as a higher percentage of apoptotic erythroid progenitor cells were detected in the splenectomised group. Regression analysis revealed that age and nucleated red blood cell counts were independent risk factors affecting the serum ferritin level. DISCUSSION: Despite improving the haemoglobin level, splenectomy is associated with greater iron burden in HbH CS disease. A high nucleated red blood cell count is predictive of the risk of severe iron overload.

X-linked mental deficiency.

Ten percent of cases of intellectual deficiency in boys are caused by genes located on the X chromosome. X-linked mental retardation (XLMR) includes more than 200 syndromes and 80 genes identified to date. The fragile X syndrome is the most frequent syndrome, due to a dynamic mutation with a CGG triplet amplification. Mental retardation is virtually always present. Phonological and syntactic impairments are often combined with pragmatic language impairment and visuospatial reasoning difficulties. A minority fulfill the criteria for autism. In girls, the clinical expression of the complete mutation varies according to the X chromosome inactivation profile. Several XLMR occur as severe early onset encephalopathies: Lowe oculocerebrorenal syndrome, ATR-X syndrome (alpha thalassemia/mental retardation X-linked), Allan-Herdon-Dudley syndrome (MCT8 gene). Two genes, ARX (X-LAG; Partington syndrome) and MECP2 (Rett syndrome in females; mild MR with spastic diplegia/psychotic problems in males) are associated with various phenotypes, according to the mutation involved. Oligophrenine 1 (OPHN-1) gene mutations lead to vermal dysplasia. PQBP1 gene mutations (Renpenning syndrome) are responsible for moderate to severe mental deficiency, microcephaly, and small stature. Although some forms of XLMR are not very specific and the phenotype for each given gene is somewhat heterogeneous, a clinical diagnostic strategy is emerging.

Successful unrelated cord blood transplantation for homozygous α-thalassemia.

A now 10-year-old Laotian female was delivered at 30-week gestation by cesarean section because of severe hydrops. Fetal blood sampling revealed homozygous α-thalassemia. After immediate resuscitation, the infant was supported with frequent red cell transfusions. At 44 months of age, she received a 5 of 6 human leukocyte antigen-matched unrelated cord blood transplantation. She was treated with phlebotomy and chelation therapy with Deferasirox for correction of hemosiderosis and has been transfusion-independent since 41 days after transplant. She is currently 6 years after transplantation with stable, 100% donor engraftment, resolved iron overload, and normal growth and development.

A new ATRX mutation in a patient with acquired α-thalassemia myelodysplastic syndrome.

Acquired α-thalassemia (α-thal) myelodysplastic syndrome (ATMDS) is a rare acquired syndrome characterized by a somatic point mutation in the ATRX gene in patients with chronic myeloid disorders. We describe the case of a 78-year-old man with myelodysplastic syndrome (MDS) and striking microcytic, hypochromic anemia. Brilliant cresyl blue supravital stain of the peripheral blood and hemoglobin (Hb) electrophoresis showed the presence of Hb H. Sequence analysis of unfractionated peripheral blood DNA identified a G>T transition at codon 524 in exon 7 of the ATRX gene. To the best of our knowledge, it is the first description of this point mutation of the ATRX gene in an ATMDS.

The incidence of hepatitis C in patients with thalassemia after screening in blood transfusion centers: a fourteen-year study.

BACKGROUND: Blood safety is important in all transfusion centers. The aim has always been to try to guarantee the recipient's safety through careful screening and examination of donors' blood samples. In Iran the hepatitis C virus (HCV) screening test became mandatory for blood donations from 1996. We decided to determine the incidence of new cases of HCV in patients with thalassemia, after screening of blood bags was initiated. STUDY DESIGN AND METHODS: The study was done on patients with complete files for anti-HCV test results. Only cases that had a confirmed positive anti-HCV result after a negative result were considered as new cases. The incidence rate was estimated and expressed in person-years (PY). Also, for increased accuracy and comparison of incidence in recent years, the incidence rate was calculated at two 7-year intervals (1996-2002 and 2003-2009). RESULTS: A total of 395 files were studied with a mean age of 27.5 years (SD ± 7.99 years). We had 109 (27.5%) anti-HCV positive, of which 21 (19.2% of positive cases) were exposed after 1996 and considered as new cases. The incidence of HCV cases in 14 years (1996-2009) was 4.2/1000 PY. The incidence in the first 7-year period (1996-2002) was 6.2/1000 PY and 1.3/1000 PY in the second 7-year period (2003-2009). CONCLUSION: The incidence of HCV is on the decline in Iran, both in blood donors and in recipients. We owe this to the improved blood safety in our transfusion center that has taken up better strategies. Even though the residual risk will never reach zero and we may still have new cases of HCV, it will definitely be with a lower rate. The fact that we have had no new cases among our patients with thalassemia since 2005 bears witness to this matter.