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Effects of thalassemia major on bone mineral density in late adolescence.

Management of thalassemia major has shown substantial clinical and prognostic improvement, suggesting the need for major attention to quality of life. We studied bone health in 25 patients (13 males, 12 females; 15-23 years old) affected by beta-thalassemia major. In all patients, bone mineral density (BMD), biochemical markers of bone and calcium metabolism (calcium, phosphate, magnesium, alkaline phosphatase, urinary calcium, 25-hydroxyvitamin D [25OH-D], 1,25-dihydroxyvitamin D [1,25(OH)2D], parathyroid hormone [PTH]), hematological parameters and gonadal steroids status were assessed and related to each other and to auxological parameters (chronological, statural and bone ages, height, weight, stage of puberty). BMD of the lumbar spine (L1-L4) (g/cm2) and expressed as Z-scores, was assessed by dual energy X-ray absorptiometry. PTH levels were low in seven patients (28%), and in the normal range in 18 (72%). 25OH-D serum levels were normal in 16 patients (64%) and low in nine (36%). 1,25(OH)2D values were reduced in 19 patients (76%) and normal in six (24%). Alkaline phosphatase correlated with bone age delay (r = 0.414; p = 0.039); no other statistically significant correlation was found. Mean BMD values in patients with thalassemia were significantly reduced in comparison with that of age- and sex-matched controls (Z-score: -2.8 +/- 2.0, p <0.001; -3.3 +/- 2.1 in males, and -2.2 +/- 1.9 in females). Twenty-one patients (84%) showed reduced BMD. Overall, BMD reduction was in the osteopenia range in five patients (20%) and in the osteoporosis range in 16 patients (64%). Our data indicate that low BMD is often present in patients with thalassemia, although recognized late, as in the present series. Early diagnosis should be done during childhood, in order to improve the quality of life in adulthood.

Adolescent↗

[Allogeneic hematopoietic stem cell transplantation for beta-thalassemia major].

OBJECTIVE: To investigate the effect of hematopoietic stem cell transplantation (HSCT) for beta-thalassemia major. METHODS: Fifteen beta-thalassemia major patients with a median age of 3. 5 years (range 1 - 10 years) received allogeneic HSCT. According to the Pesaro's classification for thalassemia, 12 patients were grade I - II, and 3 grade III. The bone marrow transplantation (BMT) plus peripheral blood stem cell (PBSC) transplant mobilized by granulocyte colony-stimulating factor (G-CSF) was used when donor is low body-weight. RESULT: Of the fifteen patients, nine were disease-free survival (DFS) at a median follow-up of 2.5 years (range 6 - 54 months). Of eight grade I - II patients received HLA identical sibling BMT, seven were DFS, and of two received HLA mismatched marrow from their mother, one DFS, another not engrafted. Two patients received unrelated cord blood HSCT were both not engrafted. Two patients received PBSC transplantation alone were not engrafted, but one of them soon received BMT from the same donor and was DFS. The incidences of grade I - II and grade III acute graft-versus-host disease (aGVHD) were 20% (3/15) and 6.7% (1/15), respectively. Interstitial pneumonia occurred in 4/15 (26.7%) patients. There were no long-term complications in the survivors. CONCLUSION: Grade I - II beta-thalassemia major patients received HLA identical sibling BMT had higher DFS. It was propitious for engraftment to use BMT plus PBSC, but with a higher incidence of acute and chronic GVHD.

Child↗

[Ocular function in beta-thalassemia patients].

The eyes were examined in 118 inpatients with various thalassemia forms. The examinations included viso- and perimetry, biomicro- and ophthalmoscopy, fluorescent angiography of the fundus oculi and retinophotography. Patients with thalassemia were found to develop a variety of changes in the eye, whose manifestations depended on the length and severity of the underlying disease and on the treatment administered. Changes in the conjunctival and retinal vessels develop as early as in the initial stages of thalassemia, presenting as twisting, dilatation, and irregular calibre of the veins, dilatation of the arteries and reduction of their light reflex. Later dystrophic and atrophic changes develop: obliteration of the iris pattern and thinning of its peripheral zone, deterioration of blood circulation in the central retinal zone. Multiple blood transfusions and hemosiderosis lead to the development of hyperpigmentation of the limb, sclera, fundus oculi and appearance of retinal angioid strips. These findings should be taken into consideration when assessing the ocular status of thalassemia patients and defining the indications for treatment for angiopathic and dystrophic processes in the eye.

Adolescent↗

[Differential diagnosis of thalassemia syndromes].

In Sardinia, as in other areas with a high incidence of thalassemia syndromes, a prevention program based on the detection of healthy carriers through mass screening and on prenatal diagnosis in the at-risk couples has been in course for several years. The commonly adopted beta-thalassemia flow-chart consists of a first operative step involving simple and widely standardized tests: the estimation of red cell indices, the measurement of Hb A2 and Hb electrophoresis. These investigations permit the identification of the majority of the at-risk couples for beta-thalassemia. However, the not infrequent evidence of Hb A2 borderline levels, with or without microcytosis, isolated microcytosis or Hb F increased values, causes some problems in differential diagnosis, because these findings can indicate the presence of silent beta-thalassemic traits or other beta-thalassemic like states. A diagnostic definition of these unusual hematological phenotypes is particularly important for the identification of eventual at-risk couples. In this paper we report our data concerning the voluntary screening for beta-thalassemia carried out in North Sardinia. The operative flow-chart is shown. In a population with a high incidence of phenotypically heterogeneous thalassemic syndromes, such as that of Sardinia, differential diagnosis of thalassemic traits can require molecular studies. This molecular characterization, which could be carried out in specialized reference centers, is today absolutely necessary both for exact identification of at-risk couples and eventual prenatal diagnosis.

Adult↗

Interaction of hemoglobin E and several forms of alpha-thalassemia in Cambodian families.

BACKGROUND AND OBJECTIVES: This study aimed to describe hematologic and molecular characterization of the interaction of hemoglobin (Hb) E and several forms of alpha-thalassemia causing complex thalassemia syndromes in two Cambodian families as well as to establish a rapid polymerase chain reaction (PCR) assay for simultaneous detection of Hb Constant Spring (CS) and Hb Pakse' (PS). DESIGN AND METHODS: Using PCR and DNA sequencing, the alpha- and beta-globin genotypes were examined. Clinical and hematologic data were assessed. A multiplex asymmetric allele-specific PCR for differential diagnosis of HbCS and HbPS was developed and validated. RESULTS: Eight genotypes including heterozygous HbCS, heterozygous HbPS, double heterozygous HbE/HbPS, double heterozygous HbE/alpha-thalassemia 2, triple heterozygous HbE/alpha-thalassemia /HbPS, homozygous HbE/alpha-thalassemia 2, compound alpha-thalassemia 2/HbCS and a hitherto undescribed compound HbCS/HbPS were found in these two families. Genotype-phenotype relationships are discussed and successful application of a multiplex PCR system for differential diagnosis of HbCS and HbPS is described. INTERPRETATION AND CONCLUSIONS: The interaction of several globin gene abnormalities in Cambodian families emphasizes the high frequencies of thalassemia and hemoglobinopathies. Identification of HbPS suggests that this mutation might be common and underestimated among South-east Asian populations. A simplified PCR assay for simultaneous detection of HbCS and HbPS would facilitate characterization of these genotypes in both the clinical setting and population screening programs in the region.

Adolescent↗

Delta-thalassemia caused by disruption of the site for an erythroid-specific transcription factor, GATA-1, in the delta-globin gene promoter.

Delta-thalassemia is a complex group of inherited disorders of globin genes characterized by impaired synthesis of the delta-globin chain. The T-C substitution was detected at position -77 of the delta-globin gene isolated from three independent Japanese individuals who were homozygotes for delta-thalassemia. To elucidate the significance of the mutation in delta-globin gene expression, we investigated the genotype of three delta-thalassemia homozygotes and 58 normal individuals using dot blot hybridization of the polymerase chain reaction (PCR)-amplified DNA. The mutation was observed in six alleles of three homozygotes, while no mutation was detected in 116 alleles of normal individuals, thereby indicating the close association of this mutation with the thalassemia phenotype. Since the mutation (TTATCT-TCATCT) is located within the inverted binding motif of GATA-1 (T or A-G-A-T-A-G or A), an erythroid cell-specific transcription factor, we did gel retardation assays using nuclear extracts from the erythroid cells. We found that GATA-1 binds the oligonucleotide spanning positions -61 to -90, but does not bind to the oligonucleotide with the mutation at position -77. Competition gel retardation assays showed that GATA-1 binding can be competed out by the fragment with the GATA-1 motif, but not with the mutant oligonucleotide. Analysis of the transient expression of the CAT gene linked to the delta-globin gene promoter region demonstrated that the construct with the mutant promoter region was expressed about 20-fold less compared with the normal one. Thus, the mutation at position -77 impairs delta-globin gene expression by abolishing GATA-1 binding to the AGATAA sequence of the promoter region of the delta-globin gene. This provides a good example of involvement of tissue-specific transacting factors in the molecular pathogenesis of hereditary diseases.

Base Sequence↗

Bone marrow transplantation in adult thalassemia.

Early trials of allogeneic marrow transplantation for homozygous thalassemia were disappointing in patients older than 16, with four of six patients dying early of graft-versus-host disease-related complications, one patient dying at 9 months of infection due to graft failure, and one dying at 6 years of recurrent thalassemia. Three classes of risk could be identified in analyses of results of transplantation in younger patients using the criteria of degree of hepatomegaly, the presence or absence of portal fibrosis, and a history of adequate or inadequate chelation therapy. Patients for whom all three criteria were adverse constituted a very high risk group (class 3) for marrow transplantation. On the basis of these analyses, a conditioning regimen was designed that yielded superior results for class 3 patients under 17 years of age. Most patients older than 16 years presenting for transplantation have disease characteristics that place them in class 3 and, because of the improved results with the new class 3 regimen in younger patients, a study was designed to treat patients older than 16 years using treatment regimens assigned on the basis of disease class. Twenty patients were treated using this protocol and, with a minimum follow-up of 9 months, there have been three early deaths, one patient has recurrent thalassemia, and 16 patients are alive disease-free. The actuarial probabilities of survival, disease-free survival, and rejection are 0.85, 0.80, and 0.05, respectively, with a survival plateau extending from 6 months to 3 years. Marrow transplantation is a reasonable option for adults with progressive thalassemia who have suitable donors.

Adolescent↗

[Multiplex PCR for detecting genotypes of deletional alpha-thalassemia].

To investigate the clinical application of multiplex PCR in detecting genotypes of deletional alpha-thalassemia in South China and observe the distribution frequency of alpha-globin gene deletion, 145 patients with silent carrier, alpha thalassemia trait or HbH were identified by M-PCR and 1.2% agarose gel electrophoresis. There are 1.3, 1.6, 1.8 and 2.0 kb bands which indicate --(SEA), -alpha(4.2), alphaalpha and -alpha(3.7), respectively. The results showed that among 145 patients, 100 patients with --(SEA)/alphaalpha (68.9%), 15 with -alpha(3.7)/alphaalpha (10.3%), 8 with -alpha(4.2)/alphaalpha (5.52%), 2 with -alpha(3.7)/-alpha(4.2) (1.38%), 1 with -alpha(3.7)/-alpha(3.7) (0.69%), 1 with -alpha(4.2)/-alpha(4.2) (0.69%), 14 with --(SEA)/-alpha(3.7) (9.65%), 2 with --(SEA)/-alpha(4.2) (1.38%) were found. Two patients prenatal diagnosed were confirmed with Bart's hydrops fetuses. In conclusion, M-PCR analysis is a simple, rapid and accurate method for detection of alpha-thalassemia gene deletion. This technique is helpful in screening, carrier identification and prenatal diagnosis of deletional alpha-thalassemia.

Adolescent↗

Reduction of tissue iron stores and normalization of serum ferritin during treatment with the oral iron chelator L1 in thalassemia intermedia.

In patients with thalassemia intermedia in whom hyperabsorption of iron may result in serious organ dysfunction, an orally effective iron-chelating drug would have major therapeutic advantages, especially for the many patients with thalassemia intermedia in the Third World. We report reduction in tissue iron stores and normalization of serum ferritin concentration after 9-month therapy with the oral chelator 1,2-dimethyl-3-hydroxypyrid-4-one (L1) in a 29-year-old man with thalassemia intermedia and clinically significant iron overload (SF 2,174 micrograms/L, transferrin saturation 100%; elevated AST and ALT, abnormal cardiac radionuclide angiogram) who was enrolled in the study with L1 75 mg/kg/day after he refused deferoxamine therapy. L1-Induced 24-hour urinary iron excretion during the first 6 months of therapy was (mean +/- SD, range) 53 +/- 30 (11 to 109) mg (0.77 mg/kg), declining during the last 3 months of L1 to 24 +/- 14 (13-40) mg (0.36 mg/kg), as serum ferritin decreased steadily to normal range (present value, 251 micrograms/L). Dramatic improvement in signal intensity of the liver and mild improvement in that of the heart was shown by comparison of T1-weighted spin echo magnetic resonance imaging with images obtained immediately before L1 administration was observed after 9 months of L1 therapy. Hepatic iron concentration decreased from 14.6 mg/g dry weight of liver before L1 therapy to 1.9 mg/g liver after 9 months of therapy. This constitutes the first report of normalization of serum ferritin concentration in parallel with demonstrated reduction in tissue iron stores as a result of treatment with L1. Use of L1 as a therapeutic option in patients with thalassemia intermedia and iron overload appears warranted.

Adult↗

[Successful preimplantation genetic diagnosis for beta-thalassemia using multiplex nested polymerase chain reaction].

OBJECTIVE: To develop single-cell multiplex nested polymerase chain reaction (PCR) assays for preimplantation genetic diagnosis (PGD) in couples at risk of having child with beta-thalassemia. METHODS: Primers were designed and synthesized according to the documented mutation sites common among Chinese. Venous blood was collected from 4 pairs of husband and wife, all heterozygotes for beta-thalassemia, and underwent multiple nested PCR. Intraooplasmic sperm injection and mechanical bio psy was used to obtain single blastomere. Multiplex nested PCR was used to detect the CD41-42 mutation and the closely linked polymorphic marker, HumTHO1 gene or CD41-42, CD41-28, IVSII654 mutation and HumTHO1 gene in the single blastomeres from four clinical PGD cycles. The normal embryos with high scores capable of continuing to divide were transplanted into the uteri. The process of gestation was observed. RESULTS: 200 lymphocytes were amplified by nested PCR. The average amplification rate of the most common 16 beta-thalassemia mutations in Chinese population was 91.3% and the average rate of allele drop out for different sites was 17.0% without differences between any 2 sites. During the 4 PGD cycles 33 embryos underwent bioassay with a success rate of 100%. 33 blastomeres were obtained to undergo PCR, of which 30 were successfully amplified with an amplification rate of 90.9%. Explicit diagnosis was obtained in 26 of the 30 embryos: 7 normal homozygotes, 11 heterozygotes, and 8 abnormal or complex heterozygotes. One or more embryos were transferred back into the uteri of the 4 women and clinical pregnancy occurred in one woman. Five weeks after the implantation B-mode ultrasonography showed monocyesis, and in the 17th week of gestational period paracentesis of cord blood showed normal homozygote. At last a normal female infant confirming the PGD result had been born, which was the first reported unaffected pregnancy resulting from PGD using multiplex nested PCR for couples as beta-thalassemia gene carriers. The results of diagnosis for embryo all corresponded to those for blastomere. The average ADO rate of blastomere was 13.3% (4/30). CONCLUSION: PGD using multiplex nested PCR, as an alternative to prenatal diagnosis, is a reliable and effective way to help couples-carriers of pathogenetic genes to get a healthy baby.

Adult↗

Cord blood analysis for prenatal diagnosis of thalassemia major and hemophilia A.

Beta thalassemia and Hemophilia A are common genetic disorders for which prenatal diagnosis (PND) is an accepted option. Our aim was to evaluate cord blood analysis as a method for PND of these disorders. Cord blood samples at 18-26 weeks gestation from nine mothers with previous thalassemia major child and five families with previous hemophilia A were studied. In the former; HbF, HbA2 and HbF were determined by high performance liquid chromatography (HPLC) and in latter; Factor VIII and IX assays were done by one stage method. In HPLC studies for thalassemia, three out of nine fetuses were affected, five were carriers and one was normal. In hemophilia PND samples, 2 out of five fetuses were affected. Thus, HPLC and factor VIII assay in cord blood are feasible alternatives for PND in Beta thalassemia and hemophilia A respectively, especially when DNA analysis is uninformative or there are financial constraints.

Female↗

[Successful preimplantation genetic diagnosis for alpha-thalassemia using fluorescent polymerase chain reaction].

OBJECTIVE: To develop single-cell fluorescent gap polymerase chain reaction (PCR) assay for preimplantation genetic diagnosis (PGD) in couples at risk of having child with alpha-thalassemia. METHODS: Single cell fluorescent gap PCR which can detect the alpha-thalassemia Southeast Asia deletion (-SEA deletion), was applied to single lymphocytes and blastomeres which coming from four clinical PGD cycles. RESULTS: The Single cell fluorescent gap PCR can detect the alpha-thalassemia -SEA deletion, which account for 94% of hydrop fetalis in Chinese population with an amplification efficiency of 90.0% (72/80) and allele drop-out (ADO) rate of 8.3% (6/72) in lymphocytes. In four clinical PGD cycles, a total 38 embryos were detected and 38 blastomeres were obtained. Thirty-four blastomeres were amplified with the amplification efficiency of 89.5% (34/38) and ADO rate of 5.9% (2/34). Eleven embryos were shown to be normal homozygous, eight embryos were shown to be heterozygous and 15 embryos were shown to be affected homozygous. Eleven embryos were transferred back to the uterus of the patients. Two pregnancy achieved, resulting in two live healthy births, which confirmed the results of PGD. CONCLUSION: This first reported unaffected pregnancy resulting from PGD using fluorescent gap PCR for alpha-thalassemia demonstrates that this technique, as an alternative to prenatal diagnosis, is a reliable and effective way to help those carrier couples to get a healthy baby.

Adult↗

De novo and acquired forms of alpha thalassemia.

Alpha thalassemia is a genetic disorder of hemoglobin production that typically is inherited in an autosomal co-dominant fashion. Rare forms of alpha-thalassemia, however, occur as de novo or acquired disorders. These disorders occur in two clinical situations: 1) alpha-thalassemia associated with mental retardation, and 2) acquired alpha-thalassemia (HbH disease) associated with myelodysplastic syndrome. Study of these rare disorders has led to the identification and characterization of a gene on the X chromosome (called ATRX) that encodes a trans-acting factor capable of influencing the expression of alpha-globin and other genes.

DNA Helicases↗

The benefits of vitamin C and vitamin E in children with beta-thalassemia with high oxidative stress.

UNLABELLED: The present study aimed to determine the benefits of vitamin C and vitamin E as antioxidant supplements in beta-Thalassemia children who are at risk of iron overload due to multiple blood transfusion and high oxidative stress. Antioxidant status, oxidative products, plasma free hemoglobin, total hemoglobin and bilirubin were discussed. Twenty children who had laboratory confirmation of major beta-Thalassemia at least 6 months with history of packed red cell transfusion without iron chelation were recruited. The informed consent for blood sample collection and antioxidant medication was performed. Most patients (85%) had hyperferritinemia and all of them had high oxidative stress. All of them had low vitamin C and vitamin E level at recruitment. Three months after vitamin C and vitamin E supplementation, plasma vitamin C, vitamin E and glutathione were significantly increased, while total bilirubin was slightly decreased without significance. Other parameters included total antioxidant status (TAS), plasma and erythrocyte malondialdehyde (MDA), hemoglobin and plasma free hemoglobin had no differences during the study period. CONCLUSION: B-Thalassemia major children who had multiple blood transfusion are at risk in iron overload and high oxidative stress. From the present study, no significant improvement in raising hemoglobin and concerning low dose vitamin C is not contraindication in beta-Thalassemia patients. Therefore, vitamin C plus vitamin E supplementation have benefits more than vitamin E alone in promoting antioxidant status and may enhance liver function as total bilirubin tends to decrease.

Adolescent↗

Serum and erythrocyte levels of magnesium in microcytosis: comparison between heterozygous beta-thalassemia and sideropenic anemia.

In thalassemia erythrocyte cation permeability is increased, but the increment in ATPase-dependent cation pumps maintains normal concentrations of Ca++, Na+ and K+. In this study we investigated erythrocyte concentrations of Mg++ in heterozygous beta-thalassemia and in microcytic sideropenic anemia. Twenty-five healthy controls, 40 heterozygous beta-thalassemics and 25 patients with sideropenic anemia were studied. Erythrocyte Mg++ was assayed either by atomic absorption or by standard laboratory methods. Erythrocyte Mg++ was significantly lower in the beta-thalassemia group than in the other two groups (p less than 0.001). Serum magnesium was significantly lower in sideropenic anemia patients than in beta-thalassemics and in controls (p less than 0.01), whereas these latter two groups showed similar values. Our results suggest that the increment in ATPase-dependent cation pumps is not sufficient to maintain normal erythrocyte Mg++ concentrations in heterozygous beta-thalassemia. In sideropenic anemia cation permeability is not increased, therefore erythrocyte Mg++ is normal. Low serum Mg++ levels in sideropenic anemia could be explained by a primary Mg++ deficit associated with sideropenia.

Adolescent↗

[Clinical observation on effects of Yisui Shengxue Granule in treating 156 patients with beta-thalassemia].

OBJECTIVE: To study the clinical effect and security of Yisui Shengxue Granule (YSG) in treating beta-thalassemia. METHODS: One hundred and fifty-five patients with beta-thalassemia from high-incidence area in Guangxi Zhuang Autonomous Region were treated with YSG for 3 months. Clinical symptoms and levels of hemoglobin (Hb), red blood cell (RBC), reticulocyte (Ret) and hemoglobin F (HbF) were observed before and after treatment, and the adverse reaction occurred in the therapeutic course was observed as well. A 3-6 months follow-up study was performed after withdrawal of YSG. RESULTS: Levels of Hb, RBC, Ret and HbF obviously elevated, and clinical symptoms markedly improved in patients after treatment since the 1st month to the 3rd month (all P < 0.01). Dynamical observation showed that the improvement of symptoms was in accordance with the elevation of hemorrheological indexes. The treatment was effective in 145 patients and ineffective in 11, and the total effective rate being 92.9%, without any adverse reaction occurred. Follow-up study showed the therapeutic effect could be sustained for 3 to 4 months. CONCLUSION: YSG has evident effect on alpha-thalassemia without obvious adverse reaction, which provides a definite basis for treatment of beta-thalassemia with TCM.

Adolescent↗

Haptoglobin levels are associated with haptoglobin genotype and alpha+ -Thalassemia in a malaria-endemic area.

Haptoglobin (Hp) is an acute phase protein that removes free hemoglobin (Hb) released during hemolysis. Hp has also been shown to be toxic for malaria parasites. alpha(+)-Thalassemia is a hemoglobinopathy that results in subclinical hemolytic anemia. alpha(+)-Thassemia homozygosity confers protection against severe malarial disease by an as yet unidentified mechanism. Hp levels were measured in a serial cross-sectional survey of children in Madang Province, Papua New Guinea (PNG). Hp levels were related to age, Hp genotype, Hb levels, parasitemia, splenomegaly, and alpha(+)-thalassemia genotype. Surprisingly, children who were homozygous for alpha(+) -thalassemia had significantly higher levels of Hp than did heterozygotes, after controlling for relevant confounders. We suggest that this is the result of either reduced mean cell Hb associated with alpha(+) -thalassemia homozygosity or an elevated IL-6-dependent acute phase response.

Adolescent↗

Common queries in thalassemia care.

Beta thalassemia is a common genetic disorder in Indians. Around 10,000 thala-ssemia major cases are born every year. The treatment of thalassemia major patients imposes a financial burden on the family. Much progress has been made in last 15 years in understanding of the pathogenesis of thalassemia and development of effective management(1). These include development of a promising new oral iron chelator, intensive preparative regimens for stem cell transplantation and better vectors for gene therapy. In the present article, we highlight the common questions asked by the family and the general practitioners on thalassemia care.

Blood Transfusion↗