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PubMed2006

Non-Hodgkin disease in beta-thalassemia major.

Thalassemia is a spectrum of diseases characterized by the decrease or absence of globin chains. The occurrence of lymphoma in thalassemia has rarely been reported, and our review of the English literature revealed only four cases. Because anemia is always masked by regular transfusions in thalassemic patients, physicians discover a hidden malignancy late in the course of the disease. We hereby report the case of a thalassemic patient developing non-Hodgkin disease and discuss the possibility of a link between the two disease entities. This case is intended to alert physicians of the possibility of a malignancy in thalassemia patients.

Adult↗
PubMed2006

Reticulocyte evaluation in alpha(+)-thalassemia.

Although it is almost certain that alpha(+)-thalassemia protects against malaria, the mechanisms for that are still unknown. It has been suggested that an increased number of young circulating red blood cells in alpha(+)-thalassemic children, as a result of some degree of ineffective erythropoiesis, could be related to the high frequencies of the alpha(+)-thalassemic allele in malaria endemic areas. Reticulocyte evaluation in this condition, however, has been poorly performed so far. Our objective was to determine the reticulocyte number and maturation degree, in addition to the soluble transferrin receptor and serum erythropoietin levels, in alpha(+)-thalassemia heterozygotes, comparing them with normal alpha-genotype controls. One hundred twenty-one alpha(+)-thalassemia carriers (-alpha(3.7)/alphaalpha) and 249 controls (alphaalpha/alphaalpha), all of them with normal serum ferritin levels, were subclassified according to age (1-5, 6-10, 11-15, 16-20, and over 20 years old). Reticulocyte analyzes were carried out by flow cytometry and sTfR and s-Epo levels determined by immunonephelometry and chemiluminescence, respectively. The comparisons did not show any significant difference between thalassemics and controls regarding the reticulocyte parameters [percentages and absolute values, P = 0.2643 and 0.5421; high, medium, and low maturation degree, P = 0.2579, 0.2196, and 0.4192; RET maturity index (RMI), P = 0.2471, respectively], as well as the s-Epo levels (P = 0.5711). The sTfR concentrations were higher in the thalassemic group (P = 0.0001), but statistical significance was due only to the 1-5 and over 20 subgroups (P = 0.0082 and 0.0436, respectively). The results found here are compatible with a compensated erythropoiesis and do not confirm the hypothesis mentioned above.

Adolescent↗
PubMed2006

Pulmonary hypertension in thalassemia: association with platelet activation and hypercoagulable state.

The pathogenesis of pulmonary hypertension (PAH), a serious complication in thalassemia, is not well understood. Thromboembolism has been postulated as one of the causative factors; however, there are currently limited specific data on its role. To examine whether increased platelet activation and hypercoagulability are linked to PAH, 25 beta-thalassemia major and beta-thalassemia intermedia patients were evaluated with Doppler echocardiograms for estimation of pulmonary artery pressure and with laboratory assays for indications of a prothrombotic state. The association of clinical variables and abnormal coagulation assays with PAH was determined. PAH was identified in 17 (68%) patients; mean pulmonary artery systolic pressure was 39.8 +/- 5.4 mm Hg. PAH was significantly associated with prior splenectomy, older age, and evidence for chronic hemolysis, diagnosed in both transfused (n = 10) and nontransfused (n = 7) patients. Increased platelet activation, measured by P-selectin, was significantly associated with PAH (P = 0.001). Increased thrombin-antithrombin III level was more prevalent in the presence of PAH, but increased fibrinolysis or low protein C levels were not. This study underscores the role of platelet activation in the development of PAH and stresses its occurrence even among patients who are regularly transfused, especially those who are older and have had splenectomies.

Adolescent↗
PubMed2007

Characterization of a novel deletion causing (deltabeta)0-thalassemia in a Thai family.

A novel deletion of the human beta-globin gene cluster associated with the increased level of fetal hemoglobin (Hb F) in adult life has been demonstrated in a Thai family. A Thai girl who was mistakenly diagnosed as beta-thalassemia/HbE is found to be the compound heterozygote of this mutation and Hb E. The heterozygous father had mild hypochromic and microcytic red blood cells and a high level of Hb F (23.2%). Polymorphic restriction sites in the beta-globin gene cluster identified the homozygous alleles, which localized the deletion region between the psibeta-globin and the 3' beta-globin genes. DNA polymerase that can amplify a long DNA template was employed to examine DNA fragment encompassing this deletion. A 11.3 kilobases (kb) of DNA deletion, beginning approximately 3.1 kb 5' to the delta-globin gene and end in the intron 2 of the beta-globin gene was detected. DNA analysis revealed that this is a case of (deltabeta)(0)-thalassemia with a novel mutation, which can lead to a mild form of beta-thalassemia upon interaction with Hb E.

Adult↗
PubMed1980

Hematological evaluation of patients with various combinations of alpha-thalassemia.

Six patients and their parents from five different families with Hb H have been evaluated clinically and hematologically. Previous studies using restriction endonuclease mapping technique indicated that alpha-thalassemia determinants in these cases are heterogeneous. Only one of the five cases have the usual genotype for Hb H, which is characterized by an alpha-DNA-specific fragment of 20 kb long by Eco RI digestion. Three cases from two different families have Hb H disease with alpha-specific DNA fragments of 22.5 kg/2.6 kg long; and the other two have alpha-specific DNA fragments of 20 kb/2.6 kg long, in Eco RI digestion of the cellular DNA. The hematological examination of the parents suggests that the alpha-thalassemia condition associated with the Eco RI fragment of alpha-specific cellular DNA of approximately 22.5 kb long produces an alpha-thal-2-like clinical condition, while the other alpha-thalassemia determinant associated with a fragment 2.6 kg long results in an alpha-thal-1-like clinical condition. The clinical and hematological findings of the cases with 22.5 kb/2.6 kb fragment patterns were more severe than the case with the 20 kb/2.6 kb combination. This study suggests that variation in the clinical and hematological findings among patients with Hb H disease may well reflect a heterogeneity of the genotype combination.

Adult↗
PubMed1987

Effects of zinc supplementation on linear growth in beta-thalassemia (a new approach).

Linear growth was evaluated in 32 patients with beta-thalassemia major. At the beginning of the study of 40.6% of the patients were below the 10th percentile with biochemical evidence of zinc deficiency. Effects of zinc supplementation on growth velocity (height) were assessed in a controlled manner. Twenty-one children received oral zinc sulphate for a period of 1 to 7 years (15 early- and 6 late-supplemented cases), while the remaining 11 thalassemics were maintained only on conventional transfusion therapy. The mean height velocity of early-zinc supplemented children was significantly greater than that of normal children (P less than 0.01). An increase in height was also observed in the patients who received delayed zinc retardation. The present study demonstrated that zinc deficiency is one of the factors responsible for retarded linear growth in beta-thalassemia major. Only the patients who received zinc supplementation showed an acceleration of growth in height. Administration of zinc could, therefore, be considered as an effective adjuvant therapy in homozygous beta-thalassemia.

Adolescent↗
PubMed1987

Iron status of beta thalassemia carriers.

One hundred twenty-four relatives (aged 17-52 years) of 35 children with severe transfusion-dependent beta thalassemia major were investigated for their beta thalassemia carrier status (determined by Hb-A2 level) and iron status (determined by serum ferritin level). Forty-eight males had beta thalassemia trait (BTT) and 18 males did not have BTT (control); 41 females had BTT and 17 females did not have BTT (control). Serum ferritin levels (mean +/- SEM) of male BTT, male control, female BTT, and female control groups were 151.0 +/- 27.4, 59.6 +/- 16.3, 120.6 +/- 36.6, and 17.2 +/- 6.1 mcg/liter respectively; the differences between the two male and the two female groups were statistically significant (p = .05 and p less than .001). Iron deficiency (serum ferritin below 10.0 mcg/liter) was present in 6.3%, 38.9%, 24.4%, and 58.8% of male BTT, male control Female BTT, and female control groups, respectively; the differences between the two male and two female groups were statistically significant (p less than .01 and p less than .01). Serum ferritin was over 1,000 mcg/liter in four individuals with BTT (2 male and 2 female). Thus, the BTT group had better iron nutrition. This may suggest that the BTT group has an advantage in maintaining iron balance.

Adolescent↗
PubMed1987

Effects of alpha-thalassemia-2 on the developmental changes of hematological values in children with sickle cell disease from Georgia.

The hematology and pathophysiology of sickle cell disease during the postnatal development of younger hemoglobin (Hb) S homozygotes (SS) could be considerably affected by a variability of alpha globin gene numbers. We have documented longitudinal developmental changes of hematological values and hemoglobin composition on 147 patients with SS (alpha alpha/alpha alpha), 64 with SS (-alpha/alpha alpha), and 9 with SS (-alpha/-alpha) between the ages of 1 and 15 years. Non-steady-state data were excluded from these analyses. The number and organization of alpha globin genes was established by gene mapping. As anticipated, mean corpuscular volume and erythrocyte counts correlated with alpha globin gene numbers throughout the 15-year age interval. On the other hand, SS children with alpha alpha/alpha alpha, -alpha/alpha alpha, -alpha/-alpha had similar hemoglobin concentrations up to the ages of 5-10 years. Around the age of 7, the SS patients with -alpha/-alpha developed a higher Hb concentration than that of the SS (-alpha/alpha alpha), which in turn was higher than that of the SS (alpha alpha/alpha alpha). The emergence of this difference coincided with a developmental increase of the mean corpuscular hemoglobin concentration (MCHC) in patients with SS (alpha alpha/alpha alpha) and the decline of Hb F % under 15%. This newly observed developmental change of the MCHC could lead to increased hemolysis and anemia after the age of 5-10 years. It occurs to a smaller extent among SS (-alpha/alpha alpha) or not at all among SS (-alpha/-alpha) such that these two categories of patients have less severe hemolysis and higher hemoglobin levels at older ages. Although the proportion of Hb F was independent of alpha globin gene numbers, the absence of Hb Bart's suggested that alpha-thalassemia promotes the intracellular assembly of Hb F over Hb S tetramers. Thus, the interaction of alpha-thalassemia and Hb F in young SS patients may be more complex than revealed by Hb F levels in cell lysates. Among older SS children (greater than 7 years) alpha-thalassemia and Hb F levels exceeding 15% appear to have additive effects in diminishing the rate of hemolysis.

Adolescent↗
PubMed1987

Application of DNA polymorphisms for prenatal diagnosis of beta thalassemia in Chinese.

Forty-seven Chinese suffering from beta thalassemia major and their parents were studied to establish linkage of the beta thal and beta A genes with 11 restriction site polymorphisms. There is marked linkage disequilibrium at the BamH I site 3' to the beta globin gene, such that, in 31% of pregnancies, absence of the site in the fetus can exclude beta thalassemia major. Using four restriction sites (Hinc II psi beta, Ava II beta, Hind III beta, and BamH I beta), prenatal diagnosis is feasible in all families. In 46% of all cases, a definitive diagnosis can be made, and in the remaining cases, a 50% chance of exclusion is possible. Fetal blood globin chain analysis would be required for the failures. Our experience in nine successive beta thalassemia prenatal diagnosis is also reported.

China↗
PubMed1987

Association in cis of beta +-thalassemia and hemoglobin S.

A Moroccan woman was investigated because of a typical beta-thalassemia trait associated with a low-percentage (11%) hemoglobin (Hb) variant. The beta-thalassemia trait was manifested by a microcytosis, a high HbA2 (above 6%), and an increase of the alpha/beta biosynthetic ratio (1.31). The variant was identified to HbS by amino acid analysis of the abnormal peptide (beta T1) and by DNA mapping with Sau I (Mst II) restriction endonuclease. No additional amino acid substitution was recorded in the beta s-chain. The reduction of beta-globin synthesis occurred exclusively at the expense of the beta s-chain. These results are consistent with the existence of a beta s mutation and a beta +-thalassemia in cis.

Adult↗
PubMed1988

Restriction fragment length polymorphism in the interzeta hypervariable region for prenatal diagnosis of non-deletion alpha thalassemia.

A Bam HI restriction fragment length polymorphism in the interzeta hypervariable region (IZ HVR) of the zeta-alpha gene cluster was used for the prenatal diagnosis of a pregnancy at risk for Hb H hydrops fetalis. The parents had zeta-alpha thalassemia 1 and non-deletion alpha thalassemia, respectively, and a previous hydrops was missed using the conventional method of gene detection. In this prenatal diagnosis, linkage to IZ HVR was used to exclude non-deletion alpha thalassemia, and the numbers of zeta and alpha genes in the fetus were quantitated to predict the exact genotype. Confirmation was made by analysis of cord blood at delivery.

Amniocentesis↗
PubMed1992

Pseudoxanthoma elasticum-like skin lesions and angioid streaks in beta-thalassemia.

One hundred patients with homozygous or doubly heterozygous beta-thalassemia (62 with the major form and 38 with beta-thalassemia intermedia) were examined for signs of Pseudoxanthoma elasticum (PXE). Diagnostic skin lesions were found in 16 patients with either form of the basic disease. Twenty percent of all patients had angioid streaks (AS); both PXE skin lesions and AS were found in 10% of the patients; in all, 26% had either one or both of these manifestations. A positive correlation was found between the presence of one or both types of lesion and age of the patients (P = 0.032); there were no differences as regards ferritin and hematocrit levels, number of transfused units, chelation therapy, and splenic status between patients with PXE/AS findings and those without. The pathogenesis of these connective tissue manifestations at such a high frequency in beta-thalassemia is not clear; the possibilities of it's being acquired or inherited are discussed, the former being considered to be the more economical interpretation.

Adolescent↗
PubMed1993

Characterization of nondeletion alpha-thalassemia mutations in the Greek population.

alpha-Thalassemia is usually due to deletions within the alpha-globin gene cluster, leading to loss of function of one (-alpha) or both [-(alpha) or --] alpha-globin genes. Nondeletion mutations (denoted alpha alpha T or alpha T alpha) are less frequent and in Greece are not well defined. We report the analysis of 16 nondeletion alpha-thalassemia chromosomes using a polymerase chain reaction method to amplify specifically the alpha 2-globin gene, which was subsequently screened using ASO hybridization or restriction enzyme analysis for four mutations already characterized in other Mediterranean and Middle Eastern populations. Of the 16 nondeletion chromosomes, nine had the polyadenylation signal mutation (alpha PolyA alpha), two the IVSI 5' pentanucleotide deletion (alpha Hph alpha), two the Hb Icaria mutation (alpha Ic alpha), and one the initiation codon mutation (alpha Nco alpha). In two, the defects are still undefined. These findings show that nondeletion alpha-thalassemia in Greece is heterogeneous and that the most frequent mutation (accounting for > 50%) is the polyadenylation signal mutation, which to date was most commonly found in the Saudi Arabian population.

Alleles↗
PubMed1994

Quantities of alpha Q chain variants in heterozygotes with and without a concomitant beta-thalassemia trait.

We have analyzed the quantities of alpha x chain-containing hemoglobins (alpha 2 x beta 2 and alpha 2 x delta 2) in 14 heterozygotes for Hb Q-India [alpha 64(E13)Asp-->His] or Hb Q-Thailand [alpha 74(EF3)Asp-->His]; both amino acid replacements are the result of mutations in the alpha 1-globin gene. Five of these persons (three with Hb Q-India and two with Hb Q-Thailand) had an additional beta(0)-thalassemia heterozygosity. The average quantities for Hb Q + Hb Q2 in the four groups were 17.2% (alpha alpha Q/alpha alpha; beta A/beta A), 9.5% (alpha alpha Q/alpha alpha; beta A/beta(0) Th), 26.8% (-alpha Q/alpha alpha; beta A/beta A), and 16.95% (-alpha Q/alpha alpha; beta A/beta(0) Th). These variations can best be explained by a posttranslational control mechanism; an imbalance in the alpha A, alpha Q, and beta A chain ratio will favor the alpha 2 Q beta 2 formation when an alpha-thalassemia is present and will reduce its formation in the presence of a beta-thalassemia heterozygosity.

Adolescent↗
PubMedDate not supplied

Beta-globin cluster haplotypes in normal individuals and beta(0)39-thalassemia carriers from Sardinia, Italy.

Seven polymorphic sites in the beta-globin cluster in association with specific thalassemia mutations were analyzed in a sample from Sardinia, Italy. In order to verify previous works carried out on normal samples (beta(A)/beta(A)) and family studies on beta-thalassemia homozygotes individuals, the haplotype frequencies in both normal individuals (beta(A)/beta(A)) and beta(0)39-thalassemia carriers (beta(A)/beta0) were studied. In our work chromosomes carrying beta(0)39 mutation are characterized by a prevalence of haplotype II (- + + - + + +) (52%) relative to haplotype I (+- - - - + +) (29%), in contrast, among chromosomes with beta(A) the frequency of haplotype I is much greater than that of haplotype II. These data confirm what was found by other authors. Nevertheless, our results disagree with those of previous studies of Sardinians, both in frequencies values and in the numbers of haplotypes identified. Population analysis performed with samples carrying the beta-thalassemic mutation highlighted the peculiarity of Sardinians with respect to other Mediterranean populations. The Corsican population is most similar to the Sardinian population, confirming previous analyses performed with both classical markers and mitochondrial and genomic DNA.

Adult↗
PubMed1995

Clinical and hematologic aspects of the X-linked alpha-thalassemia/mental retardation syndrome (ATR-X).

The hallmarks of the X-linked alpha-thalassemia/mental retardation (ATR-X) syndrome are severe psychomotor retardation, minor facial anomalies, genital abnormalities, and an unusual form of alpha-thalassemia. The demonstration of HbH inclusions in red blood cells after incubation with brilliant cresyl blue confirms the diagnosis. We describe 15 previously unreported cases and analyse the phenotypic and hematologic findings in these subjects and compare them with previously published cases. This study demonstrates the consistency of the main characteristics of this syndrome and extends the phenotype. Developmental changes in phenotype, in particular the coarsening of the facial appearance, are illustrated. The hematologic findings are shown to vary widely; in some cases the manifestation of alpha-thalassemia may be subtle and missed without repeated examination.

Abnormalities, Multiple↗
PubMed2007

HbVar database of human hemoglobin variants and thalassemia mutations: 2007 update.

HbVar (http://globin.bx.psu.edu/hbvar) is a locus-specific database (LSDB) developed in 2001 by a multi-center academic effort to provide timely information on the genomic sequence changes leading to hemoglobin variants and all types of thalassemia and hemoglobinopathies. Database records include extensive phenotypic descriptions, biochemical and hematological effects, associated pathology, and ethnic occurrence, accompanied by mutation frequencies and references. In addition to the regular updates to entries, we report significant advances and updates, which can be useful not only for HbVar users but also for other LSDB development and curation in general. The query page provides more functionality but in a simpler, more user-friendly format and known single nucleotide polymorphisms in the human alpha- and beta-globin loci are provided automatically. Population-specific beta-thalassemia mutation frequencies for 31 population groups have been added and/or modified and the previously reported delta- and alpha-thalassemia mutation frequency data from 10 population groups have also been incorporated. In addition, an independent flat-file database, named XPRbase (http://www.goldenhelix.org/xprbase), has been developed and linked to the main HbVar web page to provide a succinct listing of 51 experimental protocols available for globin gene mutation screening. These updates significantly augment the database profile and quality of information provided, which should increase the already high impact of the HbVar database, while its combination with the UCSC powerful genome browser and the ITHANET web portal paves the way for drawing connections of clinical importance, that is from genome to function to phenotype.

DNA Mutational Analysis↗