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PubMed1999

Standardization on laboratory diagnosis of thalassemia and abnormal hemoglobin.

Thalassemia is one of the most common single gene disorders. The geographic distribution of thalassemia and abnormal hemoglobin has been known for many years. A worldwide significant spread of these abnormal genes, especially from Southeast Asia, occurred in the last two decades. This has resulted in a dramatic increase of Hb E disorders and various Southeast Asian thalassemia genotypes, which means that requests for hemoglobinopathy investigations are likely to increase in many laboratories worldwide. Hemoglobinopathy screening and diagnosis may need to be undertaken antenatally, neonatally and in certain hematological situations. The introduction of automation for hemoglobinopathy screening, including the automated cell counting and HPLC system, is an important advance in technology for hematology laboratories. The instruments need to be calibrated and standardized to get an accurate data for interpretation. Internal and external control samples are also needed. Combination of test results is usually required to achieve a proper diagnosis, which in turn, provide a self-check for each laboratory test.

Adult↗
PubMed1999

Serum erythropoietin levels in thalassemia major and intermedia.

Serum erythropoietin (EPO) levels were determined by enzyme linked immunosorbent assay (ELISA) in 61 thalassemic patients, consisting of 23 thalassemia major (TM) patients with multiple transfusion, 38 patients with thalassemia intermedia (TI). Thirty-two normal controls were also studied. The mean serum EPO levels were significantly higher in both groups with TM (165.96 +/- 17.31 mlU/ml) and TI (126.43 +/- 50.56 mlU/ml) compared with the control group (8.33 +/- 3.91 mlU/ml). The mean value of hematocrit (Hct) in the patients with TM (18.70 +/- 3.51%) was lower than those with TI (25.24 +/- 4.19 %) whereas the mean serum EPO level were significantly higher in TM than TI patients. An inverse correlation between the serum values of EPO and Hct was observed in both TI and TM patients, however this correlation was significant only in TI (r = -0.61, p<0.001). These data showed that serum EPO levels increased in all thalassemia patients despite repeated transfusion. Multiple transfusion may modulate the response of serum EPO to the degree of anemia, resulting in increased EPO levels and independent anemia in the TM patients.

Adolescent↗
PubMedDate not supplied

[Molecular analysis and prenatal diagnosis of beta-thalassemia: about our experience in central Tunisia].

Beta-thalassemia, by its high frequency and its heterogeneity, constitutes a real problem of health in Tunisia. Prenatal diagnosis by DNA analysis represents the only reality for couples at risk. The denaturant gradient (urea and formamide) on polyacrylamide gel electrophoresis has been performed in our laboratory, using psoralen as chemical clamps. This method is simple, reliable, safe, rapid, without radioactivity and has a reasonable cost (chemical clamps). Even if it needs an informatic modelization in other laboratories, this method seems to be adapted to our economic and work conditions and to the molecular heterogeneity of the Tunisian beta-thalassemia. We present the results of an epidemiological molecular study on 75 patients with beta-thalassemia and the results of ten prenatal diagnosis. The molecular lesions codon 39 (C-T) and IVS1 nt2 (T-G) are the most frequent in our study. This technical approach provides genetic counselling for at risk families by offering prenatal diagnosis (reducing as possible the cost and the delay of the result) after prealable family study and identification of the mutation(s).

Codon↗
PubMed2001

TT virus infection in adult beta-thalassemia major patients.

BACKGROUND AND OBJECTIVES: Patients with thalassemia-major are at risk of blood-borne viral infections. TT virus (TTV), a single stranded, circular DNA virus, has recently been found to be associated with acute and chronic hepatitis. The aims of this study were to assess the prevalence of TTV infection in adult patients with transfusion-dependent thalassemia, and to evaluate the clinical significance of TTV. DESIGN AND METHODS: We studied 68 adult patients with thalassemia major, 97% of whom were hepatitis C virus (HCV) antibody positive. TTV DNA was amplified from serum by heminested polymerase chain reaction (PCR). Direct sequencing of PCR products was used to establish TTV genotypes. RESULTS: TTV DNA was detected in 47 patients (69.1%). Sequence analysis of PCR products identified TTV genotype 1b as the most common viral genotype in this group. Patients co-infected by HCV and TTV had a significantly higher histologic grade score than patients with isolated HCV infection (5.1+/-2.7 vs. 2.8+/-1.7, p=0.02) while the stage score was not significantly different. INTERPRETATION AND CONCLUSIONS: TTV is highly prevalent among Italian multiply transfused patients. In these patients TTV viremia appears to affect the necro-inflammatory activity of hepatitis C, though no evidence of an effect on the evolution of fibrosis was found.

Adult↗
PubMed1998

[Association of HLA-DQB1 alleles and the susceptibility to beta-thalassemia in Guangxi Chinese Zhuang nationality].

OBJECTIVE: To investigate the relationship between HLA-DQB1 allele and susceptibility to beta-thalassemia in Guangxi Chinese Zhuang nationality. METHODS: The polymorphism of the HLA-DQB1 loci in 64 randomly selected, unrelated Guangxi Zhuang individuals with beta-thalassemia was investigated by PCR-SSP. RESULTS: Compared with normal controls, the frequency of HLA-DQB1*0604 allele was significantly increased in the patient group, with a relative risk(RR) of 9.9(chi 2 = 20.78, P < 0.005), while the frequencies of other HLA-DQB1 alleles did not in the patient group. CONCLUSION: The susceptibility to beta-thalassemia in the Guangxi Zhuang individuals is associated with HLA-DQB1*0604 allele.

Adult↗
PubMed2001

The possible role of autoimmunity in the pathogenesis of diabetes in B-thalassemia major.

OBJECTIVE: To evaluate the possible role of autoimmunity in the pathogenesis of diabetes associated with B-thalassemia, we studied a cohort of 53 B-thalassemic individuals, under long term blood transfusion, that included twelve patients with diabetes (22.6%). MATERIAL AND METHODS: To evaluate the activation of an autoimmune response, individuals were tested for islet cell antibodies (ICA), glutamic acid decarboxylase (GAD) autoantibodies, insulin autoantibodies (IAA) and serum anti-nuclear antibodies (ANA). RESULTS: Nine of the total B-thalassemic population (16.98%) were ICA-positive. The frequency of ICA-positive subjects among thalassemic individuals was higher than in the general population. Five (41.6%) of the ICA-positive individuals were diabetic. Of these, three were serum C-peptide-negative (<0.21 nmol/l). HLA class II typing of our thalassemic population did not reveal significantly different allelic frequencies with respect to the control population. CONCLUSIONS: Our study demonstrates evidence of immune system activation against pancreatic B-cells in B-thalassemia and we propose that iron deposition may, through oxidative damage, act as an environmental factor that triggers the autoimmune response. Therefore, we speculate that pancreatic autoimmunity may contribute to selective B-cells damage in the pathogenesis of diabetes associated with B-thalassemia.

Adult↗
PubMed2000

[Evaluation of red cell mean corpuscular volume and simple tube red cell osmotic fragility quantitative test in detection of thalassemia].

OBJECTIVE: To evaluate and compare the detection efficiency of red cell mean corpuscular volume(MCV) test against simple tube red cell osmotic fragility quantitative test(STROFQT) in diagnosis of thalassemia. METHODS: 1978 subjects (989 couples) were detected by both MCV test and STROFQT, 158 samples from subjects were tested by alpha,beta-thalassemia DNA polymerase chain reaction(PCR) and serum ferritin test. RESULTS: The positive rate (9.0%), sensitivity (98.9%) of MCV test were higher than those of STROFQT (8.1%, 88.6%) (P < 0.05). The specificity of MCV test showed no statistic significance compared with that of STROFQT (P > 0.05). CONCLUSION: Both MCV test and STROFQT served as helpful approaches in detection of thalassemia, MCV test shows better diagnostic efficiency for screening than STROFQT.

Adult↗
PubMed1975

The measurement of free erythrocyte porphyrin (FEP) as a simple means of distinguishing iron deficiency from beta-thalassemia trait in subjects with microcytosis.

Assay of free erythrocyte porphyrin (FEP) and measurement of red cell indices were obtained in a group of subjects with iron deficiency and beta-thalassemia trait to determine if these studies cound detect these disorders and discriminate bbetween them. FEP values were increased in 90.2 per cent of subjects with iron deficiency but were within the normal range in 96.6 per cent of subjects with beta-thalassemia trait. Mean FEP values increased sligtly as transferrin saturation fell but became abnormally elevated when the transferrin saturation fell but became abnormally elevated when the transferrin saturation was less than 15 per cent. Unlike subjecs with iron deficiency in whom the mean corpuscular volume varied from 46 to 84, all individuals with beta-thalassermia trait exhibited microcytosis. In most instances, determination of FEP appears to distinguish beta-thalassemia trait from iron deficiency in patients with microcytosis.

Anemia, Hypochromic↗
PubMed1999

[Analysis of prenatal diagnosis for 120 cases of beta-thalassemia].

OBJECTIVE: To analyse the results of prenatal gene diagnosis of beta-thalassemia. METHODS: By using the reverse dot blot method with an allele specific oligonucleotide probe(ASO/DRB). RESULTS: In 120 cases of prenatal gene diagnosis, there are 30 of normal fetal; 63 of beta-thalassemia heterozygotes; 26 of beta-thalassemia homozygotes or dual heterozygotes; one of no diagnosis because the beta mutated gene can not be detected in one side of the parent. CONCLUSIONS: Acording to the follow-up studies, the babies unconcordance with prenatal diagnosis have not been found, the accuracy rate being 100%. Amniotic fluid specimen of the middle stage of pregnancy is the best for detection.

Amniocentesis↗
PubMed2001

Prenatal diagnosis of der(11)t(11;18)(q24;q21.3) due to paternal balanced translocation and both parents are carriers of alpha-thalassemia-1--a case report.

A couple were identified as alpha-thalassemia-1 carriers (father: alpha-thal-1 of Filipino type, mother: alpha-thal-1 of SEA type). Amniocentesis was done at 19 weeks of gestation by a local obstetrician. Molecular study of amniotic fluid presented a non-thalassemia fetus, but the cytogenetic study revealed a karyotype of 46,XX,der(11)t(11;18)(q24;q21.3), resulting from a paternal balanced reciprocal translocation and unbalanced adjacent 1 segregation. The pregnancy was terminated at 23 weeks of gestation. The gross of fetus revealed bilateral cleft lip and palate, hypertelorism, flat nasal bridge, frontal bossing, micrognathia, low set ears, short neck with cystic hygroma, overlapping fingers, prominent heels, and limited hip abduction. The chromosome complement of the present case was partial monosomy for 11q24-qter and partial trisomy for 18q21.3-qter. This is the first prenatal diagnosis of unbalanced translocation with der(11)t(11;18)(q24;q21.3) pat due to paternal balanced translocation and both parents being carriers of alpha-thalassemia-1.

Adult↗
PubMedDate not supplied

Thalassemias and their dental implications.

Thalassemias constitute a form of anemia that pose clear problems in relation to dental treatment. Dental professionals must be aware of the treatment adaptations required in patients with severe forms of beta-thalassemia. Until medical research is able to afford a definitive solution to these diseases (thereby greatly simplifying the dental management of such patients), effort will continue to center on the improvement of available therapeutic modalities, with the aim of obtaining effective and inexpensive oral chelators and drugs that either individually or in combination allow increases in fetal hemoglobin levels. Undoubtedly, the use of such measures together with serial blood transfusions has made it possible for an ever increasing number of patients with beta-thalassemia to reach adult age, where the provision of integral rather than merely palliative dental treatment must be seriously considered. At present, the clinical orofacial manifestations caused by the erythroid mass expanding the facial bones - resulting in dental malocclusions and protrusions tend to be less intense as a result of early medical treatment. In the future, gene therapy may be expected to allow a normal facial appearance thanks to complete healing of the patient.

Chelating Agents↗
PubMed2002

Enhanced macrophagic attack on beta-thalassemia major erythroid precursors.

BACKGROUND AND OBJECTIVES: In beta-thalassemia major (Cooley's anemia), ferrokinetic studies show that 60-80% of erythroid precursors die in the marrow or extramedullary sites. However, study of marrow aspirates does not reveal huge numbers of dead and dying erythroid precursors. We explored this apparent discrepancy with the hypothesis that enhanced phagocytosis of thalassemic erythroid precursors was a likely explanation. Prior studies had reported on an increase in thalassemic marrow macrophages and their enhanced state of activation. Therefore this study explored the characteristics of thalassemic erythroid precursors which might lead to enhanced susceptibility to phagocytosis. We have shown that enhanced erythroid apoptosis parallels the extent of ineffective erythropoeisis in thalassemic patients, and apoptotic cells are rapidly phagocytosed. Thus, increased apoptosis and perhaps other features of thalassemic erythroid precursors might be the cause of their enhanced phagocytic removal. DESIGN AND METHODS: Erythroid precursors were isolated from normal and beta-thalassemia major marrow, and incubated with uniform cultures of murine macrophages. The extent of phagocytosis was measured and then specific inhibitors were added to identify some of the messages effete erythroid precursors use to signal their condition to macrophages. RESULTS: Beta-thalassemia major erythroid precursors are phagocytosed twice as effectively as normal erythroid precursors. INTERPRETATION AND CONCLUSIONS: Experiments using inhibitors of phagocytosis showed that enhanced apoptosis is certainly responsible for part of the increased phagocytosis of thalassemic erythroid precursors. Interestingly, normal erythroid precursors are also subject to phagocytosis by qualitatively similar mechanisms.

Animals↗
PubMedDate not supplied

Complete heart block in thalassemia major: a case report.

Cardiac complications of iron overload are the most common cause of death in patients with thalassemia major. These complications include recurrent pericarditis, refractory congestive heart failure and rhythm disorders. The usual rhythm disturbances are supraventricular or ventricular premature contractions and first-or second-degree heart block. Complete heart block is a very rare complication of thalassemia major. Herein, we report a case of complete heart block with thalassemia major. The patient also had serious congestive heart failure. Management of the heart block with pacemaker brought no clinical improvement, and she died in the second month of hospitalization.

Adolescent↗
PubMed2002

Unrelated bone marrow transplantation in thalassemia. The experience of the Italian Bone Marrow Transplant Group (GITMO).

BACKGROUND AND OBJECTIVES: Allogeneic bone marrow transplantation (BMT) is a widely accepted therapeutic approach in homozygous beta-thalassemia. However, the majority of patients do not have a genotypically identical donor within the family. This prompted us to conduct a pilot study to investigate the feasibility of matched unrelated bone marrow transplantation in thalassemia. The major drawback was the high risk of immunologic and transplant-related complications, mainly graft-versus-host disease (GvHD) and graft failure. DESIGN AND METHODS: Our aim was to reduce this risk through careful selection of donor/recipient pairs. HLA haplotypes that show a high linkage disequilibrium among their class I, class II and class III alleles are considered extended or ancestral haplotypes. RESULTS: These haplotypes are conserved and can be shared by apparently unrelated individuals. Our study shows that matching for these haplotypes significantly improves the outcome of unrelated bone marrow transplantation in thalassemia. In fact, results were comparable to those obtained in transplants using HLA-identifical family donors. INTERPRETATION AND CONCLUSIONS: Better results were obtained in patients with lesser iron overload and when the donor shared an identity for the DPB1 alleles.

Adolescent↗
PubMed2002

[The prevention programs for beta thalassemia in the Jezreel and Eiron valleys: results of fifteen years experience].

UNLABELLED: beta thalassemia is an hereditary disease caused by mutations in the beta globin gene. The clinical course is characterized by chronic hemolytic anemia that required regular blood transfusions. Secondary to the blood transfusions, patients developed severe hemosiderosis that can cause death in the early twenties unless appropriate iron chelator therapy is given. Due to the severity of the disease and the expensive treatment, a prevention program should be instituted. We report our experience in a prevention program among pregnant women in the Jezreel and Eiron Valleys during a period of fifteen years. RESULTS: A total of women were screened for beta thalassemia. Within this group, 928 were found to be carriers and 180 couples were found to be at risk to deliver an affected baby. Two hundred and fifty nine prenatal diagnoses were performed and in 45 cases the parents decided to abort the affected child. In ten cases the parents choose to deliver an affected baby. Fifteen different beta globin mutations were detected in the area covered by the program. CONCLUSIONS: A prevention program among pregnant women is feasible and prevents most of the new cases of hemoglobinopathies in the covered area. RECOMMENDATIONS: Based on our experience, and the relative low cost of this program, we recommend instituting a national prevention program for beta thalassemia throughout the country.

Abortion, Induced↗
PubMed2002

[Serum levels of erythropoietin and transferrin receptor in thalassemia of the Li nationality].

immunosorbent To determine serum EPO and soluble transferrin receptor (sTfR) level and to assess the degree of erythropoietic proliferation in patients with thalassemia of Li nationality, 50 cases and 50 normal individuals were studied. Enzyme-linked immunosorbent assay was used for EPO and sTfR. Results showed that serum EPO and sTfR levels in beta-thalasemia major patients were significantly higher than those in normal control group, and no significant difference in beta-thalassemia minor cases with those in control. It is concluded that increase of serum EPO and sTfR level is related to the type of thalassemia.

Adolescent↗
PubMed2002

[Association of the relationship between HLA-DQB1 alleles and major beta-thalassemia in 42 guangdong Chinese].

To investigate the relationship between HLA-DQB1* alleles and major beta-thalassemia, the HLA-DQB1* loci typing was performed with polymerase chain reaction-sequence specific primer (PCR-SSP) in 42 unrelated (unconsanguineous) patients with major beta-thalassemia and 45 normal control individuals in Guangdong Province. Results showed that the frequency of HLA-DQB1*06 allele in patient group (19.0%) was higher than that in the control group (4.4%) kappa(2) = 8.961, p < 0.01). Our data suggests that HLA-DQB1*06 allele is associated with pathogenesis of the major beta-thalassemia in Guangdong area.

Alleles↗
PubMed2003

Unrelated bone marrow transplantation for beta-thalassemia major: report of the first 2 successful cases in Asia.

We report our experience in successful unrelated-donor bone marrow transplantation in 2 cases of beta-thalassemia major, which are approved to be the first 2 cases in Asia. The 2 children receiving transplantation of the bone marrow from unrelated donors were diagnosed as having beta-thalassemia major, whose gene mutation type was homozygous and double heterozygote. High-resolution HLA typing found a mismatch with 1 sub-locus in both cases, and red blood cell type was mismatched in 1 case. Pretransplant conditioning protocol contained busulfan (BU, 16 mg/kg x b.w.), cyclosphamide (CY, 200 mg/kg x b.w.), anti-thymocyte globulin (ATG, 90 mg/kg x b.w.) and fludarabine (25 mg x d-1 x m-2). To prevent graft-versus-host disease (GVHD) episodes, cyclosporine-A (Cs-A) and methotrexate (MTX) were administered. The 2 cases experienced condition resembling serum sickness during pretransplant conditioning. After bone marrow transplantation, 1 case had grade acute GVHD in the skin, another developed grade acute GVHD in both the skin and intestinal tract, but the condition was brought under control in both cases after proper treatment. The time for peripheral neutrophil granulocyte recovery to above 0.5 x 10(9)/L was 19 and 16 days postoperatively, respectively, and the time of WBC recovery to normal was 54 and 80 days postoperatively. Platelet recovery to over 50 x 10(9)/L occurred on postoperative days 61 and 90, and Hb recovered to above 100 g/L in both case on days 110 and 83 respectively. The time of final blood transfusion was 53 and 62 days postoperatively for the 2 patients. Gene mutation type in the 2 cases was switched to normal of the donors. After retrieval of relative literature, the 2 cases were approved as the first 2 successful unrelated-donor bone marrow transplantation cases in Asia. This will provide a new possibility of donor supply for hematopoietic stem cells transplantation in thalassemia.

Adult↗