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Hepatitis E virus infection in patients from Saudi Arabia with sickle cell anaemia and beta-thalassemia major: possible transmission by blood transfusion.

The seroprevalence of antibodies against hepatitis E virus (HEV) and hepatitis C virus (HCV) was investigated in Saudi children with sickle cell anaemia (SCA) (50 patients: 28 boys, 22 girls; age range 2-14 years) and beta-thalassemia major (28 patients: 12 boys, 16 girls; age range 2-12 years). The SCA patients were from the Gizan area (South) while the thalassemics were from the Riyadh area (Central province). The prevalence of hepatitis E virus antibody (HEVAb) in patients with SCA (18.0%) and in those with beta-thalassemia major (10.7%) was higher than in the control groups (5.5% and 2.8%) but this did not reach the level of statistical significance. In contrast to the situation with HEV, hepatitis C virus antibody (HCVAb) positivity was significantly higher in patients with SCA (16.0%) and in thalassemics (57.1%) than in the respective control groups. Although the difference in HEV seropositivity between beta-thalassemia major, SCA patients and their respective controls is not statistically significant, the possibility of blood-borne HEV in the Saudi population cannot be excluded. Further investigations using HEV-specific polymerase chain reaction techniques are required to confirm whether transmission of HEV through blood preparations or transfusion is possible.

Adolescent↗

Control of homozygous beta-thalassemia by carrier screening and antenatal diagnosis in Sardinians.

This paper reports the present results of an ongoing program aimed at preventing homozygous beta-thalassemia by means of heterozygote screening and antenatal diagnosis in the Sardinian population. Screening based on the knowledge of carrier frequency and types of thalassemia prevalent in this population was designed to discover all heterozygotes except the few silent beta-thalassemia carriers. Most of the couples at risk were informed and accepted testing. Information was conveyed by mass media, midwives and marriage registry offices. Antenatal diagnosis was accepted by the majority of the couples counselled. The results of antenatal testing were very accurate. There was only one misdiagnosis out of 949 pregnancies tested. This risk of fetal loss was 7.5%. The program was highly effective, as shown by the decline of the incidence of the homozygous state from 1:205 live births in 1976 to 1:557 in 1981.

DNA↗

A case of X-linked alpha-thalassemia/mental retardation syndrome: analysis of hemoglobin by an automated glycated hemoglobin analyzer.

A 5-year-old male patient with X-linked alpha-thalassemia/mental retardation syndrome is reported. He showed multiple minor anomalies including characteristic facial abnormalities, alpha-thalassemia, severe mental retardation, and hypogonadism. Analysis of his hemoglobin by high performance liquid chromatography using an automated glycated hemoglobin analyzer revealed an abnormal peak. Identification of an abnormal peak by an automated glycated hemoglobin analyzer will aid in the diagnosis of patients with X-linked alpha-thalassemia/mental retardation syndrome.

Abnormalities, Multiple↗

Platelet alloimmunization after long-term red cell transfusion in transfusion-dependent thalassemia patients.

BACKGROUND: The platelet (PLT) alloimminization status after long-term red cell (RBC) transfusion in thalassemia patients was investigated, including antibodies against HLA antigens and PLT-specific glycoprotein antigens. STUDY DESIGN AND METHODS: Blood samples from a total of 60 thalassemia patients who routinely received washed RBCs were tested for the presence of HLA antibodies and PLT-specific glycoprotein antibodies with a commercial enzyme immunoassay kit. All patients were rescreened at a follow-up period of 12 to 15 months. RESULTS: At the first year of study, 19 (31%) patients had HLA antibodies, 13 (22%) had HLA antibodies and PLT-specific antibodies, and 1 (2%) had PLT-specific antibodies. One patient showed weak reactive PLT autoantibody. The follow-up study showed that 7 patients developed HLA antibodies, whereas 1 patient lost HLA antibody activity. Nine patients developed new PLT-specific antibodies, yet 12 patients lost at least one of their PLT-specific antibodies. CONCLUSION: Long-term RBC transfusions can induce PLT alloimmunization, both to HLA antigens and to PLT-specific antigens. The residual PLTs and white blood cells in RBC components could be the sources of immunization. In our thalassemia patients, HLA antibodies likely sustain longer than PLT-specific antibodies.

Adolescent↗

Prenatal diagnosis of thalassemia and hemoglobinopathies in Switzerland.

During a 10-month period, 10 couples originating from Africa (3), the tropics (1) and the thalassemia-belt region (6), living in Switzerland, requested prenatal diagnosis of hemoglobinopathies. Hb SS (twice), Hb Bart's (Hydrops fetalis) and beta-thalassemia major were diagnosed either by gene mapping or by direct detection of the mutations in DNA amplified by the PCR procedure. Whenever it was possible to obtain fetal blood or tissue, diagnosis was confirmed. In one Vietnamese man, concomitant existence of alpha-thal 1 with beta-thalassemia resulted in an unusually high Hb level because of balanced alpha and beta globin synthesis. The 10 couples examined originated from 7 different countries and presented at least 7 different Hb pathologies. This variety of pathologies represents the main difficulty for prenatal diagnosis of hemoglobinopathies in a non-endemic country. A diagnostic approach to overcome this problem is developed.

Base Sequence↗

Correlation between soluble transferrin receptor and serum ferritin levels following bone marrow transplantation for thalassemia.

This study analyzes the serum transferrin receptor (sTfR) levels in a series of 230 ex-thalassemics with a follow-up of 1 to 9 years after bone marrow transplantation (BMT) for homozygous beta thalassemia. Ex-thalassemics are individuals, cured of homozygous beta thalassemia by BMT, who maintain different degrees of iron overload acquired during the pretransplant period. Both in experimental and clinical conditions, sTfR concentrations have been shown to be a quantitative measure of body iron status. This study was carried out to assess whether the level of sTfR may be of help in determining the extent of iron overload in ex-thalassemics. Patients who received the marrow from their HLA-identical sibling donor heterozygous for beta thalassemia, namely heterozygous ex-thalassemics, displayed significantly higher levels of sTfR than patients transplanted from their normal sibling donors (normal ex-thalassemics). This finding suggests that increased erythropoiesis, albeit in part ineffective in heterozygous ex-thalassemics, is responsible for the sTfR increment. Both heterozygous and normal ex-thalassemics had significant lower sTfR levels than their heterozygous (p < 0.003) or normal (p < 0.0001) donors, respectively. These differences may be ascribed to the presence of iron overload in ex-thalassemics in comparison to their normal or heterozygous donors who did not present excess of iron in the body. A significant inverse correlation between sTfR and serum ferritin levels (r = -0.54, p < 0.0001) was found when normal ex-thalassemics were considered. In heterozygous ex-thalassemics, the lack of correlation between these two parameters may be explained by the enhanced erythropoietic activity of individuals with thalassemic trait. These results suggest that the level of sTfR may be a useful indicator of iron overload in normal ex-thalassemics.

Adolescent↗

Rupture of chordae tendineae in patients with beta-thalassemia.

Cardiac disease is the primary cause of mortality in beta-thalassemia patients. Except for ventricular dysfunction and pulmonary hypertension that represent the main forms of heart disease in these patients, valvular abnormalities including valvular regurgitation, endocardial thickening and calcification and mitral valve prolapse have also been described. Here we present two patients with thalassemia major and mitral chordal rupture, a previously undescribed abnormality in this population. Pathogenesis of this finding may involve thalassemia-related pseudoxanthoma elasticum-like syndrome, a diffuse elastic tissue defect, which is observed with a notable frequency in these patients and has been associated with numerous cardiovascular complications, including valvular ones.

Adult↗

Cardiac status in well-treated patients with thalassemia major.

OBJECTIVE: To assess cardiac status in a large group of patients with thalassemia major who had been treated in a standard way since their early infancy with intensive transfusions and deferoxamine chelation therapy and who had good compliance with this regimen. METHODS AND RESULTS: We assessed clinically and echocardiographically 202 thalassemia major patients aged 27.3 +/- 6.3 yr and 75 age and sex-matched healthy controls. Overt cardiac disease was encountered in 14 patients (6.9%), including 5 (2.5%) with congestive heart failure, aged 26-37 yr, and 9 with systolic left ventricular (LV) dysfunction, aged 23-37 yr. Ten patients (5.0%) had a history of pericarditis. Left atrial and LV diameters, LV mass and cardiac output were significantly higher in patients than in controls, while peripheral resistance and LV afterload were significantly lower. Relative LV wall thickness did not differ between patients and controls, but it was significantly lower in patients with overt cardiac disease compared to those without (P < 0.05). Restrictive LV filling was observed in 37.6% of patients and was significantly more frequent in cases with overt cardiac disease (P < 0.01). Pulmonary hypertension was practically absent. Hematological parameters and pulmonary artery pressure levels were not independently associated with the presence of overt cardiac disease. CONCLUSION: Strict lifelong adherence to the standard transfusion and deferoxamine therapy reduces considerably the occurrence of heart failure, LV dysfunction and pericarditis, prevents early heart failure and pulmonary hypertension, but does not eliminate completely cardiac disease in patients with thalassemia major.

Adolescent↗

Serum ferritin level as a predictor of impaired growth and puberty in thalassemia major patients.

OBJECTIVE: Previous studies suggested that in patients with thalassemia major, initiating deferoxamine (DFO) therapy before puberty can prevent iron-induced failure of growth and puberty. However, early initiation of chelation has also been associated with DFO toxicity. The aim of this retrospective study was to determine the prevalence rates of endocrine complications and DFO bone toxicity in our thalassemia major patients and to correlate them with the degree of iron chelation. METHODS: Thirty-nine patients with thalassemia major were followed for a median of 16.3 yr (range 2-28). Individual mean serum ferritin level during the study period was calculated using repeated annual measurements. Bone DFO toxicity was assessed by wrist and spine radiographs; endocrine dysfunction by anthropometric measurements and pubertal stage; and hypogonadotropic hypogonadism by lack of luteinizing hormone response to gonadotropin-releasing hormone. RESULTS: Chelation therapy was initiated at median age 4.9 yr. Mean serum ferritin level during the study period was 2698 +/- 1444 ng/mL. Hypogonadism was noted in 59% of the patients who reached pubertal age, and short stature was found in 36% of patients who reached final height. Mean ferritin level of 2500 ng/mL during puberty was the cut-off for hypogonadism, and ferritin level of 3000 ng/mL during prepuberty was the cut-off for final short stature. None of the patients who attained final height had signs of DFO bone toxicity. CONCLUSIONS: High serum ferritin levels during puberty are a risk factor for hypogonadism, and high serum ferritin levels during the first decade of life predict final short stature. It remains to be determined whether improving chelation by earlier initiation of DFO or by the combined use of DFO and deferiprone will lead to better growth and sexual development without DFO toxicity.

Adolescent↗

Prevalence of the H63D mutation of the HFE in north India: its presence does not cause iron overload in beta thalassemia trait.

OBJECTIVES: To determine the allele frequency in the north Indian population of the two mutations in the HFE gene, the C282Y and H63D, which are responsible for causing hereditary haemochromatosis particularly in Caucasians of north European descent. We also wanted to correlate these mutations with the iron status in beta thalassemia traits. PATIENTS AND METHODS: Sixty normal subjects and 215 individuals with beta thalassemia trait from north India were screened for the C282Y and H63D by polymerase chain reaction-restriction fragment-length polymorphism (PCR-RFLP). We studied the iron status in these subjects and correlated the same with the HFE gene mutations. RESULTS: On screening for the C282Y gene mutation, all individuals were detected to be of the wild-type. The overall allele frequency of H63D was 9.09% with three individuals being homozygous for 63D. No statistically significant difference in the iron status was detected between the individuals of the wild-type and mutant for H63D. Haplotyping of the homozygous 63D alleles revealed the pattern to be identical to the Europeans. CONCLUSIONS: Our study shows that H63D is prevalent and C282Y is rare in north Indians and the presence of 63D mutation does not increase body iron as measured by serum ferritin in beta thalassemia traits. Haplotype of H63D gene mutation is of an European haplotype, indicating a common origin.

Alleles↗

A comparison of magnetic resonance imaging and cardiac biopsy in the evaluation of heart iron overload in patients with beta-thalassemia major.

OBJECTIVES: To apply magnetic resonance imaging (MRI) for the assessment of myocardial iron deposition in patients with beta-thalassemia and compare the results with cardiac biopsy data. BACKGROUND: Myocardial iron accumulation is the main cause for cardiac complications in beta-thalassemia. METHODS: Twenty-five consecutive thalassemic patients were studied using a 0.5-T (Tesla) system, ECG-gated, with echo time (TE) = 17-68 ms. T2 relaxation time of the interventricular septum was calculated assuming simple monoexponential decay. A heart T2 relaxation time value of 32 ms was used for the discrimination between high and low iron deposition. Heart biopsy was performed within a week after the MRI study. Patients with stainable iron in more than 50% of the myofibrils were graded as having severe iron deposition. A serum ferritin level below 2000 ng/mL was considered as an indication of successful chelation. RESULTS: Seven of the 25 patients had heart biopsy indicative of low iron deposition (Group L) and the remaining 18 patients had heart biopsy indicative of high iron deposition (Group H). T2 relaxation time of the heart (T2H) was lower in Group H compared to Group L (31.5 +/- 3.9 (range: 28-40) ms vs. 35.7 +/- 3.7 (range: 29-40) ms, P = 0.026). The T2H was in agreement with heart biopsy in 86% of the patients in Group L and in 78% of the patients in Group H (overall agreement 80%). Similarly, serum ferritin levels were in agreement with heart biopsy in 28% and 88%, respectively (overall agreement 72%). In Group L, MRI was in better agreement with biopsy compared to serum ferritin (86% vs. 28%, P < 0.05). A receiver operating characteristic curve (ROC) analysis confirmed that a T2 relaxation time of 32 ms had the highest discriminating ability for the corresponding biopsy outcome. CONCLUSIONS: Heart T2 relaxation time appears in agreement with cardiac biopsy, both in high and low iron deposition, and may become a useful non-invasive index in beta-thalassemia.

Adult↗

Neurosecretory dysfunction of growth hormone secretion in thalassemia major.

The growth retardation of children with thalassemia major is multifactorial. Along the endocrine axis of growth hormone (GH), serum somatomedin has been shown to be deficient and GH response to GH-releasing hormone impaired, while GH response to provocative stimuli is normal. We studied the spontaneous secretion of GH in seven patients with thalassemia major and growth retardation. Three of the patients were hypothyroid, and the other four were euthyroid. Spontaneous secretion of GH in all seven patients was subnormal: the number of pulses, the mean pulse amplitude, and the integrated concentration of GH were all lower than in 14 age- and sex-matched (10 pubertal and 4 prepubertal) control subjects. GH response to provocative stimuli was normal in the euthyroid patients. This pattern of response corresponds with the definition of neurosecretory dysfunction of GH secretion. It is concluded that the growth retardation of patients with thalassemia major is partly due to neurosecretory dysfunction of GH secretion.

Adolescent↗

Lived experiences of mothers caring for children with thalassemia major in Thailand.

ISSUES AND PURPOSE: Thalassemic patients must be given continuous treatment throughout their lives due to the physical and psychological effects of their disorder; their families also are impacted. This qualitative study explored the lived experiences of 15 mothers of children with thalassemia major by conducting semistructured interviews; the data were analyzed utilizing content analysis. CONCLUSION: Six themes were identified: lack of knowledge about thalassemia, psychosocial problems, concerns for the future, social support systems, financial difficulty, and the effectiveness of healthcare services. PRACTICE IMPLICATIONS: These findings suggest that a holistic, culturally sensitive nursing approach should be considered when caring for children with thalassemia.

Adaptation, Psychological↗

alpha Thalassemia and the expression of hemoglobin G-Philadelphia.

The findings presented for these two families help to explain the inheritance of alpha thalassemia, alpha-chain variants, and the relative expression of alpha genes. An 18.0-kb EcoRI fragment contains only one functional alpha gene, whereas a 20.5-kb fragment contains two. Individuals homozygous for the 18.0-kb EcoRI fragment also lack the 4.1-kb HindIII fragment that normally connects the centers of the duplicated alpha genes. These findings are consistent with a deletion involving the 5' alpha-gene locus. Presence of alpha G-Philadelphia in both families was found in association with the 18.0-kb EcoRI fragment; this short fragment was also found in an individual with alpha A. Inheritance of alpha G-Philadelphia at one alpha-gene locus was therefore also linked to the inheritance of alpha thalassemia due to a deletion involving the second alpha gene. The high percentage (46% to 48%) of alpha G found in some family members was due to alpha-thalassemia trait, or deletion of two alpha genes (-alpha G/-alpha); others with levels of variant of 32% to 34% were shown to have three functional alpha genes (-alpha G/alpha alpha). The genetic expression of the four normal alpha genes therefore appears to be equal and furthermore implies the existence of separate independently functioning transcriptional units for each of these genes in humans. It would be interesting to analyze the alpha genes in Afro-Americans reported to have alpha G-Philadelphia in the 20% to 25% range to determine whether the inheritance of alpha G can be linked to a normal alpha gene.

Base Sequence↗

The clinical significance of magnesium depletion in thalassemia.

(1) Mg depletion in a population of 14 patients with thalassemia was documented by low serum Mg levels, abnormal Mg tolerance tests, and/or symptoms responsive to Mg therapy. (2) The observation that some degree of Mg depletion was present even in younger asymptomatic patients needs further investigation and suggests that monitoring of Mg status should be included in the routine care of patients with thalassemia. (3) Careful consideration should be given to the possibility that in patients with thalassemia early continuous supplementation with Mg is needed and may have a beneficial influence on the heart's response to chronic Fe overload and chronic hypoxemia.

Adolescent↗

Vitamin E deficiency due to increased consumption in beta-thalassemia and in Gaucher's disease.

Plasma vitamin E levels were found to be decreased (less than 0.5 mg) in thalassemia and in 17 out of 20 patients with Gaucher's disease, where the levels were two standard deviations below the normal mean value. In the latter, the decrease in vitamin E levels correlated with the severity of the clinical expression of the disease and correlated inversely with the degree of hepatosplenomegaly and serum tartrate-resistant acid phosphatase activity. In both diseases, there was no evidence for intestinal malabsorption of the lipid-soluble vitamin. In spite of the different etiology, pathophysiology, and clinical expression, severe vitamin E deficiency could result in both diseases by a common mechanism. In thalassemia, rapid consumption of vitamin E occurs while neutralizing oxidative damage in the pathological erythrocyte membranes and in other tissues. In Gaucher's disease, lysosomal accumulation of glucocerebroside may stimulate phagocytes into a maintained "respiratory burst" with excessive production of oxygen free radicals, resulting in increased utilization and eventual deficiency of vitamin E. Efficacy of antioxidant therapy was evaluated by administration of vitamin E with and without canthaxanthin, which has similar antioxidant properties to beta-carotene, to patients with beta-thalassemia. The results showed increased serum vitamin E levels and a decrease in the extent of erythrocyte lipid membrane peroxidation, while no significant changes occurred in hemoglobin levels and in transfusion requirements.

Child↗

Combined subcutaneous and high-dose intravenous deferoxamine therapy of thalassemia.

Although the preliminary findings are encouraging, to assess the effectiveness of the SHYD program on the long-term course of thalassemia, a larger patient population and longer treatment and follow-up period are needed. The presence of cardiac abnormalities in patients in Group I suggests that to prevent heart damage in thalassemia, it may be necessary to start the HTP and effective chelation therapy at a very young age, realizing that the amount of iron removed will be small. The finding that two of the four patients who survived to receive the largest amount of Fe/kg have intact spleens and another had splenectomy at age 24 suggests that, in these patients, the spleen may have had a protective role for the heart. If this observation is confirmed, it would provide evidence that removal of the spleen may adversely affect the long-term course of patients with thalassemia. Six years' experience with the SHYD program has not provided evidence for significant acute or chronic toxicity. This suggests that it might be safe to administer the i.v. treatments at home, a program that is anticipated for the future, as it would significantly reduce cost and possibly be more convenient.

Adolescent↗

Hematology of a murine beta-thalassemia: a longitudinal study.

Mice homozygous for a spontaneous mutation, in which the beta-major globin gene is deleted, have clinical symptoms of beta-thalassemia. These mice have a hypocellular, hypochromic, microcytic anemia that becomes more severe with increasing age. The defective red cell morphology, decreased osmotic fragility of erythrocytes and shortened red cell life span found in beta-thalassemic mice are similar to those observed in human beta-thalassemia. Synthesis of beta-globin is depressed but not as much as might be expected because the expression of the beta-minor globin gene is enhanced to encode two to three times more globin than in normal mice. Splenomegaly, an enlarged pool of stem cells for erythropoiesis, and iron overloading occur in older mice. The fact that these mice remain moderately healthy makes them a very suitable animal model in which to develop and test alternative techniques of gene therapy that could be successfully applied to the treatment of human thalassemia. Homozygous beta-thalassemic mice have large deposits of iron in their tissues, which might make these mice also useful for in vivo tests of the effectiveness and possible long-term side effects of newly developed iron chelators.

Animals↗