Thalassemia major 1995: older patients, new therapies

Advances in detection of hemoglobinopathies

Hemoglobin disorders are recognized as one of the most common inherited diseases worldwide. Detecting and characterizing variant hemoglobins and thalassemias depends primarily on clinical laboratory methods. Multiple biophysical, biochemical, and genetic assays are available to provide phenotypic or genotypic evidence of pathology. For many years conventional slab-gel electrophoresis and HPLC were the most commonly utilized laboratory methods. However, the field has rapidly expanded to regularly include capillary zone electrophoresis, molecular assays, and, more recently, mass spectrometric assays. Interpretation of these techniques is, in general, complicated because of the involvement of multiple polymorphic genes. Proper characterization of hemoglobin variants is necessary for diagnosis, primary prevention and genetic counseling for underlying disorders. This review provides an overview of the current hemoglobin analysis techniques, and also discusses technologies that have potential to translate into widespread clinical settings.

Evaluation of osteopathy in thalassemia by bone mineral densitometry and biochemical indices

OBJECTIVE

To evaluate osteopathy in thalassemia by bone mineral densitometry (BMD) and biochemical indices.

METHODS

Prospective review analysis with no follow up from 2006 to 2007 of 42 regularly transfused thalassemics aged 10-25 years (27 boys, 15 girls) was done. Anthropometry, pubertal stage and symptomatology were noted. Urinary C-terminal cross-linked telopeptide of type-1 collagen (Crosslaps) by ELISA; serum 25-OH vitamin D and osteocalcin by RIA; parathyroid hormone (PTH) and ferritin by chemiluminescence and IGF-1 by Enzyme immunoassay were evaluated. Dual Energy X-ray Absorptiometry (DEXA) of lumbar spine and femur was done on Lunar prodigy system. Data was entered and analyzed using the SPSS for Windows software. Mean comparisons were done by ANOVA 1 and data was compared using Chi-square test and p value < 0.05 was taken as significant.

RESULTS

Of 42 patients, 81% had osteoporosis by Z-score of DEXA. Urinary crosslaps was high in 55%; 36% had increased osteocalcin; 62% had low vitamin D levels; 38% had high parathyroid levels and IGF-1 was low in 52%. Mean serum ferritin level was 5344 ± 2855 ng/dl. There was statistical significance (p = 0.046) between chronological age and BMD. All 42 cases were divided into two groups: Group-1 (Normal DEXA), Group-2 (Abnormal DEXA) and analysis of biochemical indices between two groups showed no significant difference in any of the biochemical parameters.

CONCLUSION

This study revealed majority of thalassemics with inadequate chelation have bone resorption with advancing chronological age and BMD should be evaluated regularly for early diagnosis to prevent morbidity.

Comparison of Oral and Subcutaneous Iron Chelation Therapies in the Prevention of Major Endocrinopathies in β-Thalassemia Major Patients

While hypertransfusion and subcutaneous iron chelation therapy have increased longevity of patients with beta-thalassemia (thal) major, endocrinopathies have become more common and impair the quality of their lives. Additionally, subcutaneous iron chelation therapy is an uncomfortable experience and can prevent patients from regular compliance with iron chelation therapy. We compared the efficacy of oral deferiprone (L1) to subcutaneous desferrioxamine (DFO) chelation therapy for the prevention of major endocrinopathies (growth hormone insufficiency, diabetes mellitus and gonadal dysfunction) among patients with beta-thal major to see if we could offer these patients an easier and more painless way to reduce their body iron load and related endocrine complications.

Cord blood stem cell transplantation for haemoglobinopathies

Despite improvements in supportive care, patients with beta-thalassaemia major or sickle cell disease (SCD) may benefit from haematopoietic stem cell transplantation at some point during their lives. Human leucocyte antigen (HLA)-matched sibling bone marrow donors are not always available and alternative sources of stem cells have been sought, including related and unrelated donor cord blood transplants (CBT). The outcome of CBT from related donors for the treatment of both thalassaemia major and SCD is now approaching that for bone marrow transplantation, with around 90% of patients surviving disease-free. The main complication is graft rejection, which may be reduced by increasing pretransplant immune suppression. Transplant-related mortality following HLA-identical matched related donor CBT is extremely low but is significant in the small series of unrelated and/or mis-matched donor CBT. The principal limitation to extending the use of CB stem cells for the cure of haemoglobinopathies is the need to better understand the mechanisms of action and optimal conditioning regimens used to secure long-term engraftment while minimizing morbidity and mortality. Further biological studies and clinical trials are needed to address this aim.

Endocrine gland abnormalities in thalassemia major: a brief review

Thalassemia major (beta-thalassemia) affects a significant segment of the population in certain areas of the world. Alterations in migration patterns have changed the geographic distribution of this disease and made it a worldwide health problem. Over the course of the past 2-3 decades hypertransfusion therapy has significantly increased the life expectancy, and improved the quality of life of these patients. At the same time there has been an increase in the frequency of complications of this therapy caused by iron overload. Endocrine gland abnormalities contributed little to the morbidity or mortality of beta-thalassemia in the past. As a result of hypertransfusion therapy and increased longevity, however, endocrinopathies have become more common and contribute significantly to morbidity in these patients. In this article we briefly review the current understanding of endocrine gland abnormalities, primarily caused by iron overload, in patients with thalassemia major.

Techniques and clinical outcomes of laparoscopic cholecystectomy in adult patients with beta-thalassemias

Beta-thalassemia, which results from a reduced production of beta-globin chain of hemoglobin, is a common single gene disorder with an extremely heterogeneous clinical picture. Its presentation may vary from mild anemia in beta-thalassemia minor to severe and life-threatening anemia in beta-thalassemia major. Recent advances in supportive treatment of beta-thalassemia major have resulted in substantial increase in survival in these patients, and an increasing number of these patients reach adolescence and adulthood. The incidence of cholelithiasis is reported to be increased in these patients. Although laparoscopic cholecystectomy (LC) has become the gold standard treatment of symptomatic gallstone disease, its experience in adult beta-thalassemic patients has been limited. From May 1992 through April 2000, 10 consecutive adult beta-thalassemic patients with symptomatic gallstone underwent LC at our institution. Data were obtained on the type of beta-thalassemia, presentation, preoperative laboratory findings, history of preoperative transfusion, postoperative complications, postoperative analgesic requirement, length of hospital stay, and follow-up. All operations were completed laparoscopically. The mean operative time was 98.5 minutes. The postoperative analgesic requirement was minimal. There was no mortality. One patient developed fever postoperatively due to lung atelectasis that was managed conservatively. The mean hospital stay was 3 days. Laparoscopic cholecystectomy is feasible, safe, and effective in the treatment of adult beta-thalassemic patients with symptomatic gallstone disease. Technical adjustments are required when operating on patients with beta-thalassemia major.

Thalassemia and abnormal hemoglobin

Thalassemia and abnormal hemoglobins are common genetic disorders in Asia. Thalassemia is not only an important public health problem but also a socio-economic problem of many countries in the region. The approach to deal with the thalassemic problem is to prevent and control birth of new cases. This requires an accurate identification of the couple at high risk for thalassemia. However, the diagnosis of thalassemia carrier states need several tests which are not practical for screening the population at large. Recently we have used two simple laboratory tests to screen for potential thalassemia carriers and hemoglobin E individuals. There is also a new development in using the automatic HPLC to diagnose thalassemic diseases and the carriers. This system gives both qualitative and quantitative analysis of hemoglobin components in the same run with good precision and reproducibility. The system has been applied to study thalassemia and abnormal Hb in adult and cord blood. This system has enabled us to do both prenatal and postnatal diagnosis of thalassemia within the few minutes. However, none of these screening tests can accurately give specific diagnosis of the thalassemia genotype. Specific thalassemia mutation can be carried out by DNA analysis. Many DNA techniques have been used for point mutation detection and small deletion. For the last few years there is a development of DNA chip technology that has been applied for thalassemia mutation as well. Clinically, thalassemia is very heterogeneous in the manifestation. In spite of seemingly identical genotypes, severity of beta thalassemic patients can vary greatly. Heterogeneity in the clinical manifestation of beta thalassemic diseases may occur from the nature of beta globin gene mutation, alpha thalassemia gene interaction and difference in the amount of Hb F production which is partly associated with a specific beta globin haplotype. However, there is still some beta thalassemia cases that have a mild clinical symptom without those known genetic fators interaction suggesting that there are other additional factors responsible for the mildness of the disease.

New trends in the treatment of beta-thalassemia

Thalassemia is the world's most common hereditary disease, and is a paradigm of monogenic genetic diseases. Because of increased population mobility, the disease is found today throughout the world, even in places far from the tropical areas in which it arose. Therapy of thalassemia has in the past been confined to transfusion and chelation. Recently, novel modes of therapy have been developed for thalassemia, based on the pathophysiology and molecular pathology of the disease, both of which have been extensively studied. This review will discuss the therapeutic modalities currently in use for the supportive treatment of thalassemia, both those that are standard therapy and those that are in clinical trials. We will include transfusion, chelation (intravenous and oral), antioxidants and various inducers of fetal hemoglobin (hydroxyurea, erythropoietin, butyrates, hemin). Most of the newer therapies are suitable primarily for thalassemia intermedia patients. In addition, the treatment modalities currently in use for the curative treatment of thalassemia major will be discussed, including bone marrow transplantation in its various forms. Experimental therapeutic methods, such as intrauterine bone marrow transplantation and gene therapy, are included. Physicians caring for thalassemia patients have an increasing variety of treatment options available. Future clinical studies will determine the place of newer agents and modalities in improving the quality of life as well as the life expectancy of thalassemia patients.

Pregnancy in patients with well-treated beta-thalassemia: outcome for mothers and newborn infants

OBJECTIVE

Our purpose was to investigate the course and outcome of pregnancy in women with well-treated beta-thalassemia.

STUDY DESIGN

Twenty-two pregnancies, including one twin pregnancy, in 19 women were studied. Pregnancy was advised when patients had received a prolonged intensive treatment with hypertransfusions and iron chelation and had echocardiographically normal resting left ventricular performance. All conceptions were spontaneous. Cardiac function, along with hematologic, endocrinologic, and hepatic parameters were initially assessed and monitored throughout pregnancy and for 2 to 9 years post partum. Babies were delivered by elective cesarean section.

RESULTS

Twenty-one healthy newborn infants were delivered. A spontaneous abortion and a case of exomphalos also occurred. Gestation, delivery, and recovery were surprisingly uneventful, and no significant cardiac complications were encountered.

CONCLUSION

Pregnancy can be safe for mothers and babies, provided that women with thalassemia have been started early on intensive treatment and have a normal resting cardiac performance.

Severe thalassaemia intermedia: clinical problems in the absence of hypertransfusion

In many of the parts of the world where thalassaemia is common, the blood supply is inadequate or unsafe, and desferrioxamine is too expensive for routine use. We classify some patients as having 'severe thalassaemia intermedia', i.e. those with moderately severe thalassaemia who can survive without regular transfusions, but who are at risk of many complications which are reviewed here. These include bone deformity and fractures, extramedullary haemopoietic tumours, leg ulcers, autoimmune haemolysis and, especially after splenectomy, thromboembolism and infection. An increase in the quality and safety of the blood supply, and a cheaper and/or oral iron chelator, would enable more of these patients to be treated as thalassaemia major and have improved survival and quality of life.

Diagnosis and management of iron-induced heart disease in Cooley's anemia

Patients with homozygous beta-thalassemia are chronically transfused and, if not assiduously chelated, are at risk for cardiac dysfunction. Available data suggest that even in optimally chelated patients, cardiac pathology is abnormal secondary to iron deposition, fibrosis, hypertrophy, and the structural effects of chronic anemia. Evidence of myopericarditis may also be found. Cardiac performance is usually only subtly affected, primarily with diastolic abnormalities not routinely detected on echocardiograms or nuclear scan. In poorly chelated patients, severe heart failure occurs and is easily predictable but invariably fatal, despite treatment with diuretics, vasodilators, inotropes, and antiarrhythmics. Based on successful prevention of heart failure with ACE inhibitors in other forms of cardiomyopathy, we suggest multicenter trials to explore methods to stabilize cardiac function in patients at risk for iron-induced heart disease. Long-term adverse effects of iron deposition, diastolic dysfunction, and abnormal hormone regulation need to be quantitated in patients reaching their third and fourth decades when the potential for ischemic cardiac disease could compound cardiac dysfunction.

Transfusion-dependent homozygous beta-thalassaemia major: successful pregnancy in five cases

beta-Thalassaemia major is a severe, transfusion-dependent anaemia that also causes infertility due to iron deposition to endocrine organs. Very few pregnancies have been reported among such patients. In this report we describe the evolution and successful outcome of pregnancy in 5 Greek women with beta-thalassaemia major. There were four full-term and one preterm deliveries of two normal and three small for the date neonates. Cardiovascular changes related to gestation may aggravate the underlying multiorgan damage of the pregnant mother and predispose to poor fetal growth and development. All five patients followed a strict transfusion regimen in order to maintain the haemoglobin level above 10 g/dl. The inadvertent administration of desferrioxamine in one patient until the 8th gestational week did not seem to have any serious effects on the development and well-being of the fetus. Although pregnancy is not contraindicated in beta-thalassaemia major, intensive individualized care is required if it is to be safe for the mother, and have a reasonably good chance of producing a healthy child.

Experimental therapy

Bone marrow transplantation, hydroxyurea therapy in children and in patients with sickling disorders other than sickle cell anemia, and prophylactic transfusion for prevention of stroke in children are currently being evaluated as treatments for patients with sickle cell disease. Long-term complications of each of these treatments are incompletely understood. Attempts to inhibit sickling by lowering intracellular hemoglobin concentration are still in progress. Combinations of therapeutic agents with different modes of action, and development of more effective treatment schedules, may further improve the outlook of patients with sickling disorders.