Fertility and Pregnancy in Women with Transfusion-Dependent Thalassemia.

As more women with transfusion-dependent thalassemia are seeking pregnancy, ensuring the best outcomes for both the mother and baby requires concerted, collaborative efforts between practitioners and the family. Proactive counseling, early fertility evaluation, recent developments in reproductive technology, and optimal management of iron overload, have resulted in more successful pregnancies and the birth of healthy newborns. With advances in technology for prenatal screening and increased awareness to perform screening for hemoglobinopathies, healthy pregnancy outcomes have become the expectation. Topics that require further study include management that allows fertility preservation, improved non-invasive prenatal diagnosis methods for affected fetuses, the use of chelation therapy during pregnancy, and indications for and duration of anticoagulation.

Thalassaemia.

Inherited haemoglobin disorders, including thalassaemia and sickle-cell disease, are the most common monogenic diseases worldwide. Several clinical forms of α-thalassaemia and ß-thalassaemia, including the co-inheritance of ß-thalassaemia with haemoglobin E resulting in haemoglobin E/ß-thalassaemia, have been described. The disease hallmarks include imbalance in the α/ß-globin chain ratio, ineffective erythropoiesis, chronic haemolytic anaemia, compensatory haemopoietic expansion, hypercoagulability, and increased intestinal iron absorption. The complications of iron overload, arising from transfusions that represent the basis of disease management in most patients with severe thalassaemia, might further complicate the clinical phenotype. These pathophysiological mechanisms lead to an array of clinical manifestations involving numerous organ systems. Conventional management primarily relies on transfusion and iron-chelation therapy, as well as splenectomy in specific cases. An increased understanding of the molecular and pathogenic factors that govern the disease process have suggested routes for the development of new therapeutic approaches that address the underlying chain imbalance, ineffective erythropoiesis, and iron dysregulation, with several agents being evaluated in preclinical models and clinical trials.

Iron and oxidative stress in cardiomyopathy in thalassemia.

With repeated blood transfusions, patients with thalassemia major rapidly become loaded with iron, often surpassing hepatic metal accumulation capacity within ferritin shells and infiltrating heart and endocrine organs. That pathological scenario contrasts with the physiological one, which is characterized by an efficient maintenance of all plasma iron bound to circulating transferrin, due to a tight control of iron ingress into plasma by the hormone hepcidin. Within cells, most of the acquired iron becomes protein-associated, as once released from endocytosed transferrin, it is used within mitochondria for the synthesis of protein prosthetic groups or it is incorporated into enzyme active centers or alternatively sequestered within ferritin shells. A few cell types also express the iron extrusion transporter ferroportin, which is under the negative control of circulating hepcidin. However, that system only backs up the major cell regulated iron uptake/storage machinery that is poised to maintain a basal level of labile cellular iron for metabolic purposes without incurring potentially toxic scenarios. In thalassemia and other transfusion iron-loading conditions, once transferrin saturation exceeds about 70%, labile forms of iron enter the circulation and can gain access to various types of cells via resident transporters or channels. Within cells, they can attain levels that exceed their ability to chemically cope with labile iron, which has a propensity for generating reactive oxygen species (ROS), thereby inducing oxidative damage. This scenario occurs in the heart of hypertransfused thalassemia major patients who do not receive adequate iron-chelation therapy. Iron that accumulates in cardiomyocytes forms agglomerates that are detected by T2* MRI. The labile forms of iron infiltrate the mitochondria and damage cells by inducing noxious ROS formation, resulting in heart failure. The very rapid relief of cardiac dysfunction seen after intensive iron-chelation therapy in some patients with thalassemia major is thought to be due to the relief of the cardiac mitochondrial dysfunction caused by oxidative stress or to the removal of labile iron interference with calcium fluxes through cardiac calcium channels. In fact, improvement occurs well before there is any significant improvement in the total level of cardiac iron loading. The oral iron chelator deferiprone, because of its small size and neutral charge, demonstrably enters cells and chelates labile iron, thereby rapidly reducing ROS formation, allowing better mitochondrial activity and improved cardiac function. Deferiprone may also rapidly improve arrhythmias in patients who do not have excessive cardiac iron. It maintains the flux of iron in the direction hemosiderin to ferritin to free iron, and it allows clearance of cardiac iron in the presence of other iron chelators or when used alone. To date, the most commonly used chelator combination therapy is deferoxamine plus deferiprone, whereas other combinations are in the process of assessment. In summary, it is imperative that patients with thalassemia major have iron chelators continuously present in their circulation to prevent exposure of the heart to labile iron, reduce cardiac toxicity, and improve cardiac function.

Selected highlights of the VIII International Symposium of Clinicians for Endocrinopathies in Thalassemia and Adolescent Medicine (ICET-A) on Growth, Puberty and Endocrine Complications in Thalassaemia. Auditorium of the Sultan Qaboos University (SQU) Muscat (Sultanate of Oman), 20th of December 2014.

The VIII ICET-A International Symposium was held in Muscat (Sultanate of Oman) on the 20th of December, 2014. The symposium included four sessions on a wide range of topics covering growth disorders and endocrine complications in thalassaemia. Despite the fact that endocrine complications are very common in multi-transfused thalassaemia patients a recent survey conducted by the International Network of Clinicians for Endocrinopathies in Thalassemia and Adolescent Medicine (ICET-A) in 2014 in Acitrezza (Catania, Italy) showed that the major difficulties reported by hematologists or pediatricians experienced in thalassaemias or thalassaemia syndromes in following endocrine complications included: Lack of familiarity with medical treatment of endocrine complications, interpretation of endocrine tests, lack of collaboration and on-time consultation between thalassaemic centres supervised by haematologists and endocrinologists. Endocrine monitoring of growth, pubertal development, reproductive ability and endocrine function in general are essential to achieve a good quality of life as well as controlling the pain which results from the defects of bone structure, all of which increase with the age of patients. Such comprehensive care is best provided by coordinated, multidisciplinary teams working in expert centres. The multidisciplinary team must include an endocrinologist, preferably someone experienced in the management of hormonal deficiencies caused early in life by transfusion-induced iron overload.

Treating iron overload in patients with non-transfusion-dependent thalassemia.

Despite receiving no or only occasional blood transfusions, patients with non-transfusion-dependent thalassemia (NTDT) have increased intestinal iron absorption and can accumulate iron to levels comparable with transfusion-dependent patients. This iron accumulation occurs more slowly in NTDT patients compared to transfusion-dependent thalassemia patients, and complications do not arise until later in life. It remains crucial for these patients' health to monitor and appropriately treat their iron burden. Based on recent data, including a randomized clinical trial on iron chelation in NTDT, a simple iron chelation treatment algorithm is presented to assist physicians with monitoring iron burden and initiating chelation therapy in this group of patients.

Quality of life in thalassemia: a comparison of SF-36 results from the thalassemia longitudinal cohort to reported literature and the US norms.

Thalassemia is a chronic, inherited blood disorder, which, in its most severe form, causes life-threatening anemia. Advances in treatment have led to increased life expectancy however the need for chronic blood transfusions and chelation therapy remains a significant burden for patients. Our study compared health related quality of life (HRQOL) from the Thalassemia Clinical Research Network's (TCRNs) Thalassemia Longitudinal Cohort (TLC) study to US norms and assessed association with clinical variables. There were 264 patients over age 14 who completed the Medical Outcomes Study 36-Item Short Form Health Survey version 2 (SF36v2) baseline assessment. When compared to US norms, TLC patients had statistically significant (P < 0.05) worse HRQOL on five of the eight subscales (physical functioning, role-physical, general health, social functioning, and role-emotional) and on both summary scales (physical component summary and mental component summary). Women, older patients, and those with more disease complications and side effects from chelation reported lower HRQOL. In general, adolescents and adults with thalassemia report worse HRQOL than the US population, despite contemporary therapy. The SF-36 should become a standard instrument for assessing HRQOL in thalassemia to determine predictors of low HRQOL which may be better addressed by a multidisciplinary team.

The role of antioxidants and iron chelators in the treatment of oxidative stress in thalassemia.

On the basis of all the presented data, one can conclude that oxidative stress plays a major role in the pathophysiology of thalassemia and other congenital and acquired hemolytic anemias. Free extracellular (labile plasma iron, LPI) and intracellular (labile iron pool, LIP) iron species that have been identified in thalassemic blood cells are responsible for generation of oxidative stress by catalyzing formation of oxygen radicals over the antioxidant capacity of the cell. Consequently, there is a rationale for iron chelation to eliminate the free-iron species, which in this respect, act like antioxidants. In addition, antioxidants such as vitamin E and polyphenols are also capable of ameliorating increased oxidative stress parameters and, given together with iron chelators, may provide a substantial improvement in the pathophysiology of hemolytic anemias and particularly in thalassemia.

Critical appraisal of growth retardation and pubertal disturbances in thalassemia.

Growth and pubertal disturbances are the commonest endocrinopathies in homozygous thalassemia, accounting for significant morbidity in 70-80% children and adolescents globally. This review focuses on the pathophysiology of the endocrinopathy from a historical perspective and altered natural history induced by better care due to transfusion and chelation therapy. We have also discussed clinical features, diagnosis, and management strategies of growth retardation, sexual infantilism, pubertal aberrations, and scope of growth hormone, sex steroids, and other endocrine therapies. The article also emphasizes current and future strategies for screening, monitoring of growth and pubertal disturbances, and early intervention for the restoration of fertility potential and bone mass in the affected individuals.

Influence of iron chelators on myocardial iron and cardiac function in transfusion-dependent thalassaemia: a systematic review and meta-analysis.

Iron chelators have dramatically prolonged the life expectancy of patients with transfusion-dependent thalassaemia, but their precise clinical benefit in reducing the myocardial iron burden and improving cardiac function is unknown. This systematic review and meta-analysis included published clinical trials that assessed the efficacy of iron chelators in regularly transfused patients of thalassaemia major for two commonly reported outcomes - myocardial iron content and left ventricular ejection fraction (LVEF). The meta-analysis of 392 patients for myocardial iron content and 291 patients for LVEF showed that (i) iron chelators reduced cardiac iron content by 23.9% (95% confidence interval 17.3-29.8%); (ii) there was no significant difference between the amount of iron reduced by deferoxamine and deferiprone (P = 0.9504); and (iii) LVEF was not significantly influenced by iron chelators - summary Hedge's g 0.13 (95% confidence interval -0.10-0.36). A significant publication bias existed for LVEF (Egger's P = 0.049) but not for myocardial iron (Egger's P = 0.871). Our results indicate that iron chelators significantly reduce myocardial iron content. Further, the choice of deferoxamine versus deferiprone may rest on factors other than their efficacy to reduce cardiac iron load.

Effects of chelation therapy on cardiac function improvement in thalassemia patients: literature review and the Taiwanese experience.

The iron chelators deferoxamine (DFO) and deferiprone (L1) have demonstrated their ability to normalize cardiac function in patients with iron overload-induced cardiac disease. However, conventional chelation with subcutaneous DFO fails to prevent iron deposition in two-thirds of thalassemia major patients, placing them at risk of heart failure and its complications. Deferiprone appears to be more effective in cardiac iron removal. The detection and management of heart complications have improved dramatically over the last 7 years. Non invasive techniques of quantifying iron burden via magnetic resonance imaging (MRI) have been validated. A better understanding of cardiac pathophysiology and improved ability to detect at-risk populations are yielding better outcomes and reduced morbidity. We continue to appraise readily available bedside tools for monitoring thalassemia patients with heart complications, and here we summarize studies from the literature and our own findings. Deferiprone chelation was found to be of statistically significant benefit in upgrading cardiac function and reducing iron accumulation. The use of echocardiography and MRI to closely monitor cardiac functions associated with iron overload complications and mortality has proved quite practical.

Assessmrent of iron overload in thalassaemic patients by magnetic resonance imaging: a pilot study.

The patients of thalassaemia major need repeated blood transfusion which leads to excess iron deposition in various organs like liver, heart, pituitary etc. This iron accumulation causes various complications and ultimately organs' failure. There is no non-invasive, standard and reliable method to know the status of iron overload in various organs of the body. This paper attempts to use magnetic resonance imaging to know the liver iron overload in 8 thalassaemic patients as a pilot study. Eight children suffering with thalassaemia and 3 controls who were the normal siblings of the patient group underwent magnetic resonance imaging of the abdomen using spin-echo T, weighted sequence. Blood serum ferritin levels in the patients' group were also determined on the same day of magnetic resonance imaging examination. It was observed that the ratio of magnetic resonance imaging signal intensity (in spin-echo T1 weighted image) in paraspinous muscle to liver was significantly different in normal control (0.65) compared to that in thalassaemia patients (2.1 to 11.4 depending upon extent of iron deposition). The magnetic resonance signal intensity ratio correlated with the blood serum ferritin level of patients (p = 0.01) which is generally taken as indirect measure of body iron burden. Spin-echo sequence is the simplest imaging sequence and it increases the chance of its routine use. The study concludes that magnetic resonance imaging has good potential to quantify the liver iron deposition non-invasively and may denote the efficacy of iron-chelation therapy which is used to reduce the body iron burden in these patients.

Thalassemia.

New developments in the epidemiology, treatment and prognosis of thalassemia have dramatically altered the approach to the care of affected patients, and these developments are likely to have an even greater impact in the next few years. Demographic changes have required an awareness and understanding of the unique features of thalassemia disorders that were previously uncommon in North America but are now seen more frequently in children and recognized more consistently in adults. New methods for measuring tissue iron accumulation and new drugs to remove excessive iron are advancing two of the most challenging areas in the management of thalassemia as well as other transfusion-dependent disorders. Improved survival of patients with thalassemia has given new importance to adult complications such as endocrinopathies and hepatitis that have a major impact on the quality of life. This chapter describes how these changes are redefining the clinical management of thalassemia. In Section I, Dr. Renzo Galanello describes recent advances in iron chelation therapy. Several new chelators are either licensed in some countries, are in clinical trials or are in the late stages of preclinical development. Some of these iron chelators, such as deferiprone (DFP) and ICL670, are orally active. Others, such as hydroxybenzyl-ethylenediamine-diacetic acid (HBED) and starch deferoxamine, require parenteral administration but may be effective with less frequent administration than is currently required for deferoxamine. Chelation therapy employing two chelators offers the possibility of more effective removal of iron without compromising safety or compliance. Other strategies for chelation therapy may take advantage of the ability of particular chelators to remove iron from specific target organs such as the heart and the liver. In Section II, Dr. Dudley Pennell addresses cardiac iron overload, the most frequent cause of death from chronic transfusion therapy. The cardiac complications related to excessive iron may result from long-term iron deposition in vulnerable areas or may be due to the more immediate effects of nontransferrin-bound iron. Cardiac disease is reversible in some patients with intensive iron chelation therapy, but identification of cardiac problems prior to the onset of serious arrhythmias or congestive heart failure has proven difficult. New methods using magnetic resonance imaging (MRI) have recently been developed to assess cardiac iron loading, and studies suggest a clinically useful relationship between the results using these techniques and critical measures of cardiac function. Measurements such as T2* may help guide chelation therapy in individual patients and may also enhance the assessment of new chelators in clinical trials. The use of MRI-based technology also holds promise for wider application of non-invasive assessment of cardiac iron in the management of patients with thalassemia. In Section III, Dr. Melody Cunningham describes some of the important complications of thalassemia that are emerging as patients survive into adulthood. Hepatitis C infection is present in the majority of patients older than 25 years. However, antiviral therapy in patients with thalassemia has been held back by the absence of large clinical trials and concern about ribavirin-induced hemolysis. More aggressive approaches to the treatment of hepatitis C may be particularly valuable because of the additive risks for cirrhosis and hepatocellular carcinoma that are posed by infection and iron overload. Thrombosis is recognized with increasing frequency as a significant complication of thalassemia major and thalassemia intermedia, and pulmonary hypertension is now the focus of intense study. Risk factors for thrombosis such as splenectomy are being identified and new approaches to anticoagulation are being initiated. Pregnancies in women with thalassemia are increasingly common with and without hormonal therapy, and require a better understanding of the risks of iron overload and cardiac disease in the mother and exposure of the fetus to iron chelators. In Section IV, Dr. Elliott Vichinsky describes the dramatic changes in the epidemiology of thalassemia in North America. Hemoglobin E-beta thalassemia is seen with increasing frequency and poses a particular challenge because of the wide variability in clinical severity. Some affected patients may require little or no intervention, while others need chronic transfusion therapy and may be appropriate candidates for hematopoietic stem cell transplantation. Enhancers of fetal hemoglobin production may have a unique role in Hb E-beta thalassemia since a modest increase in hemoglobin level may confer substantial clinical benefits. Alpha thalassemia is also being recognized with increasing frequency in North America, and newborn screening for Hemoglobin Barts in some states is leading to early detection of Hb H disease and Hb H Constant Spring. New data clarify the importance of distinguishing these two disorders because of the increased severity associated with Hb H Constant Spring. The use of intrauterine transfusions to sustain the viability of fetuses with homozygous alpha thalassemia has created a new population of patients with severe thalassemia and has raised new and complex issues in genetic counseling for parents with alpha thalassemia trait.

Short stature and truncal shortening in transfusion dependent thalassemia patients: results from a thalassemia center in Malaysia.

One of the major complications in patients with transfusion dependent thalassemia is growth impairment secondary to iron overload. We studied the growth status in 66 patients with beta-thalassemia major and HbE-beta thalassemia who were transfusion dependent, aged from 2 to 24 years, and 66 controls matched for sex and age. The prevalence of short stature in transfusion-dependent thalassemics was 54.5% compared to 4.5% in control group (p<0.001). Short stature was more prevalent in those above the age of 10 years in this study group (83.3% vs 16.7%). Transfusion dependent thalassemics with short stature were found to have significantly lower mean standing height standard deviation scores (SDS), sitting height SDS and subischial leg length SDS values (p<0.001). There was also a significant difference between the mean sitting height SDS and the mean subischial leg length SDS in our thalassemics with short stature, suggesting that the short stature was due to disproportionate truncal shortening. Serum ferritin levels were significantly higher in transfusion dependent thalassemics who were short compared to those who were of normal height (p = 0.002). However, the mean pre-transfusion hemoglobin levels did not differ significantly between patients with short stature and those with normal height (p = 0.216). The prevalence of short stature also did not differ significantly between those with beta-thalassemia major and those with HbE-beta thalassemia (p = 0.32). This study highlighted the importance of providing optimal treatment in these patients, including monitoring of growth parameters and optimizing iron chelation therapy.

Chelation therapy in patients with thalassemia using the orally active iron chelator deferiprone (L1).

BACKGROUND AND OBJECTIVE: Excessive hemosiderosis is the main reason for the multi-organ failure observed in multitransfused patients. Deferiprone (1,2-dimethyl-3-hydroxy-pyridine-4-one, L1) is an orally active iron chelator mainly excreted via urine. We conducted a study in order to determine the efficacy and safety of L1 in Greek thalassemic patients. DESIGN AND METHODS: A group of 11 thalassaemic patients entered the study; L1, the Cipla formulation for deferiprone, at a daily dose of 75-100 mg/kg bw t.i.d. was used. After giving informed consent all patients were subjected to clinical examination and biological tests. RESULTS: All patients tolerated the L1 well; there were no significant side effects (except for slight gastrointestinal disturbances for the first days). The net urinary iron excretion ranged from 6.96 to 26.1 mg/24h. Serum ferritin declined within 4-6 months in most of the patients. INTERPRETATION AND CONCLUSIONS: The results suggest that L1 is a rather safe drug which decreases iron overload without causing any considerable side-effects in Greek thalassemics.

Growth velocity monitoring of the efficacy of different therapeutic protocols in a group of thalassaemic children.

Since intensive chelating therapy for thalassaemic children was introduced, growth rates appear to have diminished. To investigate what factors were responsible we compared velocities of growth in length over a period of 1 year between groups distinguished by different strategies of treatment. Forty-two thalassaemic patients, 30 males aged 4-12 years, and 12 females, 4-10 years old, were assigned from their current treatment into subgroups based upon blood ferritin levels, daily dose of desferrioxamine and urinary zinc levels. CONCLUSION The results confirm that a reduction in desferrioxamine results in greater growth. If blood ferritin is low, the change effect may be greater. Secondly, any zinc deficiency should be treated. The changes in treatment convert a growth velocity of -2 to -3 SDS to a velocity of about -1 SDS.

Update on thalassemia.

Many advances in the understanding and management of the thalassemia syndromes have been made during the past several years. Our knowledge of normal globin gene function and of the consequences of specific mutations has been advanced by identification of the genetic defects causing thalassemia. Prenatal diagnosis is now possible with molecular biology technology. Standards have been established for transfusion, splenectomy, prevention of postsplenectomy infection, and effective iron chelation therapy. Bone marrow transplantation is now available for those with a compatible familial donor. Research efforts currently are directed toward safer blood products, oral iron chelators, and improved understanding of the developmental regulation of globin gene expression for effective gene transfer.

[Growth velocity in thalassemic children receiving different protocols of chelating therapy]. / Velocità di crescita dei bambini talassemici sottoposti a diversi protocolli di terapia chelante.

The aim of this study was to compare growth velocity in thalassemic children using two different treatment protocols. Thalassemic children were initially treated with high daily doses of desferrioxamine, obtaining a good rate of initial growth which then unexpectedly slowed down later. The introduction of a new treatment protocol reducing both the dose and frequency with which the drug was administered provoked a significant increase in the rate of growth greater than that observed in the group treated using the previous protocol.

Pituitary function in thalassemic patients and the effect of chelation therapy.

This study examined anterior pituitary function and the effect of chelation therapy in 31 patients with beta-thalassemia/HbE disease. Patients were divided into those receiving chelation therapy by deferoxamine and those receiving no such therapy (control group). Pituitary function studies were repeated in both groups 18 months later. The results showed decreased pituitary responses following stimulation in 22 patients. Among these, gonadotropin and PRL responses were most affected. After 18 months, serum ferritin levels had significantly decreased in the deferoxamine group. PRL and GH responses were improved in 3 patients receiving chelation therapy without changes in other hormone responses. In contrast, no changes in pituitary responses were shown in the control group at the end of follow-up. There were 6 drop-outs (4 in the control and 2 in the deferoxamine group) and 3 deaths (2 in the control and 1 in the deferoxamine group) during 18 months. In conclusion, gonadotropin and PRL deficiencies occur most frequently in thalassemic patients. Chelation therapy for 18 months markedly reduced serum ferritin level and might preserve or improve PRL and GH secretions, but seems to have no beneficial effects on other pituitary hormone reserves.