Despite recent advances in understanding the pathophysiologic mechanisms behind the thalassemia intermedia (TI) phenotype, data on the effects of treatment are deficient. To provide such data, we evaluated 584 TI patients for the associations between patient and disease characteristics, treatment received, and the rate of complications. The most common disease-related complications were osteoporosis, extramedullary hematopoeisis (EMH), hypogonadism, and cholelithiasis, followed by thrombosis, pulmonary hypertension (PHT), abnormal liver function, and leg ulcers. Hypothyroidism, heart failure, and diabetes mellitus were less frequently observed. On multivariate analysis, older age and splenectomy were independently associated with an increased risk of most disease-related complications. Transfusion therapy was protective for thrombosis, EMH, PHT, heart failure, cholelithiasis, and leg ulcers. However, transfusion therapy was associated with an increased risk of endocrinopathy. Iron chelation therapy was in turn protective for endocrinopathy and PHT. Hydroxyurea treatment was associated with an increased risk of hypogonadism yet was protective for EMH, PHT, leg ulcers, hypothyroidism, and osteoporosis. Attention should be paid to the impact of age on complications in TI, and the beneficial role of splenectomy deserves revisiting. This study provides evidence that calls for prospective evaluation of the roles of transfusion, iron chelation, and hydroxyurea therapy in
BackgroundHaemoglobinopathies constitute the commonest recessive monogenic disorders worldwide, and the treatment of affected individuals presents a substantial global disease burden. β-thalassaemia is characterised by the reduced synthesis (β+) or absence (βo) of the β-globin chains in the HbA molecule, resulting in accumulation of excess unbound α-globin chains that precipitate in erythroid precursors in the bone marrow and in the mature erythrocytes, leading to ineffective erythropoiesis and peripheral haemolysis. Approximately 1.5% of the global population are heterozygotes (carriers) of the β-thalassemias; there is a high incidence in populations from the Mediterranean basin, throughout the Middle East, the Indian subcontinent, Southeast Asia, and Melanesia to the Pacific Islands.AimThe principal aim of this paper is to review, from a historical standpoint, our knowledge about an ancient disease, the β-thalassemias, and in particular, when, how and in what way β-thalassemia spread worldwide to reach such high incidences in certain populations.ResultsMutations involving the β-globin gene are the most common cause of genetic disorders in humans. To date, more than 350 β-thalassaemia mutations have been reported. Considering the current distribution of β- thalassemia, the wide diversity of mutations and the small number of specific mutations in individual populations, it seems unlikely that β-thalassemia originated in a single place and time.ConclusionsVarious processes are known to determine the frequency of genetic disease in human populations. However, it is almost impossible to decide to what extent each process is responsible for the presence of a particular genetic disease. The wide spectrum of β-thalassemia mutations could well be explained by looking at their geographical distribution, the history of malaria, wars, invasions, mass migrations, consanguinity, and settlements. An analysis of the distribution of the molecular spectrum of haemoglobinopathies allows for the development and improvement of diagnostic tests and management of these disorders.
Objective:Many patients with transfusional iron overload are at risk for progressive organ dysfunction and early death and poor compliance with older chelation therapies is believed to be a major contributing factor. Phase II/III studies have shown that oral deferasirox 20–30 mg/kg/d reduces iron burden, depending on transfusional iron intake.Methods:The prospective, open-label, 1-yr ESCALATOR study in the Middle East was designed to evaluate once-daily deferasirox in patients ≥2 yr with β-thalassaemia major and iron overload who were previously chelated with deferoxamine and/or deferiprone. Most patients began treatment with deferasirox 20 mg/kg/d; doses were adjusted in response to markers of over- or under-chelation. The primary endpoint was treatment success, defined as a reduction in liver iron concentration (LIC) of ≥3 mg Fe/g dry weight (dw) if baseline LIC was ≥10 mg Fe/g dw, or final LIC of 1–7 mg Fe/g dw for patients with baseline LIC of 2 to <10 mg Fe/g dw.Results:Overall, 233/237 enrolled patients completed 1 yr’s treatment. Mean baseline LIC was 18.0 ± 9.1 mg Fe/g dw, while median serum ferritin was 3356 ng/mL. After 1 yr’s deferasirox treatment, the intent-to-treat population experienced a significant treatment success rate of 57.0% (P = 0.016) and a mean reduction in LIC of 3.4 mg Fe/g dw. Changes in serum ferritin appeared to parallel dose increases at around 24 wk. Most patients (78.1%) underwent dose increases above 20 mg/kg/d, primarily to 30 mg/kg/d. Drug-related adverse events were mostly mild to moderate and resolved without discontinuing treatment.Conclusions:The results of the ESCALATOR study in primarily heavily iron-overloaded patients confirm previous observations in patients with β-thalassaemia, highlighting the importance of timely deferasirox dose adjustments based on serum ferritin levels and transfusional iron intake to ensure patients achieve their therapeutic goal of maintenance or reduction in iron burden.
The aim of our study was to assess the cytokine profile of sickle cell disease (SCD) patients in steady state and in vaso-occlusive crisis (VOC). VOC has a complex nature, involving interactions between sickle red blood cells (RBC), the endothelium, and leucocytes. Endothelial damage due to recurrent adhesion of sickle RBCs may disrupt endothelial function, leading to altered cytokine release. It is therefore pertinent to study the cytokine profile of SCD patients in steady state and in crisis prior to exploring its contribution to vasoocclusive manifestations, since it is believed that an altered balance of proinflammatory and anti-inflammatory cytokines plays an important role in painful crisis. Cytokines including IL1b, IL-2, IL-4, IL-6, IL-8, TNF-a, and IFN-g were measured by commercially available ELISA kits in SCD patients (n = 60); in steady state (n = 26) and in painful crisis (n = 34) and compared with nonanemic age-and sex-matched normal Omani controls (n = 20). SCD patients in crisis showed elevated levels of TNF-a (P < 0.092) and IL-6 (P < 0.024) when compared with steady state. It was also observed that SCD patients in steady state showed a significant elevation in IL-1b (P < 0.04), IL-6 (P < 0.0001), and IFN-g (P < 0.02) as compared to normal subjects. It is thus evident that both type I and type II cytokines are significantly altered in SCD patients. In steady state, type II proinflammatory cytokines are elevated, whereas in crisis, an additional augmentation of type I cytokines occurs, with persistent elevation of type II cytokines, emphasizing the role of perturbed endothelium and activated monocytes in the pathophysiology of vaso-occlusion in sickle cell crisis. Am.
See also Mannucci PM. Red cells playing as activated platelets in thalassemia intermedia. This issue, pp 2149–51. Summary. Background: Hypercoagulability in splenectomized patients with thalassemia intermedia (TI) has been extensively evaluated. However, clinical and laboratory characteristics of patients who eventually develop overt thromboembolic events (TEE) are poorly studied. Patients/Methods: Three Groups of TI patients (n = 73 each) were retrospectively identified from a registry involving six centers across the Middle East and Italy: Group I, all splenectomized patients with a documented TEE; Group II, age‐ and sex‐matched splenectomized patients without TEE; and Group III, age‐ and sex‐matched non‐splenectomized patients without TEE. Retrieved data included demographics, laboratory parameters, clinical complications, and received treatments that may influence TEE development, and reflected the period prior to TEE occurrence in Group I. Results: The mean age of Group I patients at development of TEE was 33.1 ± 11.7 years, with a male to female ratio of 33:40. TEE were predominantly venous (95%) while four patients (5%) had documented stroke. Among studied parameters, Group I patients were more likely to have a nucleated red blood cell (NRBC) count ≥ 300 × 106 L−1, a platelet count ≥ 500 × 109 L−1 and evidence of pulmonary hypertension (PHT), or be transfusion naïve. The median time to thrombosis following splenectomy was 8 years. Patients with an NRBC count ≥ 300 × 106 L−1, a platelet count ≥ 500 × 109 L−1, or who were transfusion naive also had a shorter time to thrombosis following splenectomy. Conclusion: Splenectomized TI patients who will develop TEE may be identified early on by high NRBC and platelet counts, evidence of PHT, and transfusion naivety.
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