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1.
Acta Haematol ; 147(4): 427-434, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38104534

RESUMO

BACKGROUND: Most patients with lower risk myelodysplastic neoplasms or syndromes (MDSs) become RBC transfusion-dependent, resulting in iron overload, which is associated with an increased oxidative stress state. Iron-chelation therapy is applied to attenuate the toxic effects of this state. Deferiprone (DFP) is an oral iron chelator, which is not commonly used in this patient population, due to safety concerns, mainly agranulocytosis. The purpose of this study was to assess the effect of DFP, on oxidative stress parameters in iron-overloaded RBC transfusion-dependent patients with lower risk MDSs. METHODS: Adult lower risk MDS patients with a cumulative transfusion burden of >20 red blood cell units and evidence of iron overload (serum ferritin >1,000 ng/mL) were included in this study. DFP was administered (100 mg/kg/day) for 4 months. Blood samples for oxidative stress parameters and iron overload parameters were done at baseline and monthly: reactive oxygen species (ROS), phosphatidylserine, reduced glutathione, membrane lipid peroxidation, serum ferritin, and cellular labile iron pool. The primary efficacy variable was ROS. Tolerability and side effects were recorded as well. A paired t test was applied for statistical analyses. RESULTS: Eighteen patients were treated with DFP. ROS significantly decreased in all cell lineages: median decrease of 58.6% in RBC, 33.3% in PMN, and 39.8% in platelets (p < 0.01 for all). Other oxidative stress markers improved: phosphatidylserine decreased by 57.95%, lipid peroxidase decreased by 141.3%, and reduced gluthathione increased by 72.8% (p < 0.01 for all). The iron-overload marker and cellular labile iron pool decreased by 35% in RBCs, 44.3% in PMN, and 46.3% in platelets (p < 0.01 for all). No significant changes were observed in SF levels. There were no events of agranulocytosis. All AEs were grades 1-2. CONCLUSIONS: Herein, we showed preliminary evidence that DFP decreases iron-induced oxidative stress in MDS patients with a good tolerability profile (albeit a short follow-up period). No cases of severe neutropenia or agranulocytosis were reported. The future challenge is to prove that reduction in iron toxicity will eventually be translated into a clinically meaningful improvement.


Assuntos
Deferiprona , Quelantes de Ferro , Sobrecarga de Ferro , Síndromes Mielodisplásicas , Estresse Oxidativo , Humanos , Deferiprona/uso terapêutico , Deferiprona/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Quelantes de Ferro/uso terapêutico , Quelantes de Ferro/farmacologia , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/metabolismo , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Piridonas/uso terapêutico , Piridonas/efeitos adversos , Piridonas/administração & dosagem , Idoso de 80 Anos ou mais , Adulto , Israel , Administração Oral , Espécies Reativas de Oxigênio/metabolismo , Transfusão de Eritrócitos , Ferritinas/sangue
2.
Mol Pharm ; 20(1): 481-490, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36378830

RESUMO

Deferoxamine (DFO) is an effective FDA-approved iron chelator. However, its use is considerably limited by off-target toxicities and an extremely cumbersome dose regimen with daily infusions. The recent development of a deferoxamine-based nanochelator (DFO-NP) with selective renal excretion has shown promise in ameliorating animal models of iron overload with a substantially improved safety profile. To further the preclinical development of this promising nanochelator and to inform on the feasibility of clinical development, it is necessary to fully characterize the dose and administration-route-dependent pharmacokinetics and to develop predictive pharmacokinetic (PK) models describing absorption and disposition. Herein, we have evaluated the absorption, distribution, and elimination of DFO-NPs after intravenous and subcutaneous (SC) injection at therapeutically relevant doses in Sprague Dawley rats. We also characterized compartment-based model structures and identified model-based parameters to quantitatively describe the PK of DFO-NPs. Our modeling efforts confirmed that disposition could be described using a three-compartment mamillary model with elimination and saturable reabsorption both occurring from the third compartment. We also determined that absorption was nonlinear and best described by parallel saturable and first-order processes. Finally, we characterized a novel pathway for saturable SC absorption of an ultrasmall organic nanoparticle directly into the systemic circulation, which offers a novel strategy for improving drug exposure for nanotherapeutics.


Assuntos
Desferroxamina , Sobrecarga de Ferro , Ratos , Animais , Ratos Sprague-Dawley , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/metabolismo , Quelantes/uso terapêutico
3.
Int J Mol Sci ; 24(23)2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-38069073

RESUMO

The design of clinical protocols and the selection of drugs with appropriate posology are critical parameters for therapeutic outcomes. Optimal therapeutic protocols could ideally be designed in all diseases including for millions of patients affected by excess iron deposition (EID) toxicity based on personalised medicine parameters, as well as many variations and limitations. EID is an adverse prognostic factor for all diseases and especially for millions of chronically red-blood-cell-transfused patients. Differences in iron chelation therapy posology cause disappointing results in neurodegenerative diseases at low doses, but lifesaving outcomes in thalassemia major (TM) when using higher doses. In particular, the transformation of TM from a fatal to a chronic disease has been achieved using effective doses of oral deferiprone (L1), which improved compliance and cleared excess toxic iron from the heart associated with increased mortality in TM. Furthermore, effective L1 and L1/deferoxamine combination posology resulted in the complete elimination of EID and the maintenance of normal iron store levels in TM. The selection of effective chelation protocols has been monitored by MRI T2* diagnosis for EID levels in different organs. Millions of other iron-loaded patients with sickle cell anemia, myelodysplasia and haemopoietic stem cell transplantation, or non-iron-loaded categories with EID in different organs could also benefit from such chelation therapy advances. Drawbacks of chelation therapy include drug toxicity in some patients and also the wide use of suboptimal chelation protocols, resulting in ineffective therapies. Drug metabolic effects, and interactions with other metals, drugs and dietary molecules also affected iron chelation therapy. Drug selection and the identification of effective or optimal dose protocols are essential for positive therapeutic outcomes in the use of chelating drugs in TM and other iron-loaded and non-iron-loaded conditions, as well as general iron toxicity.


Assuntos
Sobrecarga de Ferro , Talassemia beta , Humanos , Deferiprona/uso terapêutico , Desferroxamina/uso terapêutico , Piridonas/efeitos adversos , Quelantes de Ferro/efeitos adversos , Sobrecarga de Ferro/etiologia , Sobrecarga de Ferro/induzido quimicamente , Terapia por Quelação/métodos , Ferro/metabolismo , Talassemia beta/tratamento farmacológico , Talassemia beta/complicações , Quimioterapia Combinada
4.
Clin Pract Epidemiol Ment Health ; 19(Suppl-1): e174501792301031, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38659631

RESUMO

Background: ß-Thalassemia major (ß-TM) represents one of the most important hemoglobinopathies worldwide. Remarkable improvements have been achieved in supportive therapy based on blood transfusions and iron chelation, and nowadays, this approach is capable of assuring a long life in these patients in industrialized countries. The only curative treatment is represented by hematopoietic stem cell transplantation (HSCT). However, this treatment may be burdened by deterioration in the Health-Related Quality of Life (HRQoL). This paper aimed to evaluate the role of HRQoL in transplanted ß-TM patients with a systematic review and meta-analysis. Methods: PubMed database, Web of Science, and Scopus were systematically searched for studies published between January 1st, 2000 to September 2020. The following terms were entered in the database queries: ß-thalassemia, HRQoL, and HSCT. The study was carried out according to the Preferred Reporting Items for Systematic and Meta-analyses (PRISMA) statement. Results: We identified a total of 33 potential studies. Among these, 10 were finally considered in the systematic review and 5 in the meta-analysis. Overall, good scores in the principal domains of HRQoL were reported by transplanted patients. These data were confirmed by results of meta-analysis that showed significant difference between transplanted and ß-TM patients treated with conventional therapy in the physical and emotional dimension, with a medium effect size [d=0.65, 95% CI (0.29-1.02), z = 3.52, p =0.0004, I2=75%; and d=0.59, 95% CI (0.43-0.76), z = 6.99, p <0.00001, I2=0%, respectively]. Conclusion: HRQoL is generally good in ß-TM transplanted patients and may significantly contribute in deciding whether or not to transplant a ß-TM patient treated with conventional therapy.

5.
Haemophilia ; 28(5): 865-871, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35732067

RESUMO

AIM: This study aims to determine the potential causative elements which are responsible for the cartilage damage in case of frequent intra-articular bleeding and to evaluate the effects of intra-articular free iron and chelation of iron in the knee joint. METHODS: Thirty-five New Zealand rabbits were randomly divided into five groups according to substances injected into their knee joints. Plasma (group I) and cellular components (group II) of the blood harvested from the rabbits, iron (ferric hydroxide sucrose) (group III), iron&chelator (group IV) and only chelator (deferoxamine mesylate) (group V) were injected into their right knees three times a week for 12 weeks. The joint surface was examined histologically according to the classification system modified from Colombo et al. The changes in the synovial tissue were evaluated according to the scoring system modified from Madhok et al. RESULTS: Cartilage and synovial abnormality scores were significantly higher in all study groups when compared to their own controls (p < 0.0001). Cartilage scores of groups I and V were significantly lower when compared to groups III and IV (p = 0.002 for group I and p = 0.003 for group V). Synovial abnormality score of group I was significantly lower than scores of groups III and IV (p = 0.001); and of group V lower than groups III and IV (p = 0.003 and p = 0.001, respectively). CONCLUSIONS: All substances tested in this study caused a certain amount of damage in the cartilage tissue and led to synovial abnormalities. Both iron and iron&chelator caused more damage in the cartilage and led to more advanced synovial changes when compared to the plasma component of blood and chelator itself. Influence of iron and iron&chelators were found to be similar showing that chelation was inadequate in antagonizing the detrimental effects of iron.


Assuntos
Cartilagem Articular , Animais , Coelhos , Quelantes/farmacologia , Injeções Intra-Articulares , Ferro , Articulação do Joelho/patologia , Membrana Sinovial/patologia
6.
Transfus Apher Sci ; 61(2): 103319, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34801431

RESUMO

BACKGROUND: In transfusion-related iron overload, haem-derived iron accumulation in monocytes/macrophages is the initial event. When iron loading exceeds the ferritin storage capacity, iron is released into the plasma. When iron loading exceeds transferrin binding capacity, labile, non-transferrin-bound iron (NTBI) appears and causes organ injury. Haemin-induced cell death has already been investigated; however, whether NTBI induces cell death in monocytes/macrophages remains unclear. MATERIAL AND METHODS: Human monocytic THP-1 cells were treated with haemin or NTBI, particularly ferric ammonium citrate (FAC) or ferrous ammonium sulfate (FAS). The intracellular labile iron pool (LIP) was measured using an iron-sensitive fluorescent probe. Ferritin expression was measured by western blotting. RESULTS: LIP was elevated after haemin treatment but not after FAC or FAS treatment. Reactive oxygen species (ROS) generation and cell death induction were remarkable after haemin treatment but not after FAC or FAS treatment. Ferritin expression was not different between the FAC and haemin treatments. The combination of an iron chelator and a ferroptosis inhibitor significantly augmented the suppression of haemin cytotoxicity (p = 0.011). DISCUSSION: The difference in LIP suggests the different iron traffic mechanisms for haem-derived iron and NTBI. The Combination of iron chelators and antioxidants is beneficial for iron overload therapy.


Assuntos
Sobrecarga de Ferro , Ferro , Morte Celular , Ferritinas , Hemina/farmacologia , Humanos , Ferro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transferrina/metabolismo , Transferrina/farmacologia
7.
J Clin Pharm Ther ; 47(10): 1619-1626, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35748618

RESUMO

WHAT IS KNOWN AND OBJECTIVE: Patients with low-risk myelodysplastic syndrome (MDS) and aplastic anaemia (AA) often need transfusions, which may accelerate iron overload. The aim of this study was to evaluate the efficacy, safety and dose-effect relationships of deferasirox (DFX) in patients with low-risk MDS and AA who were refractory to regular treatment in a real-world setting. METHODS: Patient data were recorded, and dose-effect relationships of DFX were calculated after the first 6 months. Total annual exposure to DFX was calculated after 12 months and expressed as the accumulated exposure time at a dosage of 20 mg/kg/day. RESULTS AND DISCUSSION: Sixty-one patients with low-risk MDS and 51 with AA were enrolled. The minimum dosage of DFX needed for a significant serum ferritin (SF) decrease was 20 mg/kg/day at 6 months, and the minimum accumulation of DFX had to reach 9 months at 20 mg/kg/day by 12 months for patients with low-risk MDS. For patients with AA, the minimum dosage was 10 mg/kg/day at 6 months, and the minimum accumulation had to reach 3 months at 20 mg/kg/day by 12 months. With the same exposure, significant improvements in haematological parameters were also observed in AA. Lower liver enzymes compared with baseline were observed. Gastrointestinal disorders and elevated serum creatinine were the most common side effects. Higher exposure to DFX correlated with longer overall survival (OS). WHAT IS NEW AND CONCLUSION: A significant decrease in SF and an improvement in haematologic parameters, organ function and even OS can be achieved if the accumulated DFX dose reaches a certain level. Patients with low-risk MDS need a higher dose than those with AA.


Assuntos
Anemia Aplástica , Sobrecarga de Ferro , Síndromes Mielodisplásicas , Anemia Aplástica/tratamento farmacológico , Benzoatos/efeitos adversos , Creatinina , Deferasirox/uso terapêutico , Ferritinas/uso terapêutico , Humanos , Quelantes de Ferro/efeitos adversos , Sobrecarga de Ferro/tratamento farmacológico , Síndromes Mielodisplásicas/tratamento farmacológico , Triazóis/efeitos adversos
8.
Hemoglobin ; 46(4): 201-213, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35930250

RESUMO

Iron chelation therapy (ICT) is essential to prevent complications of iron overload in patients with transfusion-dependent thalassemia. However, the role that adherence to ICT plays in health-related outcomes is less well known. Our objectives were to identify adherence rates of ICT, and to assess methods of measurement, predictors of adherence, and adherence-related health outcomes in the literature published between 1980 and 2020. Of 543 articles, 43 met the inclusion criteria. Studies measured ICT adherence, predictors, and/or outcomes associated with adherence. Most studies were across multiple countries in Europe and North America (n = 8/43, 18.6%), recruited in clinics (n = 39/43, 90.7%), and focused on ß-thalassemia (ß-thal) (n = 25/43, 58.1%). Common methods of assessing ICT adherence included patient self-report (n = 24/43, 55.8%), pill count (n = 9/43, 20.9%), prescription refill history (n = 3/43, 7.0%), provider scoring (n = 3/43, 7.0%), and combinations of methods (n = 4/43, 9.3%). Studies reported adherence either in 'categories' with different levels of adherence (n = 24) or 'quantitatively' as a percentage of doses of medication taken out of those prescribed (n = 17). Adherence levels varied (median 91.7%, range 42.0-99.97%). Studies varied in sample size and methods of adherence assessment and reporting, which prohibited meta-analysis. Due to a lack of consensus on how adherence is defined, it is difficult to compare ICT adherence reporting. Further research is needed to establish guidelines for assessing adherence and identifying suboptimal adherence. Behavioral digital interventions have the potential to optimize ICT adherence and health outcomes.


Assuntos
Sobrecarga de Ferro , Talassemia , Talassemia beta , Adulto , Humanos , Talassemia beta/complicações , Talassemia beta/tratamento farmacológico , Terapia por Quelação/efeitos adversos , Ferro , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Adesão à Medicação , Talassemia/complicações , Talassemia/tratamento farmacológico
9.
Hemoglobin ; 46(2): 114-117, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36069257

RESUMO

Red blood cell (RBC) transfusions have been established as one of the primary therapies in treating sickle cell anemia. However, they are not free of side effects, with overloading the body with iron being one of the most important. Iron chelation therapy greatly reduces the iron load of the body. In addition, hydroxyurea (HU), an oral chemotherapeutic drug also has a significant role in the treatment of the disease with beneficial effects on many of the clinical problems that arise, mainly in reducing painful crises. The aim of this study was to investigate the effect of synergistic transfusion therapy and HU on the response to deferasirox (DFX) chelation therapy. Eighteen patients with sickle cell disease were divided into two groups based on their treatment, either with simple transfusions and DFX or with a combination of transfusion therapy, DFX and HU, and were evaluated with magnetic resonance imaging (MRI) for liver iron concentration (LIC) and biochemistry. All patients completed the study. The results of the study showed improvement in serum ferritin (FER) levels and LIC after 12 months of therapy in both groups, especially in the group receiving the combination therapy with HU. In addition, there was a noteworthy improvement in serum glutamic-oxaloacetic transaminase (SGOT), serum glutamic pyruvic transaminase (SGPT) and lactate dehydrogenase (LDH) levels with serum creatinine (Cr) levels remaining stable during the study in both groups. Hydroxyurea, when combined with iron chelators such as DFX, provides an additional benefit of iron chelation in patients receiving chronic transfusion therapy.


Assuntos
Anemia Falciforme , Quelantes de Ferro , Sobrecarga de Ferro , Alanina Transaminase/uso terapêutico , Anemia Falciforme/complicações , Anemia Falciforme/terapia , Aspartato Aminotransferases/uso terapêutico , Terapia por Quelação , Creatinina/uso terapêutico , Deferasirox/uso terapêutico , Ferritinas , Humanos , Hidroxiureia/uso terapêutico , Ferro , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Lactato Desidrogenases
10.
Int J Mol Sci ; 23(17)2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36077584

RESUMO

Thalassemia is the most common genetic disorder worldwide. Thalassemia intermedia (TI) is non-transfusion-dependent thalassemia (NTDT), which includes ß-TI hemoglobin, E/ß-thalassemia and hemoglobin H (HbH) disease. Due to the availability of iron chelation therapy, the life expectancy of thalassemia major (TM) patients is now close to that of TI patients. Iron overload is noted in TI due to the increasing iron absorption from the intestine. Questions are raised regarding the relationship between iron chelation therapy and decreased patient morbidity/mortality, as well as the starting threshold for chelation therapy. Searching all the available articles up to 12 August 2022, iron-chelation-related TI was reviewed. In addition to splenectomized patients, osteoporosis was the most common morbidity among TI cases. Most study designs related to ferritin level and morbidities were cross-sectional and most were from the same Italian study groups. Intervention studies of iron chelation therapy included a subgroup of TI that required regular transfusion. Liver iron concentration (LIC) ≥ 5 mg/g/dw measured by MRI and ferritin level > 300 ng/mL were suggested as indicators to start iron chelation therapy, and iron chelation therapy was suggested to be stopped at a ferritin level ≤ 300 ng/mL. No studies showed improved overall survival rates by iron chelation therapy. TI morbidities and mortalities cannot be explained by iron overload alone. Hypoxemia and hemolysis may play a role. Head-to-head studies comparing different treatment methods, including hydroxyurea, fetal hemoglobin-inducing agents, hypertransfusion as well as iron chelation therapy are needed for TI, hopefully separating ß-TI and HbH disease. In addition, the target hemoglobin level should be determined for ß-TI and HbH disease.


Assuntos
Sobrecarga de Ferro , Talassemia alfa , Talassemia beta , Ferritinas , Humanos , Ferro/metabolismo , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Talassemia beta/genética , Talassemia beta/terapia
11.
Medicina (Kaunas) ; 58(10)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36295656

RESUMO

Non-transfusion-dependent thalassemia (NTDT) has been considered less severe than its transfusion-dependent variants. The most common forms of NTDT include ß-thalassemia intermedia, hemoglobin E/beta thalassemia, and hemoglobin H disease. Patients with NTDT develop several clinical complications, despite their regular transfusion independence. Ineffective erythropoiesis, iron overload, and hypercoagulability are pathophysiological factors that lead to morbidities in these patients. Therefore, an early and accurate diagnosis of NTDT is essential to ascertaining early interventions. Currently, several conventional management options are available, with guidelines suggested by the Thalassemia International Federation, and novel therapies are being developed in light of the advancement of the understanding of this disease. This review aimed to increase clinicians' awareness of NTDT, from its basic medical definition and genetics to its pathophysiology. Specific complications to NTDT were reviewed, along with the risk factors for its development. The indications of different therapeutic options were outlined, and recent advancements were reviewed.


Assuntos
Sobrecarga de Ferro , Talassemia , Humanos , Transfusão de Sangue , Hemoglobina E/uso terapêutico , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/etiologia , Sobrecarga de Ferro/diagnóstico , Sobrecarga de Ferro/tratamento farmacológico , Talassemia/complicações , Talassemia/terapia , Talassemia/diagnóstico
12.
Ann Hematol ; 100(2): 455-463, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33159566

RESUMO

The European Leukemia Net (ELN) guidelines for treatment of myelodysplastic syndromes (MDS) connect heterogeneous MDS subgroups with a number of therapeutic options ranging from best supportive care to allogeneic stem cell transplantation (alloSCT). However, it is currently unknown whether adherence to guideline recommendations translates into improved survival. The sizeable database of the Duesseldorf MDS Registry allowed us to address this question. We first performed a retrospective analysis including 1698 patients (cohort 1) to whom we retrospectively applied the ELN guidelines. We compared patients treated according to the guidelines with patients who deviated from it, either because they received a certain treatment though it was not recommended or because they did not receive that treatment despite being eligible. We also performed a prospective study with 381 patients (cohort 2) who were seen in our department and received guideline-based expert advice. Again, we compared the impact of subsequent guideline-adherent versus non-adherent treatment. For the majority of treatment options (best supportive care, lenalidomide, hypomethylating agents, low-dose chemotherapy, and intensive chemotherapy), we found that adherence to the ELN guidelines did not improve survival in cohort 1. The same was true when patient management was prospectively enhanced through guideline-based treatment advice given by MDS experts (cohort 2). The only exceptions were alloSCT and iron chelation (ICT). Patients receiving ICT and alloSCT as recommended fared significantly better than those who were eligible but received other treatment. Our analysis underscores the limited survival impact of most MDS therapies and suggests to pursue alloSCT in all suitable candidates. Graphical abstract.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Bases de Dados Factuais , Fidelidade a Diretrizes , Transplante de Células-Tronco Hematopoéticas , Síndromes Mielodisplásicas , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Síndromes Mielodisplásicas/mortalidade , Síndromes Mielodisplásicas/terapia , Estudos Prospectivos , Estudos Retrospectivos , Taxa de Sobrevida , Transplante Homólogo
13.
Qual Life Res ; 30(2): 467-477, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32920766

RESUMO

PURPOSE: To evaluate health-related quality of life (HRQoL) and satisfaction with iron chelation therapy (ICT) of patients with transfusion-dependent ß-thalassemia (TDT) managed under routine care conditions. PATIENTS AND METHODS: This was an observational, multicenter, cross-sectional study conducted in three hospital-based Thalassemia Units of Western Greece. Patients confidentially completed the 36-item short-form (SF-36) and the "satisfaction with ICT" (SICT) instruments to assess HRQoL and ICT satisfaction respectively. RESULTS: One hundred and thirty-one adult TDT patients [74 female, median (IQR) age: 41 (36-47) years] were enrolled. Eighty patients (61.1%) were receiving parenteral ICT, with or without oral chelators (Group I), whereas 51 (38.9%) were only receiving oral ICT (Group II). The median SF-36 physical component summary and mental component summary scores were 76.3 and 75.7 among Group I, and 76.9 and 74.5 among Group II patients, not differing between the two groups. In their majority, Group I (84.6%) and Group II (92.9%) patients reported preferring oral ICT. Moreover, Group I patients reported greater perceived ICT effectiveness (median SICT score: 4.3 versus 4.2; p = 0.039), whereas patients receiving deferasirox-containing ICT reported higher treatment acceptance (median SICT score: 4.0 versus 3.6, p = 0.038) and greater satisfaction with the burden of their ICT (median SICT score: 4.4 versus 3.9, p = 0.033). CONCLUSION: TDT patients prefer to receive oral ICT and are more satisfied of the burden of deferasirox-containing ICT, even though those receiving parenteral ICT are more satisfied by the effectiveness of their treatment. No differences in HRQoL were not noted between patients receiving parenteral versus oral ICT.


Assuntos
Quelantes de Ferro/uso terapêutico , Talassemia beta/tratamento farmacológico , Adulto , Estudos Transversais , Feminino , Grécia , Humanos , Quelantes de Ferro/administração & dosagem , Masculino , Satisfação do Paciente , Qualidade de Vida/psicologia
14.
BMC Nephrol ; 22(1): 418, 2021 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-34930156

RESUMO

BACKGROUND: Renal injury in transfusion dependent ß thalassemia patients (TDT) has been attributed to iron overload, chronic anemia and iron-chelation therapy (ICT) toxicity. We studied renal function in TDT patients treated with two different ICT regimes. PATIENTS AND METHODS: We studied 36 TDT patients: 26 received deferasirox (DFX) and 10 were treated with deferoxamine (DFO) +/- deferiprone (DFP). RESULTS: Increased uNAG was found in 30% of the DFX group vs. 10% of the DFO+/-DFP group, the mean uNAG level in the DFX group was significantly higher than in the DFO+/-DFP group, (P < 0.05). A moderate negative correlation was found between uNAG levels and mean serum ferritin for the prior 10 years (P = 0.03), more pronounced for the DFO+/-DFP group. Twenty nine patients had had their renal function evaluated 10 years earlier; eGFR significantly declined in patients switched to DFX (P = 0.0093) but not in patients who continued DFO+/-DFP. CONCLUSIONS: A high prevalence of renal tubular damage was observed in our TDT patients, particularly those treated with DFX; uNAG was negatively associated with mean 10-year serum ferritin, suggesting ICT's involvement in tubular injury. A significant decline in eGFR compared to a decade earlier was observed only in patients currently treated with DFX. Strict follow-up of renal function in TDT patients is warranted.


Assuntos
Deferasirox/uso terapêutico , Desferroxamina/uso terapêutico , Quelantes de Ferro/uso terapêutico , Rim/fisiopatologia , Talassemia beta/tratamento farmacológico , Talassemia beta/fisiopatologia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
15.
Hemoglobin ; 45(3): 171-174, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34102943

RESUMO

Transfusion-dependent thalassemia (TDT) patients require regular blood transfusions. The unavoidable consequence is iron overload. Iron chelation therapy is the mainstay of treatment, of which the favorable outcome depends mainly on adherence level. The aim of this study was to assess adherence to iron chelation therapy of TDT patients. A cross-sectional cohort of TDT patients were evaluated on their adherence to chelation therapy using the Thai version of Morisky Medication Adherence Scales (MMAS-8). A total of 70 patients (38 males, 32 females), with a median age of 10 years, were enrolled in the study. Sixteen patients (22.9%) and 54 patients (77.1%) were classified as high and medium-low adherence level groups. The raised serum ferritin value for 6 months previous to enrollment in the high adherence level group is lower than the medium-low adherence level group (276.4 vs. 413.0 ng/mL, p = 0.034, respectively). Factors impacted high adherence to iron chelation including younger age (p = 0.015) and deferasirox (DFX) administration (p = 0.025). The body weight and height in both groups were not statistically different. The most common obstacle to adherence was forgetfulness. The Thai version of MMAS-8 is a practical tool for evaluating adherence to chelation therapy in TDT patients. High adherence level of patients correlates with more controlled serum ferritin level. The younger age and once-daily dose chelation therapy are associated with better adherence.


Assuntos
Terapia por Quelação , Quelantes de Ferro , Sobrecarga de Ferro , Talassemia , Benzoatos/uso terapêutico , Criança , Estudos Transversais , Deferasirox/uso terapêutico , Feminino , Humanos , Ferro , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Masculino , Talassemia/tratamento farmacológico
16.
BMC Ophthalmol ; 20(1): 376, 2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-32962679

RESUMO

BACKGROUND: Ocular involvement may occur via several mechanisms in patients with transfusion-dependent ß-thalassemia (TDT) mainly chronic anemia, iron overload and iron chelator toxicity. We aimed to evaluate the frequency of abnormal ocular findings and their relationship with hematologic parameters in TDT patients. METHODS: In this cross-sectional study from January 2018 to January 2019, a total of 79 patients with TDT over the age of 18 who were on iron-chelation therapy (ICT) were consecutively investigated. All patients were registered at the Thalassemia Comprehensive Center affiliated with Shiraz University of Medical Sciences, Shiraz, Southern Iran. Complete ophthalmic examination was performed by an expert ophthalmologist. Clinical and hematologic parameters were collected from the patients´ medical records. RESULTS: The mean age ± standard deviation (SD) of the patients was 28.4 ± 5.6 years (range: 18-43). Twenty-four patients (30.4%) were male and 29 (36.7%) were splenectomized. The mean ± SD of the best-corrected visual acuity (VA) was 0.960 ± 0.086 decimal, (range: 0.6-1), 0.016 ± 0.046 logMar, (range: 0-0.2). The frequency of patients with VA > 0.1 logMar was 3 (3.8%). The mean intraocular pressure (IOP) was 14.88 ± 3.34 (6-25) mmHg. Fundus abnormalities were observed in 8 patients (10.1%), consisting of increased cup-disk ratio (3.8%), vessel tortuosity (2.5%), retinal pigment epithelium degeneration (2.5%), myelinated nerve fiber layer (1.3%), and internal limiting membrane wrinkling (1.3%). No significant association was observed between fundus abnormalities, VA, or IOP with hematologic parameters (P > 0.05). TDT patients with diabetes mellitus had significantly higher IOP (P = 0.010) but similar frequency of fundus abnormalities with non-diabetic patients (P > 0.05). CONCLUSIONS: The frequency of ocular abnormalities in our patients was lower than the previous reports. The frequency of fundus abnormalities were similar in diabetic and non-diabetic thalassemia patients indicating close monitoring and proper management of the disease and comorbidities in these patients.


Assuntos
Sobrecarga de Ferro , Talassemia , Talassemia beta , Adulto , Estudos Transversais , Feminino , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Talassemia beta/complicações , Talassemia beta/epidemiologia
17.
Int J Mol Sci ; 21(22)2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33233561

RESUMO

Thalassemia syndromes are characterized by the inability to produce normal hemoglobin. Ineffective erythropoiesis and red cell transfusions are sources of excess iron that the human organism is unable to remove. Iron that is not saturated by transferrin is a toxic agent that, in transfusion-dependent patients, leads to death from iron-induced cardiomyopathy in the second decade of life. The availability of effective iron chelators, advances in the understanding of the mechanism of iron toxicity and overloading, and the availability of noninvasive methods to monitor iron loading and unloading in the liver, heart, and pancreas have all significantly increased the survival of patients with thalassemia. Prolonged exposure to iron toxicity is involved in the development of endocrinopathy, osteoporosis, cirrhosis, renal failure, and malignant transformation. Now that survival has been dramatically improved, the challenge of iron chelation therapy is to prevent complications. The time has come to consider that the primary goal of chelation therapy is to avoid 24-h exposure to toxic iron and maintain body iron levels within the normal range, avoiding possible chelation-related damage. It is very important to minimize irreversible organ damage to prevent malignant transformation before complications set in and make patients ineligible for current and future curative therapies. In this clinical case-based review, we highlight particular aspects of the management of iron overload in patients with beta-thalassemia syndromes, focusing on our own experience in treating such patients. We review the pathophysiology of iron overload and the different ways to assess, quantify, and monitor it. We also discuss chelation strategies that can be used with currently available chelators, balancing the need to keep non-transferrin-bound iron levels to a minimum (zero) 24 h a day, 7 days a week and the risk of over-chelation.


Assuntos
Desferroxamina/administração & dosagem , Quelantes de Ferro/administração & dosagem , Sobrecarga de Ferro/tratamento farmacológico , Ferro/metabolismo , Reação Transfusional/complicações , Talassemia beta/terapia , Adulto , Transfusão de Sangue , Cardiomiopatias/sangue , Cardiomiopatias/etiologia , Cardiomiopatias/fisiopatologia , Cardiomiopatias/prevenção & controle , Terapia por Quelação/efeitos adversos , Terapia por Quelação/métodos , Desferroxamina/efeitos adversos , Monitoramento de Medicamentos/instrumentação , Monitoramento de Medicamentos/métodos , Feminino , Coração/efeitos dos fármacos , Coração/fisiopatologia , Humanos , Ferro/toxicidade , Quelantes de Ferro/efeitos adversos , Sobrecarga de Ferro/sangue , Sobrecarga de Ferro/complicações , Sobrecarga de Ferro/fisiopatologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Pâncreas/patologia , Transferrina/metabolismo , Reação Transfusional/sangue , Reação Transfusional/fisiopatologia , Talassemia beta/metabolismo , Talassemia beta/patologia
18.
Rinsho Ketsueki ; 61(9): 1205-1211, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-33162517

RESUMO

Frequent packed red blood cell (pRBC) transfusion can cause transfusional iron overload. Excess iron generates reactive oxygen species and provokes organ dysfunction. In lower-risk myelodysplastic syndrome (MDS), hyperferritinemia is known as one of the negative prognostic factors. Thus far, iron chelation therapy (ICT) is the only effective treatment for chronic iron overload induced by transfusion. Transfusional iron overload is diagnosed when serum ferritin (SF) levels are ≥500 ng/ml and cumulative volume of pRBC transfusion is ≥20 JPN units. ICT should be initiated when SF levels are ≥1,000 ng/ml and will be further continued until SF levels decline to <500 ng/ml. ICT serves to ameliorate organ dysfunction. A prospective study demonstrated that in patients with lower-risk MDS, ICT can reduce the risk of combined events, including cardiac events, hepatic events, AML transformation, and death of any cause. In some patients, hematological improvement will be observed. However, clinical features underling this hematological phenomenon are not fully understood. Therefore, ICT should not be performed solely for the purpose of hematological recovery.


Assuntos
Terapia por Quelação , Sobrecarga de Ferro , Reação Transfusional , Transfusão de Sangue , Humanos , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/etiologia , Sobrecarga de Ferro/terapia , Estudos Prospectivos , Reação Transfusional/terapia
19.
Blood Cells Mol Dis ; 77: 67-71, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30978615

RESUMO

BACKGROUND: In patients with thalassemia major, examination routinely used for the evaluation of iron load in Indonesia is serum ferritin, but it is strongly influenced by other factors such as infections, inflammation and vitamin C levels. Evaluation of urinary iron excretion is an important and easy method to indicate iron chelation efficacy. OBJECTIVE: To determine the efficacy of iron chelation therapy by urinary iron examination and to evaluate its correlation with the time of transfusion, serum ferritin level, transferrin saturation and T2* MRI. METHODS: Prospective cohort study was conducted in children with thalassemia major aged 7-<18 years old who received DFP therapy. Twenty-four-hour urine collections were examined through inductively coupled plasma - mass spectrometry (ICP-MS). Patient's serum ferritin, transferrin saturation, peripheral blood, differential count and T2* MRI was documented during the study. Data analysis is based on urine iron level, body iron balance and the correlation between urine iron level, serum ferritin, transferrin saturation and T2* MRI and dosage of DFP. RESULTS: Thirty (55%) subjects showed a higher urine iron level on the day prior to transfusion (mean: 12,828 SD ±12,801 µg/24 h) in comparison to post transfusion (mean: 10,985 SD ±10,023 µg/24 h). All subjects had positive iron balance (mean 524 SD ±230 mg). There were positive correlation between urine iron level and transferrin saturation (r = 0.559, p = 0.01) and serum ferritin (r = 0.291, p = 0.03), no correlation found with T2* MRI results. CONCLUSIONS: There is a relationship to urinary iron excretion in response to chelation therapy and the degree of iron load.


Assuntos
Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/urina , Ferro/urina , Talassemia beta/complicações , Adolescente , Biomarcadores , Transfusão de Sangue , Terapia por Quelação , Criança , Feminino , Ferritinas/sangue , Humanos , Quelantes de Ferro/farmacologia , Sobrecarga de Ferro/diagnóstico , Sobrecarga de Ferro/etiologia , Imageamento por Ressonância Magnética , Masculino , Resultado do Tratamento , Urinálise , Talassemia beta/terapia
20.
Ann Hematol ; 98(2): 339-350, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30413901

RESUMO

The impact of iron chelation therapy (ICT) on overall survival (OS) and progression to acute myeloid leukemia (AML) in patients with iron overload and International Prognostic Scoring System low- or intermediate-risk myelodysplastic syndromes (MDS) is not well understood. We conducted a systematic review and meta-analysis of published studies of ICT in patients with MDS to better elucidate these relationships. We searched PubMed, EMBASE, Cochrane databases, and the World Health Organization Clinical Trial Registry for studies reporting the impact of ICT on OS in patients with low- or intermediate-risk MDS. Studies were examined for demographics, effect measures, and potential bias risk. Fixed and random-effects models were used to calculate adjusted OS and adjusted hazards ratio (aHR) estimates, respectively, among the different studies. Nine observational studies (four prospective and five retrospective) were identified. For patients with MDS, ICT was associated with an overall lower risk of mortality compared with no ICT (aHR 0.42; 95% confidence interval (CI) 0.28-0.62; P < 0.01); however, there was significant heterogeneity across the studies. In studies reporting progression to AML, ICT was not associated with decreased risk of progression (odds ratio 0.68; 95% CI 0.31-1.43; P < 0.030). This systematic review and meta-analysis of nine nonrandomized trials demonstrated significant reduction in risk of mortality in patients with iron overload and low- or intermediate-risk MDS treated with ICT; however, a causal relationship cannot be established. Randomized, controlled trials are needed to more definitively evaluate the relationship between ICT and survival in patients with iron overload and low- or intermediate-risk MDS.


Assuntos
Quelantes de Ferro/uso terapêutico , Modelos Biológicos , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/mortalidade , Ensaios Clínicos como Assunto , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Fatores de Risco , Taxa de Sobrevida
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