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1.
Photodiagnosis Photodyn Ther ; 45: 103961, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38163453

RESUMO

BACKGROUND: We present a case of bilateral maculopathy associated with deferoxamine mesylate (DFO) treatment. METHODS: A 53-year-old man with myelodysplastic syndrome (MDS) received DFO therapy due to elevated ferritin levels. He was then referred to ophthalmology clinic due to blurred vision. He was diagnosed as bilateral neurosensory retinal detachment of the macula. During follow up, best corrected visual acuity (BCVA), optical coherence tomography (OCT), fundus fluorescein angiography (FFA), and fundus autofluorescence (FAF) were evaluated. RESULTS: At first visit, OCT showed bilateral foveal neurosensory detachment. Hyperfluorescence of the macula and the peripapillary region were found on FFA. After discontinuation of DFO, BCVA improved from 20/120 to 20/60 with resolution of the foveal detachments on OCT scan. Four weeks later, FAF showed bilateral mottled hyperautofluorescence and hypoautofluorescence at the macula and the peripapillary region. CONCLUSION: Deferoxamine can cause acute retinal toxicity. Haematologists should be alert to visual complaints associated with DFO therapy, as early diagnosis and discontinuation of the medication allows recovery of visual function with residual fundus findings.


Assuntos
Degeneração Macular , Fotoquimioterapia , Doenças Retinianas , Masculino , Humanos , Pessoa de Meia-Idade , Desferroxamina/efeitos adversos , Tomografia de Coerência Óptica/métodos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes
2.
Transfus Apher Sci ; 62(3): 103702, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37055329

RESUMO

Drug-induced nephrolithiasis can arise from insoluble components within medications or crystallization of metabolites due to changes in metabolism and urinary pH. The connection between drugs utilized for iron chelation therapy (ICT) and nephrolithiasis is not well understood. In this report, we describe two pediatric patients diagnosed with nephrolithiasis while undergoing treatment with the chelating agents deferasirox, deferiprone, and deferoxamine for iron overload secondary to repeat blood transfusion.


Assuntos
Sobrecarga de Ferro , Nefrolitíase , Talassemia beta , Humanos , Criança , Terapia por Quelação/efeitos adversos , Quelantes de Ferro/efeitos adversos , Deferasirox/efeitos adversos , Deferiprona/uso terapêutico , Desferroxamina/efeitos adversos , Benzoatos/efeitos adversos , Triazóis , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Nefrolitíase/induzido quimicamente , Nefrolitíase/complicações , Nefrolitíase/tratamento farmacológico , Ferro/uso terapêutico , Talassemia beta/terapia
3.
Cochrane Database Syst Rev ; 3: CD012349, 2023 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-36877640

RESUMO

BACKGROUND: Regularly transfused people with sickle cell disease (SCD) and people with thalassaemia are at risk of iron overload. Iron overload can lead to iron toxicity in vulnerable organs such as the heart, liver and endocrine glands, which can be prevented and treated with iron-chelating agents. The intensive demands and uncomfortable side effects of therapy can have a negative impact on daily activities and wellbeing, which may affect adherence. OBJECTIVES: To identify and assess the effectiveness of different types of interventions (psychological and psychosocial, educational, medication interventions, or multi-component interventions) and interventions specific to different age groups, to improve adherence to iron chelation therapy compared to another listed intervention, or standard care in people with SCD or thalassaemia. SEARCH METHODS: We searched CENTRAL (Cochrane Library), MEDLINE, PubMed, Embase, CINAHL, PsycINFO, ProQuest Dissertations & Global Theses, Web of Science & Social Sciences Conference Proceedings Indexes and ongoing trial databases (13 December 2021). We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Haemoglobinopathies Trials Register (1 August 2022). SELECTION CRITERIA: For trials comparing medications or medication changes, only randomised controlled trials (RCTs) were eligible for inclusion. For studies including psychological and psychosocial interventions, educational interventions, or multi-component interventions, non-randomised studies of interventions (NRSIs), controlled before-after studies, and interrupted time series studies with adherence as a primary outcome were also eligible for inclusion. DATA COLLECTION AND ANALYSIS: For this update, two authors independently assessed trial eligibility and risk of bias, and extracted data. We assessed the certainty of the evidence using GRADE. MAIN RESULTS: We included 19 RCTs and one NRSI published between 1997 and 2021. One trial assessed medication management, one assessed an education intervention (NRSI) and 18 RCTs were of medication interventions. Medications assessed were subcutaneous deferoxamine, and two oral chelating agents, deferiprone and deferasirox. We rated the certainty of evidence as very low to low across all outcomes identified in this review. Four trials measured quality of life (QoL) with validated instruments, but provided no analysable data and reported no difference in QoL. We identified nine comparisons of interest. 1. Deferiprone versus deferoxamine We are uncertain whether or not deferiprone affects adherence to iron chelation therapy (four RCTs, unpooled, very low-certainty evidence), all-cause mortality (risk ratio (RR) 0.47, 95% confidence interval (CI) 0.18 to 1.21; 3 RCTs, 376 participants; very low-certainty evidence), or serious adverse events (SAEs) (RR 1.43, 95% CI 0.83 to 2.46; 1 RCT, 228 participants; very low-certainty evidence).  Adherence was reported as "good", "high" or "excellent" by all seven trials, though the data could not be analysed formally: adherence ranged from 69% to 95% (deferiprone, mean 86.6%), and 71% to 93% (deferoxamine, mean 78.8%), based on five trials (474 participants) only. 2. Deferasirox versus deferoxamine We are uncertain whether or not deferasirox affects adherence to iron chelation therapy (three RCTs, unpooled, very low-certainty evidence), although medication adherence was high in all trials. We are uncertain whether or not there is any difference between the drug therapies in serious adverse events (SAEs) (SCD or thalassaemia) or all-cause mortality (thalassaemia). 3. Deferiprone versus deferasirox We are uncertain if there is a difference between oral deferiprone and deferasirox based on a single trial in children (average age 9 to 10 years) with any hereditary haemoglobinopathy in adherence, SAEs and all-cause mortality. 4. Deferasirox film-coated tablet (FCT) versus deferasirox dispersible tablet (DT) One RCT compared deferasirox in different tablet forms. There may be a preference for FCTs, shown through a trend for greater adherence (RR 1.10, 95% CI 0.99 to 1.22; 1 RCT, 88 participants), although medication adherence was high in both groups (FCT 92.9%; DT 85.3%). We are uncertain if there is a benefit in chelation-related AEs with FCTs. We are uncertain if there is a difference in the incidence of SAEs, all-cause mortality or sustained adherence. 5. Deferiprone and deferoxamine combined versus deferiprone alone We are uncertain if there is a difference in adherence, though reporting was usually narrative as triallists report it was "excellent" in both groups (three RCTs, unpooled). We are uncertain if there is a difference in the incidence of SAEs and all-cause mortality.  6. Deferiprone and deferoxamine combined versus deferoxamine alone We are uncertain if there is a difference in adherence (four RCTs), SAEs (none reported in the trial period) and all-cause mortality (no deaths reported in the trial period). There was high adherence in all trials. 7. Deferiprone and deferoxamine combined versus deferiprone and deferasirox combined There may be a difference in favour of deferiprone and deferasirox (combined) in rates of adherence (RR 0.84, 95% CI 0.72 to 0.99) (one RCT), although it was high (> 80%) in both groups. We are uncertain if there is a difference in SAEs, and no deaths were reported in the trial, so we cannot draw conclusions based on these data (one RCT). 8. Medication management versus standard care We are uncertain if there is a difference in QoL (one RCT), and we could not assess adherence due to a lack of reporting in the control group. 9. Education versus standard care One quasi-experimental (NRSI) study could not be analysed due to the severe baseline confounding. AUTHORS' CONCLUSIONS: The medication comparisons included in this review had higher than average adherence rates not accounted for by differences in medication administration or side effects, though often follow-up was not good (high dropout over longer trials), with adherence based on a per protocol analysis. Participants may have been selected based on higher adherence to trial medications at baseline. Also, within the clinical trial context, there is increased attention and involvement of clinicians, thus high adherence rates may be an artefact of trial participation. Real-world, pragmatic trials in community and clinic settings are needed that examine both confirmed or unconfirmed adherence strategies that may increase adherence to iron chelation therapy. Due to lack of evidence this review cannot comment on intervention strategies for different age groups.


Assuntos
Anemia Falciforme , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Talassemia , Criança , Humanos , Anemia Falciforme/complicações , Anemia Falciforme/tratamento farmacológico , Quelantes , Terapia por Quelação , Desferroxamina/efeitos adversos , Ferro
4.
Front Biosci (Elite Ed) ; 14(3): 18, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-36137990

RESUMO

Beta thalassaemia major (TM), a potentially fatal haemoglobinopathy, has transformed from a fatal to a chronic disease in the last 30 years following the introduction of effective, personalised iron chelation protocols, in particular the use of oral deferiprone, which is most effective in the removal of excess iron from the heart. This transition in TM has been achieved by the accessibility to combination therapy with the other chelating drugs deferoxamine and deferasirox but also therapeutic advances in the treatment of related co-morbidities. The transition and design of effective personalised chelation protocols was facilitated by the development of new non-invasive diagnostic techniques for monitoring iron removal such as MRI T2*. Despite this progress, the transition in TM is mainly observed in developed countries, but not globally. Similarly, potential cures of TM with haemopoietic stem cell transplantation and gene therapy are available to selected TM patients but potentially carry high risk of toxicity. A global strategy is required for the transition efforts to become available for all TM patients worldwide. The same strategy could also benefit many other categories of transfusional iron loaded patients including other thalassaemias, sickle cell anaemia, myelodysplasia and leukaemia patients.


Assuntos
Quelantes de Ferro , Talassemia , Benzoatos/efeitos adversos , Deferasirox , Deferiprona/uso terapêutico , Desferroxamina/efeitos adversos , Humanos , Ferro , Quelantes de Ferro/efeitos adversos , Quelantes de Ferro/uso terapêutico , Piridonas/efeitos adversos , Medição de Risco , Talassemia/induzido quimicamente , Talassemia/tratamento farmacológico , Triazóis/efeitos adversos , Triazóis/uso terapêutico
5.
Blood Adv ; 6(4): 1243-1254, 2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-34847228

RESUMO

Many people with sickle cell disease (SCD) or other anemias require chronic blood transfusions, which often causes iron overload that requires chelation therapy. The iron chelator deferiprone is frequently used in individuals with thalassemia syndromes, but data in patients with SCD are limited. This open-label study assessed the efficacy and safety of deferiprone in patients with SCD or other anemias receiving chronic transfusion therapy. A total of 228 patients (mean age: 16.9 [range, 3-59] years; 46.9% female) were randomized to receive either oral deferiprone (n = 152) or subcutaneous deferoxamine (n = 76). The primary endpoint was change from baseline at 12 months in liver iron concentration (LIC), assessed by R2* magnetic resonance imaging (MRI). The least squares mean (standard error) change in LIC was -4.04 (0.48) mg/g dry weight for deferiprone vs -4.45 (0.57) mg/g dry weight for deferoxamine, with noninferiority of deferiprone to deferoxamine demonstrated by analysis of covariance (least squares mean difference 0.40 [0.56]; 96.01% confidence interval, -0.76 to 1.57). Noninferiority of deferiprone was also shown for both cardiac T2* MRI and serum ferritin. Rates of overall adverse events (AEs), treatment-related AEs, serious AEs, and AEs leading to withdrawal did not differ significantly between the groups. AEs related to deferiprone treatment included abdominal pain (17.1% of patients), vomiting (14.5%), pyrexia (9.2%), increased alanine transferase (9.2%) and aspartate transferase levels (9.2%), neutropenia (2.6%), and agranulocytosis (0.7%). The efficacy and safety profiles of deferiprone were acceptable and consistent with those seen in patients with transfusion-dependent thalassemia. This trial study was registered at www://clinicaltrials.gov as #NCT02041299.


Assuntos
Anemia Falciforme , Sobrecarga de Ferro , Talassemia , Adolescente , Anemia Falciforme/complicações , Anemia Falciforme/tratamento farmacológico , Transfusão de Sangue , Deferiprona/uso terapêutico , Desferroxamina/efeitos adversos , Feminino , Humanos , Quelantes de Ferro/efeitos adversos , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Masculino , Piridonas/efeitos adversos , Talassemia/complicações , Talassemia/tratamento farmacológico , Transferases
6.
Braz. J. Pharm. Sci. (Online) ; 58: e19409, 2022. graf
Artigo em Inglês | LILACS | ID: biblio-1383963

RESUMO

Abstract Naringin has been shown to exhibit satisfying iron chelation capacity. Considering the side effects of routinely-used iron chelator (desferrioxamine, DFO), we decided to evaluate the iron chelation potency of naringin to discover whether or not it can be a promising natural substitute for treatment of excessive iron-related diseases. 35 mice were classified into five groups of 7 and subjected to iron dextran administration to induce the iron-overload condition. Iron-overloaded mice were then treated with normal saline (as control), naringin or DFO Morphology changes, and iron deposition in liver tissues were studied using H&E and Perl's staining. The results revealed that naringin is more potent than DFO in removing excessive iron ions deposited in liver tissues, indicating that naringin is a promising natural compound for therapy of iron overload disorders


Assuntos
Animais , Masculino , Camundongos , Sobrecarga de Ferro/complicações , Flavanonas/análise , Organização e Administração , Desferroxamina/efeitos adversos
7.
BMC Ophthalmol ; 21(1): 277, 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34256738

RESUMO

BACKGROUND: Deferoxamine retinopathy is the informally designated term used to describe a characteristic pattern of outer retinal degeneration in iron-overloaded chronic anemia patients who are treated with deferoxamine. We hypothesize that insufficiently treated iron overloading and not only deferoxamine is the cause of the retinal degeneration. Our case report is based on exposure histories of two anemia patients and literature review. CASE PRESENTATION: Both anemia patients presented with bilateral visual loss secondary to photoreceptor and retinal pigment epithelium degeneration. Chart review showed that visual loss came after a year-long slow, and rather monotonous rise in plasma ferritin concentrations, with no obvious relation to iron chelator exposure. In one patient, the onset of symptomatic visual loss came after a bout of fever followed by two additional febrile episodes, all accompanied by plasma ferritin spikes. Adjustment of iron chelation therapy did not improve visual function. Experimental studies clearly show that both systemic and intraocular exposure to iron ions can induce retinal degeneration. CONCLUSION: The available evidence indicates that retinal degeneration in chronic anemia patients treated by deferoxamine is cause by insufficient iron chelation, not by deferoxamine. The actual role of iron chelating agents may be to promote a long enough survival to allow the slow development of retinal siderosis.


Assuntos
Sobrecarga de Ferro , Degeneração Retiniana , Talassemia beta , Desferroxamina/efeitos adversos , Humanos , Quelantes de Ferro/efeitos adversos , Sobrecarga de Ferro/induzido quimicamente , Sobrecarga de Ferro/complicações , Sobrecarga de Ferro/tratamento farmacológico , Degeneração Retiniana/induzido quimicamente , Epitélio Pigmentado da Retina
8.
Rev. bras. oftalmol ; 80(4): e0026, 2021. graf
Artigo em Inglês | LILACS | ID: biblio-1288636

RESUMO

ABSTRACT A 10-year-old Malay girl with underlying HbE/beta-thalassemia, on regular blood transfusion and deferoxamine iron chelation therapy, presented with two-month history of bilateral blurring of vision. On examination, her vision was 6/36 both eyes. Other optic nerve functions were normal. Anterior segment examination of both eyes was unremarkable. Fundus examination of both eyes revealed dull foveal reflex. Optical coherence tomography of both maculae showed increased central subfield thickness. Fundus fluorescence angiography showed patchy hypofluorescence over macular region for both eyes and late staining, indicating retinal pigment epithelium anomalies. A diagnosis of iron-chelation-therapy-related bilateral maculopathy was made. Patient was co-managed with pediatric hematology team to adjust the dose of deferoxamine, and was given three monthly appointments to monitor the progression of maculopathy at the ophthalmology clinic. However patient defaulted ophthalmology follow-up after the first visit.


RESUMO Uma menina malaia de 10 anos de idade com doença de base- B/beta-talassemia, em transfusão de sangue regular e terapia quelante de ferro deferoxamina, apresentou história de dois meses de visão turva bilateral. Ao exame, sua visão era de 6/36 em ambos os olhos. Outras funções do nervo óptico estavam normais. O exame do segmento anterior de ambos os olhos foi normal. Exame do fundo de ambos os olhos revelou reflexo foveal opaco. A tomografia de coerência óptica de ambas as máculas mostrou aumento da espessura do subcampo central. A angiografia de fluorescência do fundo mostrou hipofluorescência irregular sobre a região macular de ambos os olhos e coloração tardia, indicando anomalias de epitélio pigmentar da retina. Um diagnóstico de maculopatia bilateral relacionada à terapia quelante de ferro foi feito. A paciente foi avaliada em conjunto com a equipe de hematologia pediátrica para ajustar a dose de deferoxamina, e foram oferecidas três consultas mensais na clínica oftalmológica, para monitorar a progressão da maculopatia. No entanto, ela não compareceu para acompanhamento oftalmológico após a primeira visita.


Assuntos
Humanos , Feminino , Criança , Sideróforos/efeitos adversos , Talassemia beta/tratamento farmacológico , Desferroxamina/efeitos adversos , Reação Transfusional , Degeneração Macular/complicações , Transfusão de Sangue , Sideróforos/uso terapêutico , Talassemia beta/diagnóstico , Desferroxamina/uso terapêutico
9.
Cochrane Database Syst Rev ; 11: CD009280, 2020 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-33236783

RESUMO

BACKGROUND: Stroke is the second leading cause of death and a major cause of morbidity worldwide. Retrospective clinical and animal studies have demonstrated neuroprotective effects of iron chelators in people with haemorrhagic or ischaemic stroke. This is the first update of the original Cochrane Review published in 2012. OBJECTIVES: To evaluate the effectiveness and safety of iron-chelating drugs in people with acute stroke. SEARCH METHODS: We searched the Cochrane Stroke Group Trials Register (2 September 2019), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2019, Issue 9; 2 September 2019), MEDLINE Ovid (2 September 2019), Embase Ovid (2 September 2019), and Science Citation Index (2 September 2019). We also searched ongoing trials registers. SELECTION CRITERIA: We included randomised controlled trials (RCTs) of iron chelators versus no iron chelators or placebo for the treatment of acute stroke, including subarachnoid haemorrhage. DATA COLLECTION AND ANALYSIS: Two review authors independently screened the search results. We obtained the full texts of potentially relevant studies and evaluated them for eligibility. We assessed risk of bias using the Cochrane 'Risk of bias' tool, and the certainty of evidence using the GRADE approach. MAIN RESULTS: Two RCTs (333 participants) were eligible for inclusion; both compared the iron-chelating agent deferoxamine against placebo. Both studies evaluated participants with spontaneous intracerebral haemorrhage. We assessed one study to have a low risk of bias; the other study had potential sources of bias. The limited and heterogeneous data did not allow for meta-analysis of the outcome parameters. The evidence suggests that administration of deferoxamine may result in little to no difference in deaths (8% in placebo vs 8% in deferoxamine at 180 days; 1 RCT, 291 participants; low-certainty evidence). These RCTs suggest that there may be little to no difference in good functional outcome (modified Rankin Scale score 0 to 2) between groups at 30, 90 and 180 days (placebo vs deferoxamine: 67% vs 57% at 30 days and 36% vs 45% at 180 days; 2 RCTs, 333 participants; low-certainty evidence). One RCT suggests that administration of deferoxamine may not increase the number of serious adverse events or deaths (placebo vs deferoxamine: 33% vs 27% at 180 days; risk ratio 0.81, 95 % confidence interval 0.57 to 1.16; 1 RCT, 291 participants; low-certainty evidence). No data were available on any deaths within the treatment period. Deferoxamine may result in little to no difference in the evolution of National Institute of Health Stroke Scale scores from baseline to 90 days (placebo vs deferoxamine: 13 to 4 vs 13 to 3; P = 0.37; 2 RCTs, 333 participants; low-certainty evidence). Deferoxamine may slightly reduce relative oedema surrounding intracerebral haemorrhage at 15 days (placebo vs deferoxamine: 1.91 vs 10.26; P = 0.042; 2 RCTs, 333 participants; low-certainty evidence). Neither study reported quality of life. AUTHORS' CONCLUSIONS: We identified two eligible RCTs for assessment. We could not demonstrate any benefit for the use of iron chelators in spontaneous intracerebral haemorrhage. The added value of iron-chelating therapy in people with ischaemic stroke or subarachnoid haemorrhage remains unknown.


Assuntos
Desferroxamina/uso terapêutico , Acidente Vascular Cerebral Hemorrágico/tratamento farmacológico , Quelantes de Ferro/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Doença Aguda , Viés , Desferroxamina/efeitos adversos , Acidente Vascular Cerebral Hemorrágico/mortalidade , Humanos , Quelantes de Ferro/efeitos adversos , Fármacos Neuroprotetores/efeitos adversos , Placebos/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
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
11.
Ear Nose Throat J ; 98(8): NP125-NP130, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31142160

RESUMO

Ocular and ophthalmological adverse effects may be seen in ß-thalassemia major (BTM) patients treated with regular blood transfusions and iron-chelating agents. We hypothesized that olfactory dysfunction may be present in this population. In this study, we aimed to investigate olfactory dysfunction in patients with BTM and determine the etiological factors. A total of 43 patients with BTM were included in the study. Forty-three patients without any nasal complaints, history of facial trauma, or nasal surgery were included as the controls. All participants had nasal endoscopy. The iron-chelating agents used, their duration of use, as well as hemoglobin and ferritin levels of the BTM patients were recorded. Sniffin' Sticks test (SST) was used to assess olfactory functions, and BTM and control groups were compared for the results. The correlations of SST scores with the other study parameters were analyzed. Eight (18.6%) of 43 patients in the BTM group had hyposmia while none of the patients in the control group had hyposmia (P < .001). Older age, low-hemoglobin level, and longer use of deferoxamine were found to be correlated with olfactory dysfunction. Olfactory dysfunction may be seen in BTM patients treated with iron-chelating agents. The results of this study suggest that screening for olfactory function may be needed in routine follow-up of BTM patients.


Assuntos
Desferroxamina/uso terapêutico , Quelantes de Ferro/uso terapêutico , Transtornos do Olfato/etiologia , Talassemia beta/sangue , Talassemia beta/tratamento farmacológico , Adolescente , Adulto , Fatores Etários , Desferroxamina/efeitos adversos , Feminino , Ferritinas/sangue , Hemoglobinas/metabolismo , Humanos , Quelantes de Ferro/efeitos adversos , Masculino , Adulto Jovem , Talassemia beta/complicações
12.
Ann Nucl Med ; 33(2): 119-127, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30406361

RESUMO

OBJECTIVE: We conducted the present phase I/IIa positron emission tomography (PET) imaging study with 89Zr conjugated with desferroxamine-IAB2M (89Zr-Df-IAB2M), an anti-prostate-specific membrane-antigen minibody, to assess its safety and feasibility in patients with urological cancer. METHODS: 89Zr-Df-IAB2M was synthetized by IBA Molecular (Somerset, NJ, USA) and transported by air to Tsukuba Molecular Imaging Center (Tsukuba, Ibaraki, Japan).17 patients received 74 MBq (2 mCi) of 89Zr-Df-IAB2M at total mass doses of 10 mg. Whole-body and plasma clearance, normal-organ and lesion uptake, and radiation absorbed dose were estimated. We also preliminarily tested the performance of 89Zr-immuno-PET imaging for 13 patients with prostate cancer and 4 patients with other urological cancer. RESULTS: The administration of 89Zr-Df-IAB2M was well-tolerated, and no infusion-related reactions were observed in any patient. No adverse events were noted in the laboratory parameters, vital signs, or other parameters. The plasma clearance was biphasic, with an initial rapid phase (t 1/2 fast: 10.1 ± 3.4 h) followed by a slow phase (t 1/2 slow: 49.0 ± 22.7 h). The half-life of radioactivity in the whole body (WB t1/2) was 237 ± 9 h. The highest absorbed radiation dose was 1.67 mGy/MBq, observed in the liver and kidney. The effective dose was 0.68 ± 0.08 mSv/MBq. The radiation dose rate at 0.5 m distance from the patient was 8.67 µSv/h on day 1, and decreased to 2.26 µSv/h at 5 days after injection. Both bone and lymph node metastases were detected with 89Zr-Df-IAB2M by 24 or 48 h imaging. CONCLUSIONS: Administration of 89Zr-Df-IAB2M was well-tolerated and safe in terms of adverse events and radiation exposure and protection. 89Zr-Df-IAB2M is feasible for usage by long-distance transportation. Further studies are warranted for analysis of its use for tumor lesion detection (UMIN000015356).


Assuntos
Desferroxamina , Tomografia por Emissão de Pósitrons , Radioisótopos , Neoplasias Urológicas/diagnóstico por imagem , Zircônio , Idoso , Desferroxamina/efeitos adversos , Estudos de Viabilidade , Feminino , Humanos , Marcação por Isótopo , Masculino , Pessoa de Meia-Idade , Segurança
13.
Expert Rev Clin Pharmacol ; 11(6): 641-650, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29727586

RESUMO

BACKGROUND: To compare the efficacy and safety of desferrioxamine (DFO), deferiprone (DFP), deferasirox (DFX) and silymarin in patients with either thalassemia or sickle cell disorder through network meta-analysis. METHODS: Electronic databases were searched for appropriate randomized clinical trials comparing iron chelators in patients with iron overload. Random effects model was used to generate direct, indirect and mixed treatment comparison pooled estimates for the following outcomes: serum ferritin, liver iron concentration (LIC), changes in serum ferritin, mortality, urine iron excretion, adverse events, neutropenia, agranulocytosis and number of patients withdrawing the chelating therapy. RESULTS: Thirty-two clinical trials were included in the meta-analysis. DFX/DFO was associated with better serum ferritin levels compared to DFO, DFX, DFO/Silymarin and DFP/DFO. DFX/DFO also lower LIC significantly compared to DFO. DFP/DFO was associated with higher LVEF, low risk of adverse events and reduced end of serum ferritin compared to DFO. Combination of silymarin with either DFP or DFX was observed with reduced end of treatment serum ferritin compared to using either of the drugs alone. DFP was observed with better effects in sickle cell disease. The strength of evidence was very low for most of the comparisons. CONCLUSION: Relative estimates between the individual iron chelators have been established. However, this evidence should be considered preliminary and may change with the results of future head-to-head clinical trials.


Assuntos
Anemia Falciforme/tratamento farmacológico , Quelantes de Ferro/uso terapêutico , Talassemia/tratamento farmacológico , Benzoatos/administração & dosagem , Benzoatos/efeitos adversos , Benzoatos/uso terapêutico , Deferasirox , Deferiprona , Desferroxamina/administração & dosagem , Desferroxamina/efeitos adversos , Desferroxamina/uso terapêutico , Quimioterapia Combinada , Humanos , Quelantes de Ferro/administração & dosagem , Quelantes de Ferro/efeitos adversos , Sobrecarga de Ferro , Metanálise em Rede , Piridonas/administração & dosagem , Piridonas/efeitos adversos , Piridonas/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Silimarina/administração & dosagem , Silimarina/efeitos adversos , Silimarina/uso terapêutico , Triazóis/administração & dosagem , Triazóis/efeitos adversos , Triazóis/uso terapêutico
14.
Am J Hematol ; 93(7): 943-952, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29635754

RESUMO

Red blood cell transfusions have become standard of care for the prevention of life-threatening anemia in patients with ß-thalassemia and sickle cell disease (SCD). However, frequent transfusions can lead to accumulation of iron that can result in liver cirrhosis, diabetes mellitus, arthritis, arrhythmias, cardiomyopathy, heart failure, and hypogonadotropic hypogonadism. Iron chelation therapy has been shown to reduce serum ferritin levels and liver iron content, but limitations of trial design have prevented any demonstration of improved survival. The objective of this systematic review was to investigate the impact of iron chelation therapy on overall and event-free survival in patients with ß-thalassemia and SCD. Eighteen articles discussing survival in ß-thalassemia and 3 in SCD were identified. Overall iron chelation therapy resulted in better overall survival, especially if it is instituted early and compliance is maintained. Comparative studies did not show any significant differences between available iron chelation agents, although there is evidence that deferiprone is better tolerated than deferoxamine and that compliance is more readily maintained with the newer oral drugs, deferiprone and deferasirox. Iron chelation therapy, particularly the second-generation oral agents, appears to be associated with improved overall and event-free survival in transfusion-dependent patients with ß-thalassemia and patients with SCD.


Assuntos
Anemia Falciforme/tratamento farmacológico , Quelantes de Ferro/uso terapêutico , Talassemia beta/tratamento farmacológico , Anemia Falciforme/complicações , Anemia Falciforme/mortalidade , Transfusão de Sangue , Deferiprona/efeitos adversos , Deferiprona/uso terapêutico , Desferroxamina/efeitos adversos , Desferroxamina/uso terapêutico , Humanos , Quelantes de Ferro/efeitos adversos , Adesão à Medicação , Análise de Sobrevida , Talassemia beta/mortalidade
15.
Ear Nose Throat J ; 96(10-11): E8-E12, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29121379

RESUMO

Ocular and ophthalmologic adverse effects may occur in patients with ß-thalassemia major (BTM) treated regularly with blood transfusions and iron-chelating agents. We hypothesized that olfactory dysfunction may be present in this patient population. We aimed to investigate olfactory dysfunction in patients with BTM and to determine etiologic factors. A total of 43 patients with BTM were included in the study. Forty-three subjects without nasal complaints, history of facial trauma, or nasal surgery were included as the controls. All participants had nasal endoscopy. The use of iron-chelating agents by patients with BTM and their duration of use were recorded, as well as hemoglobin and ferritin levels. The Sniffin' Sticks test (SST) was used to assess olfactory function, comparing results between the BTM and control groups. The correlations of SST scores with the other study parameters were analyzed. Eight (18.6%) of 43 patients in the BTM group and none of the subjects in the control group had hyposmia (p < 0.001). Older age, low hemoglobin level, and longer use of deferoxamine were found to be correlated with olfactory dysfunction. Olfactory dysfunction can occur in patients with BTM treated with iron-chelating agents. The results suggest that screening for olfactory function should be part of the routine follow-up of patients with BTM.


Assuntos
Quelantes de Ferro/efeitos adversos , Transtornos do Olfato/induzido quimicamente , Talassemia beta/tratamento farmacológico , Adolescente , Adulto , Benzoatos/administração & dosagem , Benzoatos/efeitos adversos , Deferasirox , Deferiprona , Desferroxamina/administração & dosagem , Desferroxamina/efeitos adversos , Feminino , Humanos , Quelantes de Ferro/administração & dosagem , Masculino , Pessoa de Meia-Idade , Piridonas/administração & dosagem , Piridonas/efeitos adversos , Fatores de Risco , Triazóis/administração & dosagem , Triazóis/efeitos adversos , Adulto Jovem , Talassemia beta/fisiopatologia
16.
Int J Hematol ; 103(5): 537-44, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26861970

RESUMO

The life expectancy of thalassemic patients has increased, and now approaches that of healthy individuals, thanks to improved treatment regimens. However, pregnancy in women with ß-Thalassemia Μajor remains a challenging condition. Recent advances in managing this haemoglobinopathy offer the potential for safe pregnancies with favorable outcome. However, clinical data regarding the use of chelation therapy during pregnancy are limited, and it is unclear whether these agents impose any risk to the developing fetus. Successful pregnancies following unintentional treatment with deferoxamine or deferasirox have rarely been reported. Generally, chelators are not recommended during pregnancy. Regarding the new oral chelators, data on fetotoxicity are lacking. In the present study, we describe the evolution and successful outcome of nine pregnancies in six Greek thalassemic women who received deferasirox inadvertently during early pregnancy, and review the literature regarding fetal anomalies due to chelators. Use of chelation before embarking upon a non-programmed pregnancy remains a difficult and unresolved question. In our study, chelation treatment during pregnancy did not prevent the delivery of healthy children. Nonetheless, the use of deferasirox is contraindicated in pregnant women, based on the product label. Deferasirox should only be used during pregnancy if the potential benefit outweighs the potential fetal risk.


Assuntos
Benzoatos/uso terapêutico , Desferroxamina/uso terapêutico , Quelantes de Ferro/uso terapêutico , Complicações Hematológicas na Gravidez/tratamento farmacológico , Piridonas/uso terapêutico , Triazóis/uso terapêutico , Talassemia beta/complicações , Talassemia beta/tratamento farmacológico , Adulto , Benzoatos/efeitos adversos , Terapia por Quelação , Deferasirox , Deferiprona , Desferroxamina/efeitos adversos , Feminino , Feto/efeitos dos fármacos , Humanos , Recém-Nascido , Quelantes de Ferro/efeitos adversos , Gravidez , Resultado da Gravidez , Piridonas/efeitos adversos , Triazóis/efeitos adversos
17.
Drug Des Devel Ther ; 10: 465-81, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26893541

RESUMO

The prevalence rate of thalassemia, which is endemic in Southeast Asia, the Middle East, and the Mediterranean, exceeds 100,000 live births per year. There are many genetic variants in thalassemia with different pathological severity, ranging from a mild and asymptomatic anemia to life-threatening clinical effects, requiring lifelong treatment, such as regular transfusions in thalassemia major (TM). Some of the thalassemias are non-transfusion-dependent, including many thalassemia intermedia (TI) variants, where iron overload is caused by chronic increase in iron absorption due to ineffective erythropoiesis. Many TI patients receive occasional transfusions. The rate of iron overloading in TI is much slower in comparison to TM patients. Iron toxicity in TI is usually manifested by the age of 30-40 years, and in TM by the age of 10 years. Subcutaneous deferoxamine (DFO), oral deferiprone (L1), and DFO-L1 combinations have been effectively used for more than 20 years for the treatment of iron overload in TM and TI patients, causing a significant reduction in morbidity and mortality. Selected protocols using DFO, L1, and their combination can be designed for personalized chelation therapy in TI, which can effectively and safely remove all the excess toxic iron and prevent cardiac, liver, and other organ damage. Both L1 and DF could also prevent iron absorption. The new oral chelator deferasirox (DFX) increases iron excretion and decreases liver iron in TM and TI. There are drawbacks in the use of DFX in TI, such as limitations related to dose, toxicity, and cost, iron load of the patients, and ineffective removal of excess iron from the heart. Furthermore, DFX appears to increase iron and other toxic metal absorption. Future treatments of TI and related iron-loading conditions could involve the use of the iron-chelating drugs and other drug combinations not only for increasing iron excretion but also for preventing iron absorption.


Assuntos
Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Talassemia/tratamento farmacológico , Benzoatos/efeitos adversos , Benzoatos/uso terapêutico , Terapia por Quelação/métodos , Deferasirox , Deferiprona , Desferroxamina/efeitos adversos , Desferroxamina/uso terapêutico , Humanos , Quelantes de Ferro/efeitos adversos , Sobrecarga de Ferro/etiologia , Piridonas/efeitos adversos , Piridonas/uso terapêutico , Síndrome , Talassemia/complicações , Triazóis/efeitos adversos , Triazóis/uso terapêutico
18.
Ear Nose Throat J ; 94(12): 481-5, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26670754

RESUMO

The predictive value of pure-tone audiometry (PTA) in the early detection of ototoxicity has been questioned, particularly in the higher frequencies. Otoacoustic emissions testing appears to be more sensitive to cochlear insult than conventional PTA. We conducted a cross-sectional descriptive study to compare the efficacy of distortion-product otoacoustic emissions (DPOAE) testing with that of PTA as a method of audiologic monitoring. Our study group was made up of 159 patients (318 ears)-69 males (43.4%) and 90 females (56.6%), aged 5 to 61 years (mean: 23.59 ± 12.55). All patients had been diagnosed with either ß-thalassemia major (BTM) or ß-thalassemia intermedia (BTI), and all had received at least 1 year of treatment within the previous year with an iron chelator-either deferasirox, desferrioxamine (deferoxamine in the United States), deferiprone, or a combination of desferrioxamine and deferiprone. PTA and DPOAE evaluations were performed by the same audiologist using the same audiometer for all patients. In the right ears, the overall incidence of ototoxicity as manifested by sensorineural hearing loss was 39.0% on PTA and 22.0% on DPOAE testing; in the left ears, the corresponding figures were 27.7 and 19.5%, respectively. There were no statistically significant differences in the incidence of ototoxicity between the BTM and BTI groups with any of the four different drug regimens on PTA (p = 0.765, p = 0.378, p = 0.265, and p = 0.579, respectively) or on DPOAE testing (p = 0.890, p = 0.263, p = 0.390, and p = 0.340, respectively). Based on these data, we found no significant difference between PTA and DPOAE testing in their ability to detect ototoxicity. We conclude that periodic testing with both PTA and DPOAE is necessary for patients with suspected ß-thalassemia in order arrive at a prompt diagnosis and initiate timely management.


Assuntos
Perda Auditiva Neurossensorial/induzido quimicamente , Quelantes de Ferro/efeitos adversos , Talassemia beta/tratamento farmacológico , Adolescente , Adulto , Audiometria de Tons Puros , Benzoatos/efeitos adversos , Benzoatos/uso terapêutico , Criança , Pré-Escolar , Estudos Transversais , Deferasirox , Deferiprona , Desferroxamina/efeitos adversos , Desferroxamina/uso terapêutico , Feminino , Perda Auditiva Neurossensorial/diagnóstico , Humanos , Quelantes de Ferro/uso terapêutico , Masculino , Pessoa de Meia-Idade , Piridonas/efeitos adversos , Piridonas/uso terapêutico , Triazóis/efeitos adversos , Triazóis/uso terapêutico , Adulto Jovem
19.
Blood ; 125(25): 3868-77, 2015 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-25934475

RESUMO

Deferasirox (DFX) monotherapy is effective for reducing myocardial and liver iron concentrations (LIC), although some patients may require intensive chelation for a limited duration. HYPERION, an open-label single-arm prospective phase 2 study, evaluated combination DFX-deferoxamine (DFO) in patients with severe transfusional myocardial siderosis (myocardial [m] T2* 5-<10 ms; left ventricular ejection fraction [LVEF] ≥56%) followed by optional switch to DFX monotherapy when achieving mT2* >10 ms. Mean dose was 30.5 mg/kg per day DFX and 36.3 mg/kg per day DFO on a 5-day regimen. Geometric mean mT2* ratios (Gmeanmonth12/24/Gmeanbaseline) were 1.09 and 1.30, respectively, increasing from 7.2 ms at baseline (n = 60) to 7.7 ms at 12 (n = 52) and 9.5 ms at 24 months (n = 36). Patients (17 of 60; 28.3%) achieved mT2* ≥10 ms and ≥10% increase from baseline at month 24; 15 switched to monotherapy during the study based on favorable mT2*. LIC decreased substantially from a baseline of 33.4 to 12.8 mg Fe/g dry weight at month 24 (-52%). LVEF remained stable with no new arrhythmias/cardiac failure. Five patients discontinued with mT2* <5 ms and 1 died (suspected central nervous system infection). Safety was consistent with established monotherapies. Results show clinically meaningful improvements in mT2* in about one-third of patients remaining on treatment at month 24, alongside rapid decreases in LIC in this heavily iron-overloaded, difficult-to-treat population. Combination therapy may be useful when rapid LIC reduction is required, regardless of myocardial iron overload. This trial was registered at www.clinicaltrials.gov as #NCT01254227.


Assuntos
Benzoatos/administração & dosagem , Desferroxamina/administração & dosagem , Quelantes de Ferro/administração & dosagem , Sobrecarga de Ferro/tratamento farmacológico , Sideróforos/administração & dosagem , Triazóis/administração & dosagem , Adolescente , Adulto , Benzoatos/efeitos adversos , Criança , Deferasirox , Desferroxamina/efeitos adversos , Feminino , Coração/efeitos dos fármacos , Humanos , Quelantes de Ferro/efeitos adversos , Sobrecarga de Ferro/etiologia , Fígado/química , Fígado/efeitos dos fármacos , Masculino , Miocárdio/química , Sideróforos/efeitos adversos , Reação Transfusional , Triazóis/efeitos adversos , Adulto Jovem
20.
Malays J Pathol ; 37(1): 35-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25890611

RESUMO

UNLABELLED: ß-thalassemia is the most common genetic disorder worldwide with an increased prevalence around the Mediterranean, Indian subcontinent and in South-East Asia. Various siderotic and non-siderotic complications significantly impact the quality of life. Thalassemic patients are also at risk of zinc deficiency due to diverse causes including desferrioxamine chelation. This study sought to investigate the prevalence of zinc deficiency in beta thalassemia major patients on desferrioxamine for iron chelation. STUDY DESIGN: This was a descriptive, prospective, cross-sectional study over a 6-month period. 63 cases of beta thalassemia major within the age group of 5-15 years on desferrioxamine for at least 1 year, were included. Basic patient demographics such as age, gender and duration of disease were recorded. Serum zinc levels were determined by atomic absorption spectrophotometry. RESULTS: The mean age of patients was 10.84±3.47 (5 to 15) years. There were 35 (55.6%) males and 28(44.4%) females. The prevalence of zinc deficiency (zinc levels>50 µg/dl) was 22.2%. Proportions of deficiency were higher in males with a duration of disease beyond 10 years. CONCLUSIONS: Zinc deficiency is not uncommon in beta thalassemia patients on desferrioxamine. We suggest that zinc levels be regularly monitored in these patients.


Assuntos
Desferroxamina/efeitos adversos , Deficiências Nutricionais/induzido quimicamente , Quelantes de Ferro/efeitos adversos , Zinco/deficiência , Talassemia beta/tratamento farmacológico , Adolescente , Biomarcadores/sangue , Criança , Pré-Escolar , Estudos Transversais , Deficiências Nutricionais/sangue , Deficiências Nutricionais/diagnóstico , Deficiências Nutricionais/epidemiologia , Feminino , Humanos , Masculino , Paquistão/epidemiologia , Prevalência , Estudos Prospectivos , Espectrofotometria Atômica , Fatores de Tempo , Resultado do Tratamento , Zinco/sangue , Talassemia beta/sangue , Talassemia beta/diagnóstico , Talassemia beta/epidemiologia
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