Abstract Introduction Magnetic resonance imaging (MRI) T2* technique is used to assess iron overload in the heart, liver and pancreas of thalassaemic patients. Optimal iron chelation and expected tissue iron response rates remain under investigation. The objective of this study was to analyse serum ferritin and the iron concentration in the heart, liver and pancreas measured by MRI T2*/R2* during regular chelation therapy in a real-world cohort of patients with thalassemia. Methods We evaluated thalassaemic patients ≥ 7 years old undergoing chelation/transfusion therapy by MRI and assessed serum ferritin at baseline and follow-up from 2004-2011. Results We evaluated 136 patients, 92% major thalassaemic, with a median age of 18 years, and median baseline ferritin 2.033ng/ml (range: 59-14,123). Iron overload distribution was: liver (99%), pancreas (74%) and heart (36%). After a median of 1.2 years of follow-up, the iron overload in the myocardium reduced from 2,63 Fe mg/g to 2,05 (p 0.003). The optimal R2* pancreas cut-off was 148 Hertz, achieving 78% sensitivity and 73% specificity. However, when combining the R2* pancreas cut off ≤ 50 Hertz and a ferritin ≤ 1222 ng/ml, we could reach a negative predictive value (NPV) of 98% for cardiac siderosis. Only 28% were undergoing combined chelation at baseline assessment, which increased up to 50% on follow up evaluation. Conclusions Chelation therapy significantly reduced cardiac siderosis in thalassaemic patients. In patients with moderate/severe liver iron concentration undergoing chelation therapy, ferritin levels and myocardium iron improved earlier than the liver siderosis.

FUNDAMENTO: Pacientes com talassemia major (TM) apresentam hemólise crônica e necessitam de transfusões sanguíneas egularmente que podem causar cardiomiopatia por sobrecarga de ferro e insuficiência cardíaca crônica. A hemocromatose é caracterizada por acúmulo excessivo de ferro nos tecidos; acometimento do coração é a principal causa de óbito em pacientes com talassemia. OBJETIVO: Avaliar as estruturas e a função cardíaca por meio de ecocardiografia com Doppler convencional e Doppler tecidual em pacientes com TM, sem evidência clínica de insuficiência cardíaca. MÉTODOS: Trata-se de estudo observacional prospectivo de 18 pacientes com TM que recebem transfusão sanguínea regularmente. Para avaliar, separadamente, os efeitos da anemia e da transfusão sanguínea, dois grupos controles pareados por gênero, idade, peso e altura foram incluídos: um com indivíduos saudáveis (Saudável, n = 18) e outro com pacientes com anemia por deficiência de ferro (Anemia, n = 18). Análise estatística foi realizada utilizando ANOVA seguida pelo teste de Tukey ou Kruskal-Wallis e teste de Dunn. RESULTADOS: As seguintes variáveis ecocardiográficas apresentaram valores significativamente mais elevados no grupo TM do que nos grupos Anemia e Saudável: índice de volume do átrio esquerdo (Saudável: 16,4 ± 6,08; Anemia: 17,9 ± 7,02; TM: 24,1 ± 8,30 cm/m); razão E/Em septal mitral (Saudável: 6,55 ± 1,60; Anemia: 6,74 ± 0,74; TM: 8,10 ± 1,31) e duração do fluxo reverso em veias pulmonares [Saudável: 74,0 (59,0-74,0); Anemia: 70,5 (67,0-74,0); TM: 111 (87,0-120) ms]. Arazão E/A mitral foi maior no grupo TM do que no grupo Anemia (Saudável: 1,80 ± 0,40; Anemia: 1,80 ± 0,24; TM: 2,03 ± 0,34). Não foram encontradas diferenças entre os grupos em variáveis estruturais do ventrículo esquerdo e em índices de função sistólica. CONCLUSÃO: A ecocardiografia com Doppler convencional e o Doppler tecidual permite que alterações na função diastólica do ventrículo esquerdo sejam identificadas em pacientes assintomáticos com talassemia major.

BACKGROUND: Patients with thalassemia major present chronic hemolysis and require regular blood transfusions which may cause iron overload cardiomyopathy and chronic heart failure. Hemochromatosis is characterized by excessive iron accumulation in tissues, and heart involvement is the main cause of death in patients with thalassemia. OBJECTIVE: The aim of this study was to evaluate cardiac structure and function by conventional Doppler echocardiography and tissue Doppler imaging in patients with TM and no clinical evidence of heart failure. METHODS: This is a prospective observational study including 18 patients with thalassemia major (TM) receiving regular blood transfusion. To separately evaluate anemia and blood transfusion effects, two gender, age, weight, and height-matched control groups were included: one with healthy individuals (Healthy, n=18) and one with iron deficient anemia patients (Anemia, n=18). Statistical analysis was performed using ANOVA followed by Tukey's test or Kruskal-Wallis's and Dunn's test. RESULTS: The following echocardiographic variables presented significantly higher values in TM than the Anemia and Healthy groups: left atrium volume index (Healthy: 16.4±6.08; Anemia: 17.9±7.02; TM: 24.1±8.30 cm³/m²); mitral septal E/Em ratio (Healthy: 6.55±1.60; Anemia: 6.74±0.74; TM: 8.10±1.31); and duration of reverse pulmonary vein flow [Healthy: 74.0 (59.0-74.0); Anemia: 70.5 (67.0-74.0); TM: 111 (87.0-120) ms]. The mitral E/A ratio was higher in TM than Anemia (Healthy: 1.80±0.40; Anemia: 1.80±0.24; TM: 2.03±0.34). No differences were found in left ventricular structures and systolic function indexes. CONCLUSION: Conventional Doppler echocardiography and tissue Doppler allow changes in left ventricular diastolic function to be identified in asymptomatic patients with thalassemia major.

In the absence of an iron chelating agent, patients with beta-thalassemia on regular transfusions present complications of transfusion-related iron overload. Without iron chelation therapy, heart disease is the major cause of death; however, hepatic and endocrine complications also occur. Currently there are three iron chelating agents available for continuous use in patients with thalassemia on regular transfusions (desferrioxamine, deferiprone, and deferasirox) providing good results in reducing cardiac, hepatic and endocrine toxicity. These practice guidelines, prepared by the Scientific Committee of Associação Brasileira de Thalassemia (ABRASTA), presents a review of the literature regarding iron overload assessment (by imaging and laboratory exams) and the role of T2* magnetic resonance imaging (MRI) to control iron overload and iron chelation therapy, with evidence-based recommendations for each clinical situation. Based on this review, the authors propose an iron chelation protocol for patients with thalassemia under regular transfusions.

Objetivo: Avaliar o acúmulo de ferro em diferentes órgãos por meio da ressonância nuclear magnética T2* e correlacionar os resultados aos níveis de ferritina sérica, ferro plasmático lábil e outros órgãos envolvidos. Métodos: Foram avaliados retrospectivamente 115 pacientes talassêmicos (sendo 65 mulheres). A concentração hepática de ferro foi determinada em biópsia de 11 pacientes; os resultados foram comparados com os valores de T2* fígado. Resultados: a ferritina sérica média foi de 2.676,5 +/- 2.051,7 ng/mL. O ferro plasmático lábil foi anormal (> 0,6 Unidades/mL) em 48/83 pacientes (57%). A média dos valores de T2* no fígado foi 3,91 ± 3,95 ms, sugerindo siderose hepática em 92,1% pacientes. A média do T2* cardíaco foi de 24,96 ± 14,17 ms e 36% dos pacientes apresentavam siderose cardíaca (T2* < 20ms), dos quais 19% (22/115) já apresentavam sobrecarga cardíaca grave (T2* < 10 ms). A média de T2* no pâncreas foi de 11,12 ± 11,20 ms, perfazendo um total de 83,5% de pacientes com sobrecarga de ferro pancreático (T2* < 21 ms). Houve correlação significativa, curvilínea e inversa entre T2* fígado e a concentração de ferro hepática (r = −0,878; p <0,001) e correlação moderada entre T2* pâncreas e T2* miocárdio (r = 0,546; p <0,0001). Conclusão: Uma elevada taxa de acometimento hepático, pancreático e cardíaco por sobrecarga férrica foi demonstrada. Os níveis de ferritina não puderam prever sobrecarga de ferro hepático, cardíaco ou pancreáticos medidos por meio da ressonância nuclear magnética T2*. Não houve correlação entre a sobrecarga de ferro no fígado, pâncreas e miocárdio, nem entre a ferritina e os níveis plasmáticos de ferro sérico e os valores de T2* no fígado, coração e pâncreas.

ABSTRACT Objectives: To evaluate the use of magnetic resonance imaging in patients with β-thalassemia and to compare T2* magnetic resonance imaging results with serum ferritin levels and the redox active fraction of labile plasma iron. Methods: We have retrospectively evaluated 115 chronically transfused patients (65 women). We tested serum ferritin with chemiluminescence, fraction of labile plasma iron by cellular fluorescence and used T2* MRI to assess iron content in the heart, liver, and pancreas. Hepatic iron concentration was determined in liver biopsies of 11 patients and the results were compared with liver T2* magnetic resonance imaging. Results: The mean serum ferritin was 2,676.5 +/- 2,051.7 ng/mL. A fraction of labile plasma iron was abnormal (> 0,6 Units/mL) in 48/83 patients (57%). The mean liver T2* value was 3.91 ± 3.95 ms, suggesting liver siderosis in most patients (92.1%). The mean myocardial T2* value was 24.96 ± 14.17 ms and the incidence of cardiac siderosis (T2* < 20 ms) was 36%, of which 19% (22/115) were severe cases (T2* < 10 ms). The mean pancreas T2* value was 11.12 ± 11.20 ms, and 83.5% of patients had pancreatic iron deposition (T2* < 21 ms). There was significant curvilinear and inverse correlation between liver T2* magnetic resonance imaging and hepatic iron concentration (r= −0.878; p < 0.001) and moderate correlation between pancreas and myocardial T2* MRI (r = 0.546; p < 0.0001). Conclusion: A high rate of hepatic, pancreatic and cardiac impairment by iron overload was demonstrated. Ferritin levels could not predict liver, heart or pancreas iron overload as measured by T2* magnetic resonance imaging. There was no correlation between liver, pancreas, liver and myocardial iron overload, neither between ferritin and fraction of labile plasma iron with liver, heart and pancreas T2* values

Lesão pulmonar aguda associada à transfusão (transfusion-related acute lung injury, TRALI) é uma complicação clínica grave relacionada à transfusão de hemocomponentes que contêm plasma. Recentemente, TRALI foi considerada a principal causa de morte associada à transfusão nos Estados Unidos e Reino Unido. É manifestada tipicamente por dispnéia, hipoxemia, hipotensão, febre e edema pulmonar não cardiogênico, que ocorre durante ou dentro de 6 h, após completada a transfusão. Embora o exato mecanismo não tenha sido totalmente elucidado, postula-se que TRALI esteja associada à infusão de anticorpos contra antígenos leucocitários (classes I ou II ou aloantígenos específicos de neutrófilos) e a mediadores biologicamente ativos presentes em componentes celulares estocados. A maioria dos doadores implicados em casos da TRALI são mulheres multíparas. TRALI, além de ser pouco diagnosticada, pode ainda ser confundida com outras situações de insuficiência respiratória aguda. Um melhor conhecimento sobre TRALI pode ser crucial na prevenção e tratamento desta severa complicação transfusional.

Transfusion-related acute lung injury (TRALI) is a serious clinical syndrome associated with the transfusion of plasma-containing blood components. Recently, TRALI has come to be recognized as the leading cause of transfusion-related death in the United States and United Kingdom. This complication typically presents as shortness of breath, hypoxemia, hypotension, fever and noncardiogeneic pulmonary edema, all occurring during or within 6 h after transfusion. Although the mechanism of TRALI has not been fully elucidated, it has been associated with human leukocyte antigen antibodies (class I, class II or neutrophil alloantigens) and with biologically active mediators in stored cellular blood components. Most of the donors implicated in cases of TRALI are multiparous women. Rarely diagnosed, TRALI can be confused with other causes of acute respiratory failure. Greater knowledge regarding TRALI on the part of clinicians could be crucial in preventing and treating this severe complication of blood transfusion.

Os filtros de leucócitos são eficazes em remover agentes infecciosos de hemocomponentes infectados. Neste estudo, foram avaliados os mecanismos de retenção de Trypanosoma cruzi (T. cruzi) por filtros de leucócitos. Amostras de concentrado de glóbulos vermelhos (CGV) e concentrado de plaquetas (CP) foram contaminados com parasitas T. cruzi (cepa Y, 3,4 x 10(6)/ml), e filtrados com filtros experimentais de leucócitos, com capacidade de remoção de aproximadamente 3 log10 leucócitos. A análise das fibras dos filtros através de microscopia eletrônica de transmissão mostrou que os parasitas T. cruzi foram removidos dos CGV e CP contaminados por mecanismo físico, sem interação com células sangüíneas. Além disso, foi demonstrado que os parasitas T. cruzi foram também removidos por adesão direta às fibras dos filtros, sugerindo um mecanismo biológico, provavelmente mediado por proteínas da superfície do parasita.

White cell (WBC)-reduction filters have been shown to be effective in removing infectious agents from infected blood products. In this study, the mechanisms of Trypanosoma cruzi (T. cruzi) retention by WBC-reduction filters were assessed. Human packed red blood cell (PRBC) and platelet concentrate (PC) samples were contaminated with T. cruzi organisms (Y strain; 3.4 x 10(6)/ml), and then filtered using WBC-reduction experimental filters that provided about 3 log10 WBC removal. Transmission electron microscopy sections showed that T. cruzi parasites were removed from contaminated PRBC and PC samples primarily by mechanical mechanism without interacting with filter fibbers or blood cells. In addition, we found that T. cruzi parasites were also removed by a direct fibber adhesion. These data indicate that T. cruzi parasites are removed from infected blood not only by mechanical mechanism but also by biological mechanism probably mediated by parasite surface proteins.

CONTEXTO: Pacientes com anemia falciforme recebem com freqüência concentrados de glóbulos vermelhos (CGV). Recentemente, nós relatamos que o risco de alo-imunização eritrocitária por unidade transfundida em pacientes brasileiros com anemia falciforme é 1,15%. RELATO DE CASO: Nós descrevemos uma reação transfusional hemolítica tardia (RTHT) apresentando-se como uma crise dolorosa em um paciente com anemia falciforme.

CONTEXT: Patients with sickle cell anemia (SCA) are frequently transfused with red blood cells (RBC). Recently, we reported that the calculated risk of RBC alloimmunization per transfused unit in Brazilian patients with SCA is 1.15%. We describe a delayed hemolytic transfusion reaction (DHTR) presenting as a painful crisis in a patient with SCA. CASE REPORT: A 35-year-old Brazilian female with homozygous SCA was admitted for a program of partial exchange transfusion prior to cholecystectomy. Her blood group was O RhD positive and no atypical RBC alloantibody was detected using the indirect antiglobulin technique. Pre-transfusional hemoglobin (Hb) was 8.7 g/dL and isovolumic partial exchange transfusion was performed using 4 units of ABO compatible packed RBC. Five days after the last transfusion she developed generalized joint pain and fever of 39°C. Her Hb level dropped from 12.0 g/dL to 9.3 g/dL and the unconjugated bilirrubin level rose to 27 mmol/L. She was jaundiced and had hemoglobinuria. Hemoglobin electrophoresis showed 48.7% HbS, 46.6% HbA1, 2.7% HbA2, and 2.0% HbF. The patient’s extended RBC phenotype was CDe, K-k+, Kp(a-b+), Fy(a-b-), M+N+s+, Le(a+b-), Di(a-). An RBC alloantibody with specificity to the Rh system (anti-c, titer 1:16.384) was identified by the indirect antiglobulin test. The Rh phenotype of the RBC used in the last packed RBC transfusion was CcDEe. The patient was discharged, asymptomatic, 7 days after admission.