Iron overload in Brazilian thalassemic patients

• Main Authors: Reijane Alves de Assis, Fernando Uliana Kay, Laércio Alberto Rosemberg, Alexandre Henrique C. Parma, Cesar Higa Nomura, Sandra Regina Loggetto, Aderson da Silva Araujo, Antonio Fabron Junior, Mônica Pinheiro de Almeida Veríssimo, Giorgio Roberto Baldanzi, Merula A. Steagal, Claudia Angela Galleni Di Sessa Velloso, Breno Pannia Espósito, Sandra Saemi Nakashima, Michelli da Silva Diniz, Fernando Tricta, Ronaldo Hueb Baroni, Marcelo Buarque de Gusmão Funari, John C. Wood, Andreza Alice Feitosa Ribeiro, Nelson Hamerschlak
• Format: Article
• Language: English
• Published: Instituto Israelita de Ensino e Pesquisa Albert Einstein 2011-06-01
• Series: Einstein (São Paulo)
• Subjects: Blood transfusion; Magnetic resonance imaging; Biopsy; Iron overload
• Online Access: http://apps.einstein.br/revista/arquivos/PDF/1897-Einstein_v9n2_165-172.pdf

Objectives: To evaluate the use of magnetic resonance imaging inpatients with β-thalassemia and to compare T2* magnetic resonanceimaging 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.