Comparison of organ dysfunction in transfused patients with SCD or β thalassemia

Abstract

Although it is life saving, transfusion therapy has resulted in the majority of sickle cell anemia and thalassemia patients being at risk for hemosiderosis-induced organ damage. It is unknown whether the complications of iron overload are affected by the underlying disease. In order to address this problem, we compared the prevalence of organ dysfunction in both groups of patients receiving chronic transfusion therapy (b thalassemia, N = 30; sickle cell anemia, N = 43). Both groups had similar quantitative liver iron. Thalassemia patients had greater cardiac disease (20% vs. 0%), growth failure (27% vs. 9%), and endocrine failure (37% vs. 0%). The strongest predictors of combined endocrine and cardiac disease in multivariate analysis were duration of chronic transfusion (P = 0.03) and diagnosis (P = 0.03). Quantitative liver iron concentration on a single liver biopsy was not predictive of cardiac or endocrine injury. Viral hepatitis is the strongest predictor of hepatocellular damage (P = 0.009), while the development of liver fibrosis is more closely related to liver iron concentration (P = 0.04). In conclusion, sickle cell anemia and thalassemia differ in the prevalence of organ injury. This difference is related to the duration of iron exposure and the specific hemoglobinopathy. A prospective study with a larger number of subjects is needed to confirm the relationships between specific diagnosis, liver iron concentration over time, and organ dysfunction. Am.

Total antioxidant capacity in Mediterranean β-thalassemic patients

“…1 Nevertheless, iron overload remains a common complication, especially after long-term treatment. 2,3 On the one hand, it has been evident from previous studies that iron overload is the main causative agent responsible for the increased production of free radicals and reactive oxygen species (ROS), and the subsequent oxidative stress which is compensated for by various antioxidants present in the body. 4 Oxidative stress occurs as a result of increased levels of lipid peroxides and free-radical intermediates, along with a decrease in total antioxidant capacity (TAC).…”

Early Cardiac Iron Overload in a Child on Treatment of Acute Lymphoblastic Leukemia

“…9,12 For example, patients with thalassemia major transfused every 3 weeks require nearly 10 years to demonstrate cardiac iron loading. 13 Patients with sickle cell disease compared with thalassemia major patients with equal duration and magnitude of iron loading exhibit much less iron-related cardiotoxicity 14 and only ∼2.5% ultimately develop cardiac iron. 4 In contrast, patients with DiamondBlackfan anemia or congenital dyserythropoietic anemia receiving transfusions demonstrate cardiac iron deposition much earlier, within ∼2 years, 9 a difference attributable to their relatively higher NTBI levels.…”

Iron chelation therapy for patients with sickle cell disease and iron overload

“…Furthermore, extensive studies in regularly transfused patients with b-thalassemia major have identified heart failure as the leading cause of death due to iron accumulation in the myocardium [43,44]. While cardiac decompensation and cardiomyopathy are known clinical manifestations in patients with SCD, magnetic resonance imaging (MRI) T2* evaluation of cardiac iron load in patients with SCD has indicated lower levels of iron accumulation despite similar transfusion burdens [42,45,46]. A similar situation is seen with iron overloadassociated endocrinopathy, which has been shown to be common in patients with b-thalassemia major but rarely reported in the population of patients with SCD [42,47].…”

“…The distribution and consequences of iron overload in patients with SCD have been shown to differ compared with patients with b-thalassemia major. Although the liver is the primary site of excess iron storage in both patients with SCD and b-thalassemia major, with LIC correlating significantly with the duration of transfusions, there are some disparities in the occurrence of organ injury [41,42]. Furthermore, extensive studies in regularly transfused patients with b-thalassemia major have identified heart failure as the leading cause of death due to iron accumulation in the myocardium [43,44].…”

“…While cardiac decompensation and cardiomyopathy are known clinical manifestations in patients with SCD, magnetic resonance imaging (MRI) T2* evaluation of cardiac iron load in patients with SCD has indicated lower levels of iron accumulation despite similar transfusion burdens [42,45,46]. A similar situation is seen with iron overloadassociated endocrinopathy, which has been shown to be common in patients with b-thalassemia major but rarely reported in the population of patients with SCD [42,47]. There are several hypotheses to explain these distinct differences in iron loading and organ toxicity, including differences in the rate and duration of transfusions as well as the possibility that the chronic inflammatory state associated with SCD is protective against tissue damage [48].…”