Assessment of Iron Overload in Very Young Children with Limited Thalassemia Care Resources in South China

Abstract

Southern China has one of the world's largest population of patients needing transfusions. Transfusion and chelation are not uniformly available and no magnetic resonance imaging (MRI) assessment data exists to date. A total of 153 young β-thalassemia major (β-TM) patients were assessed using a validated 1.5T scanner in Hong Kong, People's Republic of China (PRC). Their median age was 13 (range 7 to 30), and most patients were young (22.0% age <10, 73.0% age <15, 88.0% age <18). Erratic health care made estimation of total transfusion and chelation exposure impossible. Despite their early age, 24.0% had severe cardiac hemosiderosis [T2*<10 milliseconds (ms)], at ages as early as 8 years old. Median heart iron was 1.68 mg/g dry weight (range 0.19-7.66) and increased with age (p = 0.017), while liver iron was 22.2 mg/g dry weight (range 3.15 to 39.2). Serum ferritin levels were poor predictors of heart and liver, or pancreatic R* and pituitary R* values. Magnetic resonance imaging scans are needed to screen very young β-TM patients with immediate risk of premature cardiac death in developing nations and triage them to more intensive treatment. This is particularly important in countries with a large number of patients and limited resources. Our data suggests that in developing countries, there is no lower limit for thalassemia MRI scanning programs.

Value of severe liver iron overload for assessing heart iron levels in thalassemia major patients

“…While in the studies that reported significant correlations between liver and heart iron, the number and proportion of severe LIO patients were high . In the study by Au et al, severe liver iron loading was found in the majority of patients (accounting for 55.0%; n = 153). In our study, 64 patients had severe LIO, accounting for 58.18%, which is similar to that of Au et al Meanwhile, from the curve fit acquired, poor correlation between liver and heart iron in the normal or mild LIO segments can be clearly seen, whereas they had a close relationship in the severe LIO segment.…”

“…Some studies reported that liver iron levels had no significant linear correlations with heart iron . But other studies reported that significant correlations existed between them . One possible explanation that can reconcile this disparity is that a delay exists in the loading and unloading of heart iron with respect to liver iron .…”

“…We thus believe that LIO deserves further investigation to determine whether a correlation exists when liver iron deposition is severe. In some studies with severe liver iron overload patients, the authors did not fully investigate correlations between severe LIO and heart iron levels . Moreover, the clinical course of these patients is still unclear, i.e., when severe iron overload is present in the liver, should aggressive therapy be used for patients without HIO?…”

Correlation between Serum Ferritin and Cardiac Troponin I in Major Beta Thalassemia Children

“…Statistics analyses by t test showed significant differences in serum ferritin levels between the MBT and control groups (p value = 0.0004). A study in China also found high serum ferritin levels in MBT patients, 2754 µg/L [16]. Another study on Egyptian children with MBT also found high serum ferritin levels, 4510 µg/L [17].…”

Modified conditioning regimen improves outcomes of unrelated donor peripheral blood stem cell transplantation for β‐thalassaemia major patients

“…Currently, it is particularly difficult to identify compatible donors in China due to the nation's one‐child policy. Moreover, many patients with TM cannot financially afford long‐term supportive care with normative blood transfusions and iron chelation . Thus, although thalassaemia‐free survival (TFS) rates have increased to 52–82% following HSCT, an alternative source of donors is urgently needed.…”