Iron overload status in patients with non-transfusion-dependent thalassemia in China

Magnetic Resonance Evaluation of Tissue Iron Deposition and Cardiac Function in Adult Regularly Transfused Thalassemia Intermedia Compared with Thalassemia Major Patients

Objectives: This multicenter, retrospective, population-based, matched-cohort study compared clinical characteristics and magnetic resonance imaging (MRI) findings, including hepatic, pancreatic, and cardiac iron levels and cardiac function, between 135 adult regularly transfused thalassemia intermedia (TI) patients (44.73 ± 12.16 years, 77 females) and 135 age- and sex-matched thalassemia major (TM) patients (43.35 ± 9.83 years, 77 females), enrolled in the Extension-Myocardial Iron Overload in Thalassemia Network. Methods: The MRI protocol included the quantification of hepatic, pancreatic, and cardiac iron levels (R2* technique), the assessment of biventricular function parameters (cine images), and the detection of replacement myocardial fibrosis (late gadolinium enhancement technique). Results: Age, sex, frequency of splenectomy and chelation, and serum ferritin levels were not significantly different (p > 0.05) between the two groups, but TI patients started regular transfusions significantly later (p < 0.0001) and showed significantly lower pre-transfusion hemoglobin levels (p = 0.005). No difference was found in hepatic iron levels (p = 0.853). TI patients exhibited significantly lower pancreatic R2* values (p < 0.0001), also correcting for the duration of regular transfusions, and significantly lower cardiac R2* values (p < 0.0001). In the receiver operating characteristic analysis, pancreatic iron was the strongest discriminator between the two diseases. Left and right ventricular end-diastolic volume indexes were significantly higher in TI than in TM patients (p = 0.003 and p = 0.046, respectively), but the correction for the duration of regular transfusions removed the disease-specific differences (p > 0.05). Left ventricular (LV) mass index was significantly higher in TI (p = 0.049), while no difference (p > 0.05) was found in biventricular ejection fractions and replacement myocardial fibrosis. Conclusions: TI patients showed lower pancreatic and cardiac iron burden and more pronounced LV hypertrophy. These differences could not be explained by the different duration of the transfusional regimen.

Compound heterozygosity for Southeast Asian hereditary persistence of fetal hemoglobin and β0-thalassemia results in thalassemia intermedia: Pedigree analysis and genetic research in a family from South China. A case report

RATIONALE

Compound heterozygotes for deletional β-thalassemia can be difficult to diagnose due to its diverse clinical presentations and no routine screenings. This can lead to disease progression and delay in treatment.

PATIENT CONCERNS

We reported pedigree analysis and genetic research in a family with rare β-thalassemia.

DIAGNOSIS

Pedigree analysis and genetic research demonstrated that the patient was a compound heterozygote for β-thalassemia CD17/Southeast Asian hereditary persistence of fetal hemoglobin deletion, inherited from the parents. Magnetic resonance imaging T2* examination revealed severe iron deposition in the liver. Echocardiography revealed endocardial cushion defect.

INTERVENTIONS

The patient was treated with Deferasirox after receiving the final molecular genetic diagnosis. The initial once-daily dose of Deferasirox was 20 mg/kg/d.

OUTCOMES

The patient discontinued the medication three months after the first visit. Two years later, the patient visited the Department of Hepatobiliary and Pancreatic Diseases. He was recommended to undergo splenectomy after surgical repair of the congenital heart disease. However, the patient refused surgical treatment because of the economic burden.

LESSONS

We report that fetal hemoglobin is a sensitive indicator for screening large deletions of the β-globin gene, which can be effectively confirmed by the multiplex ligation-dependent probe amplification assay. In non-transfusion-dependent thalassemia patients, iron status assessment should be regularly performed, and iron chelation treatment should be initiated early. This case will provide insights for the diagnosis of rare genotypes of β-thalassemia and has important implications for genetic counseling.

Αlpha-thalassemia: A practical overview

α-Thalassemia is an inherited blood disorder characterized by decreased synthesis of α-globin chains that results in an imbalance of α and β globin and thus varying degrees of ineffective erythropoiesis, decreased red blood cell (RBC) survival, chronic hemolytic anemia, and subsequent comorbidities. Clinical presentation varies depending on the genotype, ranging from a silent or mild carrier state to severe, transfusion-dependent or lethal disease. Management of patients with α-thalassemia is primarily supportive, addressing either symptoms (eg, RBC transfusions for anemia), complications of the disease, or its transfusion-dependence (eg, chelation therapy for iron overload). Several novel therapies are also in development, including curative gene manipulation techniques and disease modifying agents that target ineffective erythropoiesis and chronic hemolytic anemia. This review of α-thalassemia and its various manifestations provides practical information for clinicians who practice beyond those regions where it is found with high frequency.

Non-Transfusion-Dependent Thalassemia: A Panoramic Review

Non-transfusion-dependent thalassemia (NTDT) has been considered less severe than its transfusion-dependent variants. The most common forms of NTDT include β-thalassemia intermedia, hemoglobin E/beta thalassemia, and hemoglobin H disease. Patients with NTDT develop several clinical complications, despite their regular transfusion independence. Ineffective erythropoiesis, iron overload, and hypercoagulability are pathophysiological factors that lead to morbidities in these patients. Therefore, an early and accurate diagnosis of NTDT is essential to ascertaining early interventions. Currently, several conventional management options are available, with guidelines suggested by the Thalassemia International Federation, and novel therapies are being developed in light of the advancement of the understanding of this disease. This review aimed to increase clinicians’ awareness of NTDT, from its basic medical definition and genetics to its pathophysiology. Specific complications to NTDT were reviewed, along with the risk factors for its development. The indications of different therapeutic options were outlined, and recent advancements were reviewed.