ABSTRACT
Management of Beta (β)-thalassaemia intermedia in contrast to β-thalassaemia major patients has no clear guidelines as to indicators of adequate transfusion. Regular blood transfusion suppresses bone marrow erythropoietic activity. Serum soluble transferrin receptor (sTfR) concentration is a marker for erythropoietic activity, with increased sTfR being associated with functional iron defi ciency and increased erythropoietic activity. This study aimed to determine the use of sTfR as an indicator of adequate transfusion in adult β-thalassaemia intermedia patients. A cross-sectional study was conducted at Hospital Ampang, Malaysia, for six months. Patient group included six β-thalassaemia intermedia and 34 HbE-β-thalassaemia transfused patients. None of the patients were on regular monthly blood transfusions as in β-thalassaemia major. The control group comprised of 16 healthy subjects with normal haematological parameters. Haemoglobin (Hb) analysis, sTfR and ferritin assays were performed. Hb and HbA percentages (%) were found to be signifi cantly lower in patients compared to the controls, while HbE%, HbF%, sTfR and ferritin were signifi cantly higher in patients. An inverse relationship was found in the controls between HbF% with Hb (r = -0.515, p < 0.05) and HbA% (r = -0.534, p < 0.05). In patients, sTfR showed an inverse relationship with HbA% (r = -0.618, p = 0.000) and a positive correlation with HbE% (r = 0.418, p = 0.007) and HbF% (r = 0.469, p = 0.002). Multivariate analysis showed that HbA% (r = 2.875, p = 0.048), HbE% (r = 2.872, p = 0.020) and HbF% (r = 2.436, p = 0.013) best predicted sTfR independently in patients. Thus, sTfR is a useful marker for erythropoiesis. The elevated sTfR in these patients indicate that the transfusion regimen used was inadequate to suppress ineffective erythropoiesis. Hb levels may not be the best target for monitoring transfusion treatment in β-thalassaemia intermedia patients, but the use of sTfR is helpful in individualising transfusion regimens.
ABSTRACT
Introduction: HbE is the commonest beta haemoglovin (Hb) variant in Southeast Asia. It causes a reduction in synthesis of beta-globin E (βE) chain. Studies indicate HbE coinherited with α-thalassaemia leads to a milder clinical phenotype. This study investigates the concomitant inheritance of α-thalassaemia in Malays with HbE. Methods: Four hundred and fourteen (414) blood samples were screened for haemoglobinopathy using primarily the first 3 steps of the BHES [(B) blood counts, blood film: (H), HPLC; (E),elstrophoresis; (S),stability)] protocol. Complete blood counts were generated on an automated blood cell analyser, HB typing with cation exchange high-performance liquid chromatography (HPLC) and Hb typing with cation exchange high-performance liquid chromatography (HPLC) and Hb electrophoresis at an alkaline pH (pH 8.5). Forty-five (10.9%) were identified as HbE trait and DNA analysis was done for deletional α-thalassaemia using a single-tube multiplex-PCR assay. Results: Among the 45 subjects with HbE trait. 4 (8.9%) were found to have alpha-thalassaemia-2 (α⁺) (α-3.7 kb deletion) and 1 (2.2%) the alpha-thalassaemia-1 (α⁰) (—SEA 20.5kb deletion) defects respectively. Discussion: These findings show that 11.1% of Malays with HbE inherit alpha-thalassaemia concurrently. The most prevalent interaction found was a double heterozygote for HbE/α-thalassaemia 2, followed by HbE/α-thalassaemia 1. Conclusion: Molecular screening of deletional α-thalassaemia identified its concurrent inheritance in 11.1% of Malays who were HbE carriers. This information will guide genetic counseling and the planning of treatment modalities in patients with HbE alpha-thalassaemia.