HEMOGLOBIN H DISEASE AND GROWTH: A COMPARATIVE STUDY OF DHbH AND NDHbH PATIENTS

Abstract

Background: Hemoglobin H disease (HbH), a hemoglobinopathy resulting from abnormal alpha globin genes, is classified into two categories: deletional HbH (DHbH) and non-deletional HbH (NDHbH). The alpha-mutation genotypes exhibit a range of clinical anemias, which differentially impact patient growth.
 Objectives: This retrospective study assessed the growth of HbH patients at Siriraj Hospital, Mahidol University.
 Methods: Patients diagnosed with HbH between January 2005 and April 2021 were analyzed using growth standard scores of the Thai Society for Pediatric Endocrinology (2022 version) and BMI-for-age Z scores of the World Health Organization. Growth failure was defined as a patient’s height for age exceeding two standard deviations below the mean.
 Results: Of the 145 HbH patients, 75 (51.7%) had NDHbH, with --SEA/αCSα being the most common genotype (70 patients; 93.3%). The mean baseline hemoglobin level was significantly lower in NDHbH patients than in DHbH patients (8.16 ± 0.93 g/dL vs. 9.51 ± 0.68 g/dL; P < 0.001). Splenomegaly and growth failure prevalences were higher in NDHbH patients (37.3% vs. 0%, with P < 0.001, and 22.7% vs. 8.6%, with P = 0.020, respectively). Multivariable analysis revealed that splenomegaly > 3 cm was associated with growth failure (OR = 4.28; 95% CI, 1.19–15.39; P = 0.026).
 Conclusions: NDHbH patients exhibited lower hemoglobin levels and more pronounced splenomegaly than DHbH patients. Growth failure can occur in both HbH types but appears more prevalent in NDHbH. Close monitoring of growth velocity is essential, and early treatment interventions may be required to prevent growth failure.

A case of congenital dyserythropoietic anemia masked by hemoglobin H disease

“…Both CDA and HbH disease are congenital anemias with ineffective hematopoiesis, but their co-occurrence is very rare. 2 , 3 Here, we report the case of a Chinese boy with CDA II, which was masked by HbH disease, and discuss the clinical course.…”

“…HbH disease is the most common form of α-thalassemia syndrome, resulting from compound heterozygosity of α-thalassemia due to a loss of two linked α-globin genes and either a single α-gene deletion or a non-deletional mutation on the other alleles. 3 , 4 Instability and oxidization ability of the β-chain tetramer produce intracellular precipitates that affect the integrity of the red cell membrane in early erythroid cells, leading to ineffective erythropoiesis and erythroid cell death, which in turn eventually cause acute hemolytic anemia, marked microcytosis, and hypochromia. When combined with β-thalassemia, the symptoms of HbH can be reduced, and the detection of HbH bands may decrease.…”

Protein S deficiency with recurrent thromboembolism in a patient with hemoglobin H disease following splenectomy

“…Splenectomy is an effective treatment for hemoglobin H (HbH) disease; however, thromboembolic events (TEEs) frequently occur in patients with thalassemia following splenectomy. 1 , 2 The pathogenic mechanisms may involve the chronic hypercoagulable state observed in patients with thalassemia without a spleen, including thrombocytosis, chronic platelet activation, and perturbation of the red blood cell membrane. 3 , 4 Reports of recurrent thromboembolism in patients with HbH disease associated with congenital thrombophilic mutations are scarce.…”