Prevalence of growth and endocrine disorders in Malaysian children with transfusion-dependent thalassaemia

INTRODUCTION: Endocrine dysfunction due to iron overload secondary to frequent blood transfusions is a common complication in children with transfusion-dependent thalassaemia (TDT). We ascertained the prevalence of endocrine dysfunction in children with TDT seen in a hospital setting in Malaysia.

METHODS: We reviewed all patients with TDT who had ≥ 8 blood transfusions per year. Patients who had a history of stem cell transplantation, concurrent autoimmune diseases or were newly diagnosed to have TDT were excluded. Standard diagnostic criteria were used in the diagnosis of various endocrine dysfunctions.

RESULTS: Of the 82 patients with TDT, 65% had at least one endocrine dysfunction. Short stature was the commonest (40.2%), followed by pubertal disorders (14.6%), hypoparathyroidism (12.3%), vitamin D deficiency (10.1%), hypocortisolism (7.3%), diabetes mellitus (5.2%) and overt hypothyroidism (4.9%). Subclinical hypothyroidism and pre-diabetes mellitus were seen in 13.4% and 8.6% of the patients, respectively. For children aged < 10 years, the prevalence of both thyroid dysfunction and hypoparathyroidism was 9.1%.

CONCLUSION: Two-thirds of children with TDT experienced at least one endocrine dysfunction. Thyroid dysfunction and hypoparathyroidism may be missed if endocrine screening is only performed in children with TDT > 10 years of age. Close monitoring for endocrine dysfunction and hormonal therapy is essential to prevent long-term adverse outcomes.