Hypothyroidism in children with Hb E/ß-thalassemia compared between those who received regular transfusion and those who underwent hematopoietic stem cell transplantation.

The studies of hypothyroidism in children with transfusion-dependent hemoglobin E/ß-thalassemia (TDT), especially in those who underwent hematopoietic stem cell transplantation (HSCT) are limited. We performed a longitudinal retrospective analysis of thyroid function test (TFT) results among TDT patients aged <25 years who received regular transfusion compared to those who underwent HSCT in Faculty of Medicine Siriraj hospital, Thailand during October 2003 to March 2019. Fifty patients (23 TDT, 27 HSCT) were included. The mean age at the last follow-up was 20.1 ± 2.8 vs. 14.5 ± 4.61 years, respectively. The median age at HSCT was 6 (range: 1.9-13.7) years. The prevalence of hypothyroidism among TDT and post-HSCT was 47.8% and 52.2%, respectively. No study patients showed symptoms or signs of hypothyroidism. Subclinical hypothyroidism was the most common type (63.6% of TDT, and 100% of post-HSCT). We found persistent hypothyroidism in 30.4% of TDT, and in 22.2% of post-HSCT. Thyroxine was given in 1 TDT patient with overt hypothyroidism, and in 3 of 6 post-HSCT patients with persistent subclinical hypothyroidism. The ex-thalassemia patients who underwent HSCT after the age of 10 years had a significantly higher risk of post-HSCT hypothyroidism compared to those who underwent HSCT at the age ≤10 years (hazard ratio: 12.01, 95% confidence interval: 1.65-87.41; p = 0.014). In conclusion, hypothyroidism was found to be common in both TDT and post-HSCT patients. Subclinical hypothyroidism without symptoms and signs was the most common type, and was diagnosed only by TFT screening. Long-term regular surveillance of TFT should be performed in both groups of patients.

Differences in longitudinal growth patterns of children and adolescents with transfusion-dependent hemoglobin E/ß-thalassemia and those achieving successful hematopoietic stem-cell transplantation.

BACKGROUND: Short stature is a very common endocrinopathy among children with transfusion-dependent (TD) thalassemia. Hematopoietic stem-cell transplantation (HSCT) is the only effective curative treatment for TD thalassemia. This study aimed to identify and compare the longitudinal growth patterns of children with TD hemoglobin E (Hb E)/ß-thalassemia against those of children successfully undergoing HSCT. MATERIALS AND METHODS: We reviewed the medical records of 39 patients with TD Hb E/ß-thalassemia receiving regular blood transfusions, and 39 post-HSCT patients. Longitudinal weight and height Z-scores at each year of age were recorded for TD patients, and longitudinal weight and height Z-scores at each year before and after HSCT were obtained for post-HSCT patients. RESULTS: The mean weight and height Z-scores of TD patients decreased gradually and were lowest at age 13. However, post-HSCT subjects saw significant improvement in their mean weight and height Z-scores 6 and 3 years after HSCT, respectively, relative to pre-HSCT baseline values. CONCLUSIONS: Longitudinal growth patterns differed between patients successfully undergoing HSCT and children and adolescents with TD Hb E/ß-thalassemia. HSCT significantly improved height outcomes of children and adolescents with TD Hb E/ß-thalassemia.