Effects of thalidomide on endothelial activation and stress index in children with β-thalassemia major

To the editor.-thalassemia major (TM) is a congenital hemolytic disease characterized by reduced or absent -globin production, hemolysis from resulting unstable -globin tetramers, ineffective erythropoiesis, and severe anemia that is fatal in the absence of life-long red cell transfusions. 1Hematopoietic stem cell transplantation (HSCT) remains the only curative option, achieving thalassemia-free survival rates as high as 97%. 2 However, HSCT presents various risks, particularly in older children and those without a fully matched donor, limiting its widespread use.The Endothelial Activation and Stress Index (EASIX) is a biomarker calculated using lactate dehydrogenase (LDH), creatinine, and platelet counts and is significantly associated with complications and mortality after transplantation. [3][4]][5][6] Thalidomide, known for inducing fetal hemoglobin production, can effectively increase hemoglobin levels in TM patients, often serving as a bridging treatment.However, the impact of pre-transplant thalidomide treatment on transplant outcomes remains uncertain.This study evaluates the changes in EASIX following thalidomide treatment in children with TM.We retrospectively assessed children with TM who received thalidomide for more than three months between May 2021 and June 2024.The study included 25 patients (15 males and 10 females) aged 14-18 years.The EASIX score was calculated using LDH (U/L) creatinine (mg/dL) / platelet count (10 9 /L) from laboratory data recorded after approximately three months of thalidomide treatment.A significant reduction in EASIX was observed in TM patients posttreatment (p=0.002)(Figure 1).We investigated the correlations between EASIX and baseline indicators.In addition to platelets (r=-0.601,p=0.001),LDH (r=0.536,p=0.006), and creatinine (r=0.595,p=0.002),EASIX was inversely correlated with white blood cell count (r=-0.450,p=0.024) and positively correlated with total bilirubin (r=0.615,p=0.001) and indirect bilirubin (r=0.561,p=0.004).