Evaluation of the effect of eltrombopag therapy on the platelet collagen receptor glycoprotein VI (GPVI) expression and soluble GPVI levels in young patients with immune thrombocytopenia.

BACKGROUND: Platelet glycoprotein VI (GPVI) receptor is essential for platelet adhesion and aggregation. Eltrombopag is as an effective treatment for chronic immune thrombocytopenia (ITP); yet, its effect on platelet function is not fully characterized. AIM: This prospective study investigated the effect of eltrombopag therapy on platelet function through assessment of GPVI receptor expression and soluble GPVI levels among pediatric patients with persistent or chronic ITP. METHODS: Thirty-six children and adolescents with persistent or chronic ITP were divided equally into two groups either to receive eltrombopag therapy or the standard of care. All patients were followed-up for 12 months with assessment of bleeding score and complete blood count (CBC). Evaluation of GPVI expression using flow cytometry and measurement of its soluble form by ELISA was done at baseline and at 6 months. RESULTS: ITP patients on eltrombopag had significantly lower bleeding score after 6 months of therapy while the quality of life has significantly improved. Platelet count was significantly increased throughout the study. GPVI expression by flow cytometry and soluble GPVI levels were significantly increased after eltrombopag therapy. After 12 months, ITP patients on eltrombopag were able to maintain a good quality of life and low bleeding score. CONCLUSION: Our data suggest that eltrombopag, through its effect on the GPVI receptor expression and its soluble form, might reduce bleeding manifestations and improve the quality of life of chronic and persistent ITP children independent of its effect on the platelet count.

Ischemia-modified albumin as a marker of vascular dysfunction and subclinical atherosclerosis in ß-thalassemia major.

BACKGROUND: Ischemia-modified albumin (IMA) is an altered type of serum albumin that forms under conditions of oxidative stress and an independent predictor of major adverse cardiovascular events. OBJECTIVES: To measure the levels of IMA in 45 children and adolescents with ß-thalassemia major (ß-TM) compared with 30 healthy controls and assess its relation to lipid peroxidation, vascular complications and subclinical atherosclerosis. METHODS: ß-TM patients without symptoms of heart disease were studied focusing on transfusion history, chelation therapy, serum ferritin, malondialdehyde (MDA) and IMA levels. Echocardiography was performed and carotid intima media thickness (CIMT) was assessed. RESULTS: IMA and MDA levels were significantly higher in ß-TM patients compared with controls (p < 0.001). IMA was higher among patients with heart disease, pulmonary hypertension risk and serum ferritin ≥2500 µg/l than those without. TM patients compliant to chelation had significantly lower IMA levels. IMA levels were positively correlated to MDA and CIMT while negatively correlated to ejection fraction and fractional shortening. CONCLUSION: Our results highlight the role of oxidative stress in the pathophysiology of vascular complications in thalassemia. IMA could be useful for screening of ß-TM patients at risk of cardiopulmonary complications and atherosclerosis because its alteration occurs in early subclinical disease.