title: Vascular dysfunction in patients with young β-thalassemia: relation to cardiovascular complications and subclinical atherosclerosis.
abstract: We aimed to study the endothelial dysfunction among children and adolescents with transfusion-dependent β-thalassemia using von Willebrand factor antigen (VWF:Ag) and flow cytometric analysis of circulating CD144(+) endothelial microparticles (EMPs) and endothelial progenitor cells (CD34(+)VEGFR2(+)) and assess their relation to iron overload, erythropoietin and chelation therapy as well as echocardiographic parameters and carotid intima-media thickness. The VWF:Ag, EMPs, and CD34(+)VEGFR2(+) cells were significantly higher among patients with β-thalassemia than controls (P < .001). The type of chelation and patients' compliance did not influence the results. No significant correlations were found between the studied vascular markers. Patients with evident heart disease had higher VWF: Ag, EMPs, and CD34(+)VEGFR2(+) cells than those without. Carotid intima-media thickness was increased among patients but not correlated with vascular markers. We suggest that procoagulant EMPs and VWF: Ag are involved in cardiovascular complications in patients with young β-thalassemia. CD34(+)VEGFR2(+) cells were further increased in response to tissue injury contributing to reendothelialization and neovascularization.
authors.affiliation: Pediatrics Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt amiradiabetes@yahoo.com.
authors.forename: Amira Abdel Moneam
authors.initials: AA
authors.lastname: Adly
authors.affiliation: Pediatrics Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt.
authors.forename: Nayera Hazaa
authors.initials: NH
authors.lastname: El-Sherif
authors.affiliation: Clinical Pathology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt.
authors.forename: Eman Abdel Rahman
authors.initials: EA
authors.lastname: Ismail
authors.affiliation: Radiology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt.
authors.forename: Yosra Abd
authors.initials: YA
authors.lastname: El-Zaher
authors.affiliation: Clinical Pathology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt.
authors.forename: Amal
authors.initials: A
authors.lastname: Farouk
authors.affiliation: Pediatrics Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt.
authors.forename: Asmaa Mohamed
authors.initials: AM
authors.lastname: El-Refaey
authors.affiliation: Pediatrics Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt.
authors.forename: Mohammed Samy
authors.initials: MS
authors.lastname: Wahba
mesh_terms: D000293:Adolescent; D015703:Antigens, CD / Q000097:blood; D050197:Atherosclerosis / Q000097:blood / Q000209:etiology / Q000473:pathology; D015820:Cadherins / Q000097:blood; D059168:Carotid Intima-Media Thickness; D055252:Cell-Derived Microparticles / Q000378:metabolism / Q000473:pathology; D002648:Child; D042783:Endothelial Cells / Q000378:metabolism / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D013234:Stem Cells / Q000378:metabolism / Q000473:pathology; D017086:beta-Thalassemia / Q000097:blood / Q000150:complications / Q000473:pathology; D000099152:Cadherin 5
chemical_list: D015703:Antigens, CD; D015820:Cadherins; D000099152:Cadherin 5
keywords: endothelial microparticles; endothelial progenitor cells; erythropoietin; thalassemia; vascular dysfunction; von Willebrand factor antigen