title: Presence of the IVS-I-6-Mutated Allele in Beta-Thalassemia Major Patients Correlates with Extramedullary Hematopoiesis Incidence.
abstract: Extramedullary hematopoiesis (EMH) results from the extension of hematopoietic tissue beyond the confines of the bones. Since the initiation of regular transfusion programs from an early age for all thalassemia major (ΤΜ) patients, EMH has not been considered a clinical issue anymore. The present study aims to record the prevalence of EMH in chronically transfused ΤΜ patients followed at our institution and to investigate possible risk factors associated with its occurrence. The project was designed as a retrospective, nonexperimental, descriptive, exploratory study. In total, the study enrolled 104 patients. EMH was revealed in 15/104 (14%) patients. The presence of intravening sequence (IVS)-I-6 was significantly related with the development of EMH (p < 0.05). No other demographic or biological factor studied was found to be related with the presence of EMH. The study stresses a profound incidence of asymptomatic EMH in a solid group of well-transfused ΤΜ patients. Given the high incidence of the IVS-I-6 allele in the Mediterranean and Middle Eastern region, high-quality, prospective, multicenter studies could confirm the association of EMH occurrence with the presence of the IVS-I-6 mutation and further evaluate the exact role of this mutation in the EMH process.
authors.affiliation: Adult Thalassemia Unit, Second Department of Internal Medicine, Aristotle University of Thessaloniki, Ippokrateio General Hospital of Thessaloniki, Thessaloniki, Greece.
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Sousos
authors.forename: Despoina
authors.initials: D
authors.lastname: Adamidou
authors.forename: Philippos
authors.initials: P
authors.lastname: Klonizakis
authors.forename: Alexandra
authors.initials: A
authors.lastname: Agapidou
authors.forename: Stamatia
authors.initials: S
authors.lastname: Theodoridou
authors.forename: Georgios
authors.initials: G
authors.lastname: Spanos
authors.forename: Kyriakos
authors.initials: K
authors.lastname: Psarras
authors.forename: Evaggelia
authors.initials: E
authors.lastname: Vetsiou
authors.forename: Timoleon-Achilleas
authors.initials: TA
authors.lastname: Vyzantiadis
authors.forename: Efthymia
authors.initials: E
authors.lastname: Vlachaki
mesh_terms: D000328:Adult; D000483:Alleles; D005260:Female; D005838:Genotype; D006115:Greece / Q000453:epidemiology; D006411:Hematopoiesis, Extramedullary / Q000235:genetics*; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009154:Mutation; D012189:Retrospective Studies; D012307:Risk Factors; D055815:Young Adult; D055544:beta-Globins / Q000235:genetics*; D017086:beta-Thalassemia / Q000453:epidemiology / Q000235:genetics* / Q000473:pathology*
chemical_list: D055544:beta-Globins
keywords: Extramedullary hematopoiesis; IVS-I-6 genotype; Thalassemia major