title: Extramedullary haematopoiesis correlates with genotype and absence of cardiac iron overload in polytransfused adults with thalassaemia.
abstract: BACKGROUND
  The mechanisms responsible for the sporadic occurrence of extramedullary haematopoiesis in polytransfused thalassaemic patients have not yet been clarified. In this study we tried to elucidate the influence of genotype and other factors on the presence of extramedullary haematopoiesis.
  
  
  METHODS
  We performed a retrospective database review of our polytransfused thalassaemic patients between January 2006 and December 2011. Demographic, transfusional, genetic, radiological and biochemical data were collected and statistically analysed.
  
  
  RESULTS
  Extramedullary haematopoiesis was found in 18 out of 67 patients (27%). All of them were splenectomised, had a higher nucleated red blood cell count and higher levels of the soluble form of transferrin receptor with respect to patients without extramedullary haematopoiesis; furthermore, patients with EMH had a lower transfusional iron intake and a higher pre-transfusion haemoglobin level as compared with those without extramedullary haematopoiesis. Ten out of the 18 patients with extramedullary haematopoiesis were compound heterozygotes for IVS 1-6/codon 39. A high frequency of thrombotic events was also recorded among all patients followed at our centre with this genetic profile.
  
  
  CONCLUSIONS
  Among our cohort of thalassaemic polytransfused patients, extramedullary haematopoiesis was not such a rare event. Furthermore, we identified a group of patients, most of whom were compound heterozygotes for IVS 1-6/codon 39, with increased soluble transferrin receptor levels and excessive expansion of erythroid marrow probably responsible for the tendency to develop extramedullary haematopoiesis.
authors.affiliation: Department of Oncohaematology, U.O.S.D. "A. Mastrobuoni" Microcythaemia Centre, "A. Cardarelli" Hospital (AORN), Naples, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Ricchi
authors.affiliation: Department of Oncohaematology, U.O.S.D. "A. Mastrobuoni" Microcythaemia Centre, "A. Cardarelli" Hospital (AORN), Naples, Italy.
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Ammirabile
authors.affiliation: Department of Oncohaematology, U.O.S.D. "A. Mastrobuoni" Microcythaemia Centre, "A. Cardarelli" Hospital (AORN), Naples, Italy.
authors.forename: Anna
authors.initials: A
authors.lastname: Spasiano
authors.affiliation: Department of Oncohaematology, U.O.S.D. "A. Mastrobuoni" Microcythaemia Centre, "A. Cardarelli" Hospital (AORN), Naples, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Costantini
authors.affiliation: Department of Diagnostic Services, U.O.C., Biochemical Clinic, A.O.R.N. dei Colli Hospital, Naples, Italy.
authors.forename: Tiziana
authors.initials: T
authors.lastname: Di Matola
authors.affiliation: Magnetic Resonance Imaging Unit, Fondazione G. Monasterio, CNR-Regione Toscana, Pisa, Italy.
authors.forename: Alessia
authors.initials: A
authors.lastname: Pepe
authors.affiliation: Department of Oncohaematology, U.O.S.D. "A. Mastrobuoni" Microcythaemia Centre, "A. Cardarelli" Hospital (AORN), Naples, Italy.
authors.forename: Patrizia
authors.initials: P
authors.lastname: Cinque
authors.affiliation: Department of Oncohaematology, U.O.S.D. "A. Mastrobuoni" Microcythaemia Centre, "A. Cardarelli" Hospital (AORN), Naples, Italy.
authors.forename: Leonilde
authors.initials: L
authors.lastname: Pagano
authors.affiliation: Department of Oncohaematology, U.O.S.D. "A. Mastrobuoni" Microcythaemia Centre, "A. Cardarelli" Hospital (AORN), Naples, Italy.
authors.forename: Maddalena
authors.initials: M
authors.lastname: Casale
authors.affiliation: Department of Oncohaematology, U.O.S.D. "A. Mastrobuoni" Microcythaemia Centre, "A. Cardarelli" Hospital (AORN), Naples, Italy.
authors.forename: Aldo
authors.initials: A
authors.lastname: Filosa
authors.affiliation: Department of Oncohaematology, U.O.S.D. "A. Mastrobuoni" Microcythaemia Centre, "A. Cardarelli" Hospital (AORN), Naples, Italy.
authors.forename: Luciano
authors.initials: L
authors.lastname: Prossomariti
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D009202:Cardiomyopathies / Q000453:epidemiology / Q000209:etiology; D005260:Female; D005838:Genotype; D006411:Hematopoiesis, Extramedullary; D006454:Hemoglobins / Q000032:analysis; D006579:Heterozygote; D006801:Humans; D007438:Introns / Q000235:genetics; D019190:Iron Overload / Q000453:epidemiology / Q000209:etiology; D007558:Italy; D008297:Male; D008875:Middle Aged; D011990:Receptors, Transferrin / Q000097:blood; D012189:Retrospective Studies; D013156:Splenectomy; D019851:Thrombophilia / Q000209:etiology / Q000235:genetics; D055815:Young Adult; D055544:beta-Globins / Q000235:genetics; D017086:beta-Thalassemia / Q000235:genetics / Q000503:physiopathology* / Q000601:surgery / Q000628:therapy
chemical_list: D006454:Hemoglobins; D011990:Receptors, Transferrin; D055544:beta-Globins