title: Non-transferrin-bound serum iron (NTBI) in megaloblastic anemia: effect of vitamin B(12) treatment.
abstract: BACKGROUND
  The abnormalities in iron metabolism associated with megaloblastic anemia are rapidly reversed by B(12) therapy in pernicious anemia (PA). Although non-tranferrin-bound plasma iron (NTBI) was previously shown to be associated with severe iron overload, its origin is unknown.
  
  
  RESULTS
  Four patients with PA were studied before and after B(12) treatment. NTBI was measured by a fluorescence-based one-step assay. All patients had very high transferrin saturation, NTBI values ranging from 1.1 to 2.6 micromol/l and normal serum ferritins. B(12) treatment resulted in the disappearance of NTBI and normalization of transferrin saturation within 22-42 h.
  
  
  CONCLUSIONS
  The prompt disappearance of NTBI following B(12) therapy implicates catabolic iron derived from ineffective erythropoiesis as the major source of NTBI in untreated PA and possibly in thalassemia major and sideroblastic anemia. Our findings offer further insight into the pathogenesis of NTBI in diseases associated with abnormal erythropoiesis.
authors.affiliation: Department of Medicine E, Petah-Tikva and Sackler Faculty of Medicine, Rabin Medical Center, Belinson Campus, Tel Aviv University, Israel.
authors.forename: Anath
authors.initials: A
authors.lastname: Gafter-Gvili
authors.forename: Miron
authors.initials: M
authors.lastname: Prokocimer
authors.forename: William
authors.initials: W
authors.lastname: Breuer
authors.forename: Ioav Zeev
authors.initials: IZ
authors.lastname: Cabantchik
authors.forename: Chaim
authors.initials: C
authors.lastname: Hershko
mesh_terms: D000328:Adult; D000368:Aged; D000749:Anemia, Megaloblastic / Q000097:blood* / Q000188:drug therapy / Q000209:etiology*; D004920:Erythropoiesis; D005260:Female; D005293:Ferritins / Q000097:blood; D006801:Humans; D007501:Iron / Q000097:blood* / Q000378:metabolism; D019190:Iron Overload / Q000209:etiology; D008297:Male; D008875:Middle Aged; D014168:Transferrin / Q000032:analysis; D014805:Vitamin B 12 / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D014168:Transferrin; D005293:Ferritins; D007501:Iron; D014805:Vitamin B 12