title: Vitamin B12 deficiency - A 21st century perspective .
abstract: Vitamin B12 deficiency is a common condition which can present with non-specific clinical features, and in severe cases with neurological or haematological abnormalities. Although classically caused by pernicious anaemia, this condition now accounts for a minority of cases and vitamin B12 deficiency occurs most often due to food-bound cobalamin malabsorption. Since missing the diagnosis can result in potentially severe complications, including degeneration of the spinal cord and pancytopaenia, vitamin B12 deficiency must be diagnosed early and managed appropriately. Intramuscular injections have been the mainstay of treatment, but oral replacement therapy can be effective in many cases. There is accumulating evidence that high vitamin B12 levels (values varied from 350-1,200 pmol/l) are associated with haematological and hepatic disorders, in particular with malignancy. This review focuses on the developments in the clinical features and management of vitamin B12 deficiency over the last decade.
authors.affiliation: School of Medicine, University of Manchester, Manchester, UK;
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Shipton
authors.affiliation: Department of Haematology, Manchester Royal Infirmary, Manchester, UK jecko.thachil@cmft.nhs.uk.
authors.forename: Jecko
authors.initials: J
authors.lastname: Thachil
mesh_terms: D006801:Humans; D014805:Vitamin B 12 / Q000008:administration & dosage / Q000097:blood / Q000502:physiology; D014806:Vitamin B 12 Deficiency / Q000175:diagnosis* / Q000628:therapy*
chemical_list: D014805:Vitamin B 12
keywords: B12; cobalamin; deficiency; vitamin
references.citation: QJM. 2013 Jun;106(6):505-15
references.pmid: 23447660
references.citation: Curr Opin Gastroenterol. 2012 Mar;28(2):151-8
references.pmid: 22241075
references.citation: BMC Public Health. 2012 May 31;12:394
references.pmid: 22650964
references.citation: N Engl J Med. 1997 Nov 13;337(20):1441-8
references.pmid: 9358143
references.citation: Cardiology. 2007;107(1):57-62
references.pmid: 16763373
references.citation: Nat Rev Gastroenterol Hepatol. 2012 May 01;9(6):345-54
references.pmid: 22547309
references.citation: Fam Pract. 2006 Jun;23(3):279-85
references.pmid: 16585128
references.citation: JAMA. 2013 Dec 11;310(22):2435-42
references.pmid: 24327038
references.citation: JAMA. 2009 Nov 18;302(19):2119-26
references.pmid: 19920236
references.citation: J Nutr Health Aging. 2011 Mar;15(3):227-31
references.pmid: 21369672
references.citation: Clin Chem Lab Med. 2013 Mar 1;51(3):489-96
references.pmid: 23241600
references.citation: PLoS One. 2014 Jun 24;9(6):e100379
references.pmid: 24959880
references.citation: Am J Clin Nutr. 2003 Jul;78(1):3-6
references.pmid: 12816765
references.citation: Biochimie. 2013 May;95(5):1066-76
references.pmid: 23228515
references.citation: J Bone Miner Res. 2005 Jan;20(1):152-8
references.pmid: 15619681
references.citation: BMJ. 2010 May 20;340:c2181
references.pmid: 20488910
references.citation: Curr Ther Res Clin Exp. 2005 Jan;66(1):13-22
references.pmid: 24672108
references.citation: Blood. 1998 Aug 15;92(4):1191-8
references.pmid: 9694707
references.citation: Br J Haematol. 2014 Aug;166(4):496-513
references.pmid: 24942828
references.citation: J Neuropsychiatry Clin Neurosci. 2012 Winter;24(1):5-15
references.pmid: 22450609
references.citation: Blood. 2008 Sep 15;112(6):2214-21
references.pmid: 18606874
references.citation: Am J Clin Nutr. 2009 Feb;89(2):693S-6S
references.pmid: 19116323
references.citation: Clin Ther. 2011 Mar;33(3):358-371.e2
references.pmid: 21600388
references.citation: N Engl J Med. 2013 Jan 10;368(2):149-60
references.pmid: 23301732
references.citation: QJM. 2009 Jan;102(1):17-28
references.pmid: 18990719
references.citation: Am J Med. 2001 Aug;111(2):126-9
references.pmid: 11498066
references.citation: CMAJ. 2004 Aug 3;171(3):251-9
references.pmid: 15289425
references.citation: Clin Nutr. 2012 Feb;31(1):53-9
references.pmid: 21899932
references.citation: J Am Geriatr Soc. 2010 Mar;58(3):523-6
references.pmid: 20158555