Steroid-responsive functional B12 deficiency in association with transcobalamin II polymorphism 776C --> G

Eur J Haematol. 2006 Jan;76(1):75-8. doi: 10.1111/j.1600-0609.2005.00563.x.


We present a case of intracellular vitamin B12 deficiency presenting with confusion, subacute combined degeneration of the cord, megaloblastic anaemia and intrinsic factor antibodies in the serum. Diagnosis was delayed by a normal serum B12 level and was confirmed by a grossly elevated serum homocysteine. There was a dramatic response to steroids. The patient was heterozygous for the transcobalamin (TC) II polymorphism 776C --> G. This case demonstrates the importance of functional assessment of intracellular B12 activity (e.g. serum homocysteine) in excluding B12 deficiency, the role of steroids in pernicious anaemia and a possible clinical correlation of a TCII polymorphism.

Publication types

  • Case Reports

MeSH terms

  • Aged
  • Anemia, Megaloblastic / blood
  • Anemia, Megaloblastic / complications
  • Anemia, Megaloblastic / drug therapy
  • Anemia, Megaloblastic / genetics
  • Female
  • Heterozygote
  • Humans
  • Polymorphism, Single Nucleotide*
  • Steroids / administration & dosage
  • Transcobalamins / genetics*
  • Vitamin B 12 Deficiency / blood
  • Vitamin B 12 Deficiency / complications
  • Vitamin B 12 Deficiency / drug therapy
  • Vitamin B 12 Deficiency / genetics*


  • Steroids
  • Transcobalamins