Diagnosis & Management of Vitamin B12 Deficiency in Primary Care – Are we following the guidelines?

  • Timothy Shao Ern Tan Manchester Medical School, The University of Manchester
  • Pauline Harris West Gorton Medical Centre, Manchester, United Kingdom
Keywords: Vitamin B12 deficiency, pernicious anaemia, primary care, cyanocobalamin, hydroxocobalamin


Background: Vitamin B12 deficiency is common in primary care but its treatment practices vary across centres. One important cause of B12 deficiency is pernicious anaemia (identified by intrinsic factor antibodies), which is a risk factor for developing gastric carcinoma, and should be excluded. Additionally, recent evidence has suggested that some patients have been continued on B12 injections with no clear clinical indication. Recently,
guidelines were produced to improve the investigation and management of B12 deficiency. Hence, this audit studied the investigation and management of B12 deficiency and adherence to clinical guidelines in a general practice (GP) in north-west England.

Aim: To evaluate the appropriate diagnosis and management of vitamin B12 deficiency in our primary care centre against recognized standards.

Methods: Clinical data of patients currently on oral cyanocobalamin and/or intramuscular hydroxocobalamin injections over a 1-year period were audited.

Results: Thirty-eight patients (66% females, 34% males) receiving treatment for B12 deficiency were identified. Of these, 55% (21/38) had intrinsic factor antibodies checked and 52% (13/25) were managed according to the guidelines. 100% (8/8) of patients with dietary B12 deficiency (non-vegans) and 75% (3/4) of B12-deficient patients on long-term metformin have had follow-up serum B12 monitoring.

Discussion: There is a need to improve the investigation for B12 deficiency, adherence to clinical guidelines, and documentation of patients’ diagnoses, treatment plans, dietary statuses, and required monitoring. We anticipate that adhering to guidelines when appropriate, with clear documentation, will improve the diagnosis and management of vitamin B12 deficiency so that safe prescribing and potential cost savings can be achieved.


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How to Cite
Tan, T., & Harris, P. (2015). Diagnosis & Management of Vitamin B12 Deficiency in Primary Care – Are we following the guidelines?. Res Medica, 23(1), 73-81. https://doi.org/10.2218/resmedica.v23i1.765