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Published: 03-06-2023

Consensus of the Brazilian Association of Nutrology on diagnosis, prophylaxis, and treatment of vitamin B12 deficiency

UFSCAR - Federal University of Sao Carlos, department of medicine, Sao Carlos, Sao Paulo, Brazil / ABRAN - Associação Brasileira de Nutrologia/Brazilian Association of Nutrology, Catanduva, Sao Paulo, Brazil
UFBA - Federal University of Bahia, Bahia, Brazil / ABRAN - Associação Brasileira de Nutrologia/Brazilian Association of Nutrology, Catanduva, Sao Paulo, Brazil
CESMAC - University center (Center for Higher Education of Maceió), Maceió, Alagoas, Brazil / ABRAN - Associação Brasileira de Nutrologia/Brazilian Association of Nutrology, Catanduva, Sao Paulo, Brazil
UNIFESP - Hematology and Hemotherapy at Paulista School of Medicine, São Paulo, Brazil / ABRAN - Associação Brasileira de Nutrologia/Brazilian Association of Nutrology, Catanduva, Sao Paulo, Brazil
FACERES – Faculty of Medicine of Sao Jose do Rio Preto, Sao Paulo, Brazil / ABRAN - Associação Brasileira de Nutrologia/Brazilian Association of Nutrology, Catanduva, Sao Paulo, Brazil
ABRAN - Associação Brasileira de Nutrologia/Brazilian Association of Nutrology, Catanduva, Sao Paulo, Brazil
ABRAN - Associação Brasileira de Nutrologia/Brazilian Association of Nutrology, Catanduva, Sao Paulo, Brazil / FAMECA/UNIFIPA- Faculty of Medicine of Catanduva / Padre Albino University Center, Medicine Course, Catanduva, São Paulo, Brazil
Vitamin B12 Deficiency Treatments Routes of administration


Introduction: Vitamin B12 deficiency is quite prevalent in all age groups and all regions of the country, however, there is a need for standardization of clinical management recommendations. Objective: It was to achieve a consensus on the diagnosis, prophylaxis, and treatment of vitamin B12 deficiency. Methods: An integrative review of the scientific literature was carried out in Scopus, PubMed, Science Direct, Scielo, and Google Scholar databases and on governmental and regulatory websites. Results: According to the literary search carried out by the authors of this study, 84 scientific works were selected. Based on these findings, in the timeline from 1999 to 2022, randomized controlled clinical studies represented the majority, and prospective and retrospective studies with significant sample sizes were elucidated in this consensus on the vitamin B12 administration for all patient populations. The basis of this scientific evidence was determined by appropriate clinical trials, with additional endpoints including patient clinical symptoms and biochemical parameters in addition to serum and marginal B12 level. Conclusions: Based on the scientific literature, the recommendations of the Brazilian Association of Nutrology for diagnosis, prophylaxis, and treatment of vitamin B12 deficiency were presented.


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How to Cite

Nogueira-de-Almeida, C. A., Fernandes, S. L., Soriano, E. de A., Lourenço, D. M., Zotarelli Filho, I. J., Iucif Junior, N., & Ribas Filho, D. (2023). Consensus of the Brazilian Association of Nutrology on diagnosis, prophylaxis, and treatment of vitamin B12 deficiency. International Journal of Nutrology, 16(1).