COGNITIVE, HEMATOPOIETIC AND GASTROINTESTINAL IMPAIRMENTS CAUSED BY VITAMIN B12 DEFICIENCY – PATOGENESIS, TREATMENT AND PATIENT CARE

Many studies have investigated the pathogenetic association of cognitive, hematopoietic, and gastrointestinal impairments with low vitamin B12 concentrations. The aim of our study is to point out the importance of maintaining vitamin B12 concentrations in the body, in order to preserve cognition, but also other vital parameters of the body. For a systematic literature search on studies on the association of cognitive, hematopoietic and gastrointestinal impairments with vitamin B12 deficiency, we used we used the databases: Web of Science, PubMed, Google Scholar. The search keywords included “vitamin B12“, “cognition“, “anemia“ and “gastrointestinal diseases“. Vitamin B12 deficiency can lead to cognitive disorders and dementia in addition to hematological and gastrointestinal symptoms. This can occur due to insufficient intake, inadequate absorption or its reduced utilization. Vitamin B12 is involved in myelin repair, amino acid metabolism, and bone marrow cell production. If there is a vitamin B12 deficiency in the body, symptoms usually first appear in the gastrointestinal tract. Due to the lack of intrinsic factor and the presence of autoantibodies against gastric parietal cells or intrinsic factor, vitamin B12 absorption disorders and pernicious anemia occur. After gastrectomy, but also after removal of the distal ileum or the presence of tumors that interfere with absorption, achlorhydria and pepsin deficiency occur, which causes vitamin B12 deficiency and megaloblastic anemia. Due to the lack of vitamin B12 in the body, significant damage can occur and its compensation through supplementation is necessary. Therefore, it is necessary to determine this deficiency in a timely manner in order to prevent its consequences, which may be irreversible.