DISORDERS OF VITAMIN B12 METABOLISM IN PATIENTS WITH GASTRITIS AND OTHER INFLAMMATORY GASTRIC DISEASES

This article provides a comprehensive and structured review of current scientific evidence concerning disorders of vitamin B₁₂ metabolism in patients with gastritis and other inflammatory diseases of the stomach.Particular emphasis is placed on the pathogenetic mechanisms through which chronic inflammatory changes of the gastric mucosa-especially atrophic and autoimmune gastritis-lead to impaired secretion of hydrochloric acid and intrinsic factor, both of which are essential for normal cobalamin absorption.Special attention is devoted to the role of Helicobacter pylori infection, which promotes chronic inflammation, mucosal atrophy, and functional deterioration of the gastric glands, thereby contributing to the development and progression of vitamin B₁₂ deficiency.The review analyzes the key pathophysiological pathways underlying cobalamin deficiency and discusses its diverse clinical manifestations, including megaloblastic anemia, peripheral neuropathy, cognitive decline, and neuropsychiatric disturbances.It is highlighted that neurological and cognitive symptoms may occur independently of hematological changes, which complicates early diagnosis and increases the risk of irreversible complications.Contemporary diagnostic approaches to assessing disturbances of vitamin B₁₂ metabolism are examined, with a focus on laboratory markers such as serum cobalamin, homocysteine, and methylmalonic acid levels, as well as the diagnostic value of endoscopic and histological evaluation of the gastric mucosa in identifying atrophic and autoimmune changes.The clinical importance of early detection and timely correction of vitamin B₁₂ deficiency in patients with inflammatory gastric diseases is emphasized.The review underscores that effective management requires not only appropriate cobalamin replacement therapy but also etiological treatment of the underlying gastric pathology.An integrated diagnostic and therapeutic approach can improve clinical outcomes, prevent long-term neurological sequelae, and enhance patients' quality of life.Overall, the analyzed data support the need for further research aimed at optimizing diagnostic algorithms, screening strategies, and personalized treatment approaches for managing vitamin B₁₂ deficiency in this patient population.