DIAMINE OXIDASE DEFICIENCY AND HISTAMINE INTOLERANCE: CURRENT APPROACHES TO DIAGNOSIS AND DAOPRIM THERAPY

This review summarizes current evidence regarding the clinical and pathogenetic aspects of diamine oxidase (DAO) deficiency, histamine intolerance, contemporary diagnostic approaches, and pathogenetic treatment strate­gies. Histamine intolerance is characterized by impaired degradation of histamine due to reduced DAO activity, leading to the accumulation of histamine and the development of gastrointestinal, dermatological, neurological, res­piratory, and cardiovascular manifestations that often mimic IgE-mediated allergic diseases. A comprehensive analysis of publications indexed in PubMed, Scopus, and Web of Science was performed to evaluate the physiological role of DAO, the contribution of AOC1 gene polymorphisms, intestinal microbiota alterations, clinical phenotypes, and cur­rent diagnostic algorithms. Particular attention was paid to oral exogenous DAO supplementation, including Daoprim, as a promising pathogenetic therapeutic approach. Available evidence suggests that exogenous DAO may reduce symptom severity, improve quality of life, and enhance dietary tolerance in selected patients. However, the current evidence is limited by heterogeneous study designs and relatively small sample sizes. Therefore, large multicenter randomized controlled trials are required to establish standardized diagnostic criteria and to determine the long-term efficacy and safety of DAO replacement therapy in patients with histamine intolerance.