CLINICAL MICROBIOTA TESTING, INTERPRETATION PRINCIPLES, AND FUTURE PERSPECTIVES

The human microbiota, recognized as a complex ecosystem with decisive effects on host health and disease processes, has become a significant area of focus in modern medicine. While interest in microbiota-based tests for clinical applications is growing, interpreting these tests still presents considerable challenges. A lack of standardization, inconsistencies between methods, and insufficient evidence regarding clinical utility are among the primary limitations. Methods used in microbiota analysis generally include culture-based approaches, 16S rRNA gene sequencing, shotgun metagenomic analysis, and multiomic integrations. Although each method offers a different perspective, none alone provides a complete picture of the microbiota. Culture-based tests only reveal cultivable microorganisms; while this offers an advantage for assessing viability, its scope is limited because a large proportion of the microbial community cannot be cultured. 16S rRNA sequencing is a practical and widely used method for profiling bacterial communities, but its capacity to differentiate at the species and especially strain level is limited. Shotgun metagenomics provides a much broader range of information regarding genetic content and functional potential, but its widespread clinical adoption is taking time due to both cost and analytical complexity. Multi-omic approaches, which integrate genetic potential with metabolic outputs and real-time microbial activities, offer the most comprehensive overview; however, they are currently mostly used in research due to high technical requirements and interpretation difficulties. The advancement of AIsupported analytical tools, the clarification of biomarkers, and the integration of microbiota-based therapies into clinical protocols will significantly increase the importance of these tests in decision-making processes. However, reaching this point requires the establishment of interna-tional standards, strengthening interdisciplinary collaborations, and the widespread conduct of clinical studies based on robust methodology. In conclusion, the appropriate selection of methods based on the clinical question and the careful interpretation of findings within a biological context are of paramount importance. Considering the complementary aspects of culture-based, molecular, and multiomic approaches, microbiota tests are expected to become a routine component of modern medicine in the near future.