This article provides a scientific analysis of the causative agents of actinomycosis and the diagnostic approaches to the diseases they cause, as well as the clinical and practical significance of atypical (nontuberculous) mycobacteria. The study examines the microbiological characteristics, pathogenesis, and clinical forms of bacteria belonging to the genus Actinomyces, along with the distribution, pathogenicity, and mechanisms of infection caused by nontuberculous mycobacteria. Modern diagnostic methods, including microbiological, histological, and molecular-biological techniques, are evaluated in terms of their effectiveness. The findings highlight the importance of differential diagnosis due to the clinical similarity of these infections to other diseases. The study also emphasizes the necessity of early diagnosis, appropriate treatment strategies, and a comprehensive clinical approach in medical practice.

Actinomycosis, Actinomyces, atypical mycobacteria, nontuberculous mycobacteria, diagnosis, differential diagnosis, granulomatous inflammation, infectious diseases.

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