Object of the research: HIV infection in pregnant. Purpose of the research: To determine structural-functional characteristics of the tissue of the thymus, spleen and mesenterial lymph nodes in fetuses, newborns and infants from HIV-infected mothers based on the results of complex pathomorphological analysis. Methods of research: Macroscopy, organometry, histological, histochemical, immunohistochemical investigation, morphometry, statistical analysis. Practical significance of the obtained findings: The findings of the profound morphological investigation of the thymus, spleen, mesenteric lymph nodes of dead fetuses and infants born from HIV-infected mothers allow to increase the quality of pathological diagnosis. Using these findings clinicians can predict the course of the disease and improve the methods of treatment with the account of the revealed changes in the immune system. It is reasonable to introduce the findings of the research in the teaching process of higher medical schools when preparingpediatricians, specialists in infectious diseases, pathologists, general practitioners. Novelty of the obtained findings: For the first time, the changes of intrauterine thymus, spleen, and mesenterial lymph node development caused by HIV-infection in the mother were revealed. The character of disorders in the morpho-functional activity of the thymus, spleen, mesenterial lymph nodes depending on the time of HIV infection was revealed. It was shown that HIV infection of the mother during pregnancy was realized in disorders of intrauterine development of the thymus, spleen and mesenterial lymph nodes manifesting by atrophy, dysplasia and hyperplasia of lymphoid and epithelial components. Degree of introduction: The findings of the research were introduced to the work of pathology departments of Kharkiv Regional Clinical Hospital For Infectious Diseases, Dnipropetrovsk and Odesa regional pathology bureaux, as well as teaching process of department of general and clinical pathology of faculty of fundamental medicine of Kharkiv National University named after V.Karazin, pathology department of Kharkiv National Medical University, pathology department of Odesa State Medical University. Area of application: pathology, infections in children
