Pathogenic characteristics of intracellular infection in chlamydiosis

Abstract

This review analyzes scientific data and systematized information regarding microbiological aspects and pathogenesis of chlamydia infection. Chlamydia are obligate intracellular microorganisms that are sensitive to any human cells where energy parasitism is possible: various types of epithelium, fibrocytes, histiocytes, glial and muscle cells, squamous epithelium of the meninges and eyeball, neurons, monocytes, macrophages. Structure, chemical composition and enzymatic activity of Chlamydia closely resemble those in Gram-negative bacteria, as they retain their morphological identity throughout the life cycle, possess cell wall, ribosomes, DNA, RNA, biochemical elements of glycolysis, tissue respiration, peptose production being sensitive to some broad-spectrum antibiotics, and are able to vegetative form division. In recent decades, the pathogenesis and clinical symptoms of chlamydial lesions in the urogenital tract, nervous, cardiovascular, musculoskeletal and bronchopulmonary systems have been actively studied, and new approaches and treatment schemes for chlamydia-infected patients are still developing. Over many decades, Chlamydia infection has been an important and urgent problem, not only due to its high prevalence, but also because of high rate of complications negatively affecting populational health and related demographic parameters. Chlamydia causes multiple diseases resulting in chronization of inflammatory process in all human organs and systems, and affects reproduction of population. Mandatory statistical recording of chlamydiosis cases introduced as early as in 1994 in the Russian Federation does not reflect the actual incidence rate. A rise in number of inflammatory diseases of the upper respiratory tract caused by Chlamydia undoubtedly increases its etiological importance, but data regarding etiopathogenetic role of Chlamydia in ENT pathology are ambiguous and contradictory. Available publications describe a large range of variation in rate of detected Chlamydia due to poor awareness of doctors about the microbiological properties of chlamydia, pathogenetic and clinical features of clinical signs of this infection, and lack of common and clear understanding on the algorithms for identifying and treating chlamydiosis. Since the majority of chlamydia-associated nosological forms are asymptomatic, knowing pathogenetic features of related will allow to prevent the spread of the infection and reduce subsequent socio-economic consequences.