Pathogenetic features of the macrotypes of chronic endometritis

Aim. To expand the understanding of the pathogenesis of chronic endometritis based on the study of reception and markers of cell proliferation/apoptosis in its various macrotypes depending on the nature of microbial colonization.

Methods. We prospectively examined a group of 345 women with early reproductive losses (history of missed miscarriage, spontaneous abortion, artificial abortion, in vitro fertilisation failures during up to 6 months after intrauterine intervention), who had histologically verified chronic endometritis. A microbiological study of cervical discharge, aspirate from the uterus, identification of the pathogens with PCR, hysteroscopic and pathomorphological study of the endometrium (paypel biopsy) were performed. Identification of hysteroscopic hyperplastic, hypoplastic and mixed macrotypes was carried out on the basis of groups of features characterizing the thickness, color and the structure of the mucous membrane, intensity of vascular pattern in the presence of chronic inflammatory process. Immunohistochemistry of endometrium was performed to determine endometrial receptors for estrogen, progesterone («Dako», Denmark), proliferative activity of endometrial epithelial cells; the intensity of the expression of Ki-67 marker, that marks the cell nucleus at G1-, G2- and S-phase of the mitotic cycle, was taken into account. Apoptosis activity in endometrial biopsies was evaluated on the basis of expression of CPP32 proteins.

Results. Structural and functional disintegration of the endometrium in chronic endometritis is presented as disorders of strictly determined submicroscopic features of the cellular elements of the glandular epithelium and stroma of the endometrium, however, each of the macrotypes has its own characteristic disturbances of homeostasis and homeokinesis of endometrial tissue.

Conclusions. Further study of the markers of signaling pathways regulating proliferative cascades at the endometrial level matched with endometrial response to the invasion of a pathogen and morphological transformations will allow optimizing the diagnosis and treatment of chronic endometritis and restoration of reproductive potential after reproductive losses.