Ultrastructural characteristics of leishmania (L.)tropica (Wright, 1903) and cell-parasite relationships in cutaneous leishmaniasis. Light and electron microscopic study

A light and electron microscopic study of skin biopsies taken from 9 patients with ulcerative leishmaniasis of both sexes aged from 14 to 26 years in the territory of the Republic of Azerbaijan was carried out. Based on clinical, morphological and electron microscopic parameters, all patients were diagnosed with ulcerative cutaneous anthroponotic leishmaniasis (Leishmania (L.) tropica). Stained and unstained ultrathin (50-70 nm) sections were viewed and photographed using a JEM-1400 transmission electron microscope at an accelerating voltage of 80-120 kV. Analysis of data from light and electron microscopic studies at the ultrastructural level made it possible to describe the structure and identify the morphometric parameters of the amastigote form of the intracellular parasite. Besides, it was found that the distance between the plasmalemmas of the parasitophorous vacuoles and the parasite L. (L.) tropica is only 1 nm. This facilitates the passage of the necessary nutrients for the survival of this parasite. One of the important factors in the chronic course and relapse of leishmaniasis caused by L.(L.) tropica is the penetration of the amastigote stage into the cytoplasm along with macrophages, and also into fibroblasts with low phagocytic activity. Pathological changes (deformed nucleus, damage to plasmalemma, focal destruction of the cytoplasm structures, vacuolization, etc.) in the parasite L. (L.) tropica, localized in macrophages, were identified and described.