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What causes mycoplasmosis?
Last reviewed: 04.07.2025
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Causes of mycoplasmosis
Mycoplasmas belong to an independent class of microorganisms - more than 40 species of this family are known. Most of them cause diseases in animals and birds. In humans, 6 types of mycoplasmas are mainly found: M. pneumoniae, M. hominis, M. orale, M. salivarium, M. fermentans and T-mycoplasmas. M. pneumoniae is considered pathogenic, M. hominis and the T-group of mycoplasmas are considered opportunistic. The remaining species are known as commensals. Mycoplasmas can cause damage to the respiratory organs, heart, joints, central nervous system and genitourinary system. Of all the mycoplasmas, M. pneumoniae has been studied the most - it is the causative agent of acute respiratory infections, focal pneumonia, bronchitis, bronchiolitis, croup, polyarthritis, meningitis, etc.
Pathogenesis of mycoplasmosis
The entry points for infection are the mucous membranes of the trachea and bronchi. Mycoplasmas, attaching to the epithelial cells of the respiratory tract, destroy the septa between the epithelial cells and disorganize the tissue architecture. New sections of the bronchial tree and, finally, alveolocytes, in the cytoplasm of which microcolonies of M. pneumoniae are present, are gradually involved in the process. Phenomena of interstitial pneumonia with thickening of the interalveolar septa and possible development of bronchopneumonia occur. In severe cases, hematogenous dissemination is possible with the introduction of mycoplasmas from the sites of primary localization to the liver, central nervous system, kidneys and other organs with the development of a clinical picture of hepatitis, meningitis, nephritis. Secondary bacterial infection is of great importance in the occurrence of bronchopulmonary lesions.