[Pathomorphology of experimental ornithosis pneumonia]

Model experiments in white mice reproduced chronic ornithosis pneumonia morphological features of which included early outgrowth of connective tissue cells of the type of carnification, considerable accumulation of tropoglycogen, and disturbed process of collagen fibers formation at a minimal number of leukocytes. Such foci occur in the lungs very early, before the onset of the clinical signs of the disease which appears to be a typical feature of ornithosis pneumonia and may explain causes and mechanisms of frequent occurrence of chronic forms of this disease. In cases of significant multiplication of the ornithosis agent there is mass migration of leukocytes into the focus of lesion followed by the development of acute inflammation. Being an obligatory intracellular parasite, the ornithosis agent affects both large and small alveolar cells. Multiplying by binary division, it stays free in the cytoplasm without forming a common vacuole. Ultrastructurally typical various forms of the ornithosis agent reflecting the stages of its complicated life cycle have been detected.