[The clinical and morphological features of Chlamydia pneumoniae-induced chorioretinitis in an experiment]

The clinical and pathomorphological features of vitreous retinochorioidal complex lesion with the pathogen Chlamydia pneumoniae were studied. Three rabbits (6 eyes) were infected with Ch. pneumoniae strain TWAR by instillation, subconjunctivally and 2 eyes were infected by intravitreally. Contamination was controlled by direct immunofluorescence and cultivation (conjunctival scrapes, venous blood). A postmortem study was conducted 128 days later, by employing an immunohistochemical analysis. On days 7-14, all cases showed the signs of a uveal reaction; 4 cases developed chorioretinitis. In 2 cases, the process ran as endophthalmitis with minimal clinical manifestations. The rate of the process was decreased by days 40-50. On the postmortem study, all the cases displayed lymphocytic-macrophageal infiltration in the vitreous body and retina in the presence of retinal focal dystrophic changes. An immunohistochemical study revealed the pathogen in different retinal layers (both inside and outside the chorioretinal foci) in all 6 cases and in the preretinal layers of the vitreous body in 5 cases. The pathogen Ch. pneumoniae is rather highly tropic to the structures of the visual organ and it is able to induce chronic lesion of the structures of the posterior portion of the eye portion with varying clinical manifestations. Dystrophic changes in infected tissues, the vitreous body and chorioretinal complex in particular, are a result of a chronic inflammatory process.