Histopathological diagnosis of ocular toxoplasmosis in eviscerated eyes

Purpose To present two cases of ocular toxoplasmosis diagnosed by histopathological examination of eviscerated eyes. Observations Ocular toxoplasmosis is primarily a clinical diagnosis, however atypical presentations and limitations in serological and molecular testing make the diagnosis challenging. We report two patients who were infected by the parasite Toxoplasma gondii and underwent evisceration of their blind eye. Histopathological analysis of the intraocular contents in each case demonstrated retinal necrosis located above and below the retinal pigment epithelium (RPE), identification of tachyzoites and bradyzoites, and confirmatory immunohistochemical method for Toxoplasma gondii using monoclonal antibodies. These findings are similar to previously described histopathological criteria in enucleated eyes with ocular toxoplasmosis. Conclusion and importance This is the first report demonstrating histopathological diagnosis of ocular toxoplasmosis using evisceration rather than enucleation in immunocompromised patients. These findings support consideration of evisceration as an alternative to enucleation and highlight three key histopathological features essential for diagnosis.