[Ocular toxoplasmosis. Utilization of immunohistochemical reaction for diagnosis]

The diagnosis of ocular toxoplasmosis is based primarily on clinical presentation and laboratory tests described else where. Eventually, unusual clinical presentation, as well unusual pathologic findings occur, mainly in immunosuppressed individuals. The authors report a case of a female patient from Paraná with a progressive ocular disease, for at least three years, without definite diagnosis. After an exhaustive clinical and laboratory investigation, as well empiric medical treatment, without success, it was decided to enucleate the atrofic organ and to proceed to a histologic examination. It revealed a cronic and inspecific inflammatory process without any specific agent. However the immunohistochemical technique was able to detect Toxoplasma gondii antigens in the ocular tissue. This technique provides an alternative method for the diagnosis of unusual forms of toxoplasmosis.