OCULAR TOXOPLASMOSIS IN THE FETUS - IMMUNOHISTOCHEMISTRY ANALYSIS ANDDNA AMPLIFICATION

Purpose: Ocular toxoplasmosis is often the result of a congenital infe ction. However, the earlier stages of the ocular lesions in the fetus have not been well studied. The purpose of the present study is to ana lyze the ocular findings in four aborted fetuses that were infected co ngenitally with Toxoplasma gondii. Methods: Eight eyes from four fetus es of 22 to 27.5 weeks with T. gondii infection were studied by routin e and immunohistochemical techniques. Two of the four were also examin ed by polymerase chain reaction (PCR). Results: In two cases, the resu lts of gross and histopathologic of the eyes were normal; marked retin al necrosis was present in the other two cases. Although no toxoplasmi c cysts were identified by routine histopathologic examination, antige ns of the tachyzoite were detected by immunohistochemistry analysis in the areas of retinal necrosis. In one of the cases with ocular lesion s, the presence of T. gondii was confirmed by PCR. The presence of ocu lar lesions correlated with the severity of pathologic changes in the central nervous system. Large numbers of T cells were observed in the retinal lesions and in the choroid. Conclusion: Retinal necrosis, neov ascularization, and marked chorioretinal inflammations despite the abs ence of bradyzoites are characteristic findings in the fetal eyes infe cted with T. gondii, and infiltrating T lymphocytes play a role in ear ly recognition of the toxoplasma organism.