[Ocular toxoplasmosis. Comparison between two biological methods to study aqueous humor]. / Toxoplasmose oculaire. Comparaison de deux méthodes biologiques pour l'étude de l'humeur aqueuse.

To diagnose ocular toxoplasmosis with certainty is often difficult and requires anti Toxoplasma gondii antibodies screening in the aqueous humour. We evaluated the results obtained in 30 controls and 5 patients investigated, using the ELISA and indirect immunofluorescence techniques to determine Desmonts's C coefficient and the sera/aqueous humour densities ratio obtained with ELISA. None of the chorioretinitis-free controls showed a false positive result. Negative serum antibodies levels indicated an absence of ocular toxoplasmosis. The sensitivity of this method depends on several biological parameters, notably the extent of ocular inflammation. Evaluating the C coefficient by the ELISA technique increases this sensitivity.