Immunoblotting and enzyme linked-immunosorbent assay for diagnosis of ocular toxoplasmosis

Abstract EN

Ocular toxoplasmosis is an important cause of blindness and visual handicap in young people, the clinical diagnosis can be suggestive but not conclusive.

Therefore.

It must be supplemented with laboratory serological tests that might, support or exclude this diagnosis.

In the present work diagnosis of ocular toxoplasmosis was based on the clinical picture and the serological, lest results of enzyme linked-immunosorbent assay (IGM-ELISA) & (IgG- ELISA) and Western blotting of Toxoplasma antigens against sera from ocular patients in the acute and chronic phases of the disease Fourty five cases of suspected ocular toxoplasmosis and five control samples were examined clinically and serologically.

The clinical diagnosis was based on the manifestation of characteristic biomicroscopic features where a white and irregular inflammatory focus is detected frequently in association with an old scar, Fundus examination revealed 5 cases in the acute phase.

27 cases in the chronic phase and 13 atypicat cases Sera were collected to be tested serologically by ELISA and Western blot technique where it was found that the diagnosis was confirmed for 82.3% (37 out of 45 cases) by ELISA ; this rate rose to 88.9% (40 out of 45 cases) by Western blot technique addding better results.

All control sera were negative by ELISA and Western blot.

Toxoploasma gondii cyst antigen was prepared, characterized by SDS-PAGE and recognized by antibodies in serum samples from patients presenting with ocular toxoplasmosis by means of Western bolt technique.

Antigenic hands, 22, 23.

21, 25.

27, 66 and 67 KDa could be characterized as antigenic markers for acute ocular totopiasnmm and 34, 35.

36, 37.

38, 39.

40, 43.

66 and 67 Kda as antigenic markers for chronic ocular toxoplasmosis In the present work immunblotting assay with sensitivity 100% and specificity 62.5% was proved to be an excellent test for diagnosis of ocular toxoplasmosis.

The present work is the first clinico-iminunoiogical study of ocular toxoplasmosis in Assiut University Hospital and the - first work in which immunoblot is applied for diagnosis of ocular toxoplasmosis in Upper –Egypt .