Fifty cases with suspected toxoplasmic ocular lesions were detected from Ophthalmology Department in Benha University Hospital. Samples from serum and aqueous humour were collected and examined by IFAT for detection of anti-Toxoplasma anti bodies, and by single radial immune-diffusion for total IgG estimation.
Eleven cases (22%) showed positive antibody titre in serum and aqueous humour. 3 cases showed positive aqueous humour anti body titre and 6 cases showed positive serum antibody titre. Eight cases (16%) showed aqueous humour antibody coefficient . 8 indicating conclusive proof that the lesion is caused by Toxoplasma organisms.
High positivity rates were recorded in the age group below 20 years (36.3%) than between 20-60 years (25. 6%) and in females (52%) than males (29%).
INTRO TION
Ocular toxoplasmosis is a focal necrotizing retinochoroiditis affecting mainly the posterior pole of the eye. It is divided into congenital and acquired forms. Perkins (2) stated that congenital toxoplasmosis of the eye may be in the form of macular lesions, old scars, general iredouveitis, microphthalmos, convergent or divergent squint, cataract and optic neuritis.
A study by Safar et at. (3) on the preva knce of Toxoplasma antibodies among ocular diseases revealed that the percentage positivity of toxoplasmosis was 36% being specially high as 71.4% in the age group up to 10 years old. Most of those cases were diagnosed as retinochoroiditis.
The reported ocular lesions, which may occur due to acquired infection were, re tinochoroiditis, macular choroiditis, uveitis, optic nerve lesion, interstitial keratitis, ocular muscle paresis and others (2).
Gump and Holden (4) reported a case of acquired toxoplasmosis that presented by diminution of vision.
Witmer (5) stated that, attacks of toxoplasmic retinochoroiditis, do not lead to an increase in serum antibodies, although the level in the aqueous is increased. Demonstration of local produc tion of antibodies in the eye enables the ophthalmologist to make specific etiological diagnosis.
Testing aqueous humour for antibodies against toxoplasmosis and comparing the results with those in serum is a very stringent criteria for diagnosis of ocular toxoplasmosis (1).
This work aims to assess the relation between Toxoplasma antibodies in
E.M.J. Vol.8 No.! Jan. 1991 (1)
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