A retrospective study of ocular toxocariasis in Japan: correlation with antibody prevalence and ophthalmological findings of patients with uveitis

To classify the clinical characteristics of ocular toxocariasis in Japan, t he prevalence of antibodies to Toxocara antigens was examined in patients w ith uveitis of unknown aetiology. From 1982 to 1993, serum specimens of 383 cases and intraocular fluid samples of 22 cases were serologically screene d for Toxocara infection with five immunodiagnostic tests. Fifty-five sera and 11 intravitreous fluid samples were estimated to have significantly hig h antibody levels against larval excretory-secretory (ES) antigens of T. ca nis. Eight cases were positive in both serum and vitreous fluid, and three were positive only in the vitreous fluid. Among the 58 antibody positive sa mples, 20 cases were omitted due to a lack of detailed description of ocula r findings. The remaining 38 cases are described in this study. Of these 38 cases, 34 (89%) were older than 20 years of age. Ocular lesions were locat ed in the posterior fundus in 11 cases, in the peripheral fundus in 18 case s, and in both areas in seven cases. Of the eight cases in which papillary oedema or redness was observed, chorioretinal lesions were also present in seven of them. Tractional retinal detachment was present in five cases. The se observations suggest that ocular toxocariasis in Japan has a different c linical profile compared with those in the other countries, and indicate a need for revised classification of ocular toxocariasis.