AIMS--This study was set up to determine the long term ocular and systemic sequelae in patients with severe congenital toxoplasmosis. METHODS--Cross sectional and retrospective study of 17 patients with severe congenital toxoplasmosis. RESULTS--In addition to chorioretinitis (100%), the most common abnormal ocular features were optic nerve atrophy (83%), visual acuity of less than 0.1 (85%), strabismus, and microphthalmos. In 50% of cases we observed iridic abnormalities and about 40% developed a cataract. Overt endocrinological disease, diagnosed in five of 15 patients, included panhypopituitarism (n = 2), gonadal failure with dwarfism (n = 1), precocious puberty with dwarfism and thyroid deficiency (n = 1), and diabetes mellitus and thyroid deficiency (n = 1). The observed endocrinological involvement was associated in all cases with obstructive hydrocephalus with a dilated third ventricle and optic nerve atrophy. CONCLUSION--The recognition of long term ocular, neurological, and endocrinological sequelae of congenital toxoplasmosis is important for medical management of these severely handicapped patients.