At the age of 1 year congenital toxoplasmosis presents a wide spectrum of clinical signs ranging from patent neurological abnormalities to sub clinical infection. At this age treatment is usually discontinued as only cyst stage of parasites are present on which the currently used drugs are inefficient.
Patients with severe lesion, mainly hydrocephalus associated or not to visual impairment usually born from women who were not screened during pregnancy have to be placed in institution or have to be enrolled in special care programs.
Children treated ante and perinatally displayed a totally different presentation. In this setting gross abnormalities are very rare. In a cohort of 480 congenitally infected newborns we observed 5 hydrocephalus. Retinochoroiditis were observed in 8 cases. Ocular lesions are generally diagnosed later in life either because lesions are peripheral or because they occurred later, even after the age of 10. Occurrences or relapses are usually unpredictable but age (6 and 11 years) or pregnancy appear to be periods of risk.
In such clinical settings congenital toxoplasmosis should be considered as a chronic ophthalmologic disease. Weather these patients should be regularly followed is debatable but for counselling pregnant women who seek for information about the long term outcome in their infants such systematic follow up is the only way for providing unbiased information. In a cohort of congenitally infected adults yearly checked since childhood, visual function and quality of life scored well and majority of participant endorsed long term ophthalmologic follow up.