Development of adverse sequelae in children born with subclinical congenital Toxoplasma infection.

Most infants born with congenital Toxoplasma infection are asymptomatic in the newborn period, and therefore their infection is not recognized. We performed follow-up evaluations on 24 such children. The mean age of these children at least examination was 8.5 years. In group I (13 children), the diagnosis was made prospectively. In group II (11 children), no symptoms or signs were noted in the newborn period and the diagnosis was made only after the first sign developed. Eighty-five percent of the children in group I and all of the children in group II have developed chorioretinitis. In group I, three children (23%) have unilateral blindness; in group II, three children (27%) and five children (45%) have unilateral and bilateral blindness, respectively. One child (8%) in group I and two children (18%) in group II developed severe, permanent neurologic sequelae after they initially presented with eye disease. Two of the children in each group are now retarded (IQ score range, 36 to 62). Six of the children in group I who were tested sequentially have had lower IQ scores (mean change from 97 to 74) on repeat tests performed an average of 5.5 years later. Less severe neurologic, intellectual, and audiologic deficits were observed in other children in each group. Treatment of some children may have had a beneficial effect on their outcome.