Longitudinal study of new eye lesions in treated congenital toxoplasmosis.

OBJECTIVE: To determine the incidence of new chorioretinal lesions in patients with congenital toxoplasmosis who were treated throughout their first year of life. DESIGN: Prospective longitudinal observation of a cohort. PARTICIPANTS: One hundred thirty-two children were studied as part of the longitudinal observation. METHODS: One hundred thirty-two children were treated during their first year of life with pyrimethamine, sulfadiazine, and leucovorin. They had eye examinations at prespecified intervals. MAIN OUTCOME MEASURES: New chorioretinal lesions on fundus examination and fundus photographs. RESULTS: The mean age (+/- standard deviation) is 10.8+/-5.1 years (range, 0.2-23). One hundred eight children have been evaluated for new chorioretinal lesions. Thirty-four (31%; 95% confidence interval, 23%-41%) of 108 children developed at least one chorioretinal lesion that was previously undetected. These occurred at varying times during their follow-up course. Fifteen children (14%) developed new central lesions, and 27 (25%) had newly detected lesions peripherally. Ten (9%) had more than one occurrence of new lesions developing, and 13 (12%) had new lesions in both eyes. Of those who developed new lesions, 14 children (41%) did so at age 10 or later. CONCLUSION: New central chorioretinal lesions are uncommon in children with congenital toxoplasmosis who are treated during their first year of life. This finding contrasts markedly with earlier reports in the literature for untreated children or those treated for only 1 month near birth, in whom new lesions were much more prevalent (>/=82%). Our observation that 14 (41%) of the 34 children with new chorioretinal lesions had occurrences when they were 10 years or older indicates that long-term follow-up into the second decade of life is important in assessing the efficacy of treating toxoplasmosis during infancy.

Longitudinal study of new eye lesions in children with toxoplasmosis who were not treated during the first year of life.

PURPOSE: To determine the incidence of new chorioretinal lesions in children with toxoplasmosis diagnosed after, and therefore not treated during, their first year. DESIGN: Prospective longitudinal cohort study. METHODS: Thirty-eight children were evaluated in Chicago between 1981 and 2005 for new chorioretinal lesions. Thirty-eight children and mothers had serum IgG antibody to Toxoplasma gondii. RESULTS: Twenty-eight of 38 children had one of the following: diagnosis with serum antibody to T. gondii indicative of chronic infection at age 24 months, central nervous system calcifications, hydrocephalus, illness compatible with congenital toxoplasmosis perinatally but not diagnosed at that time. Twenty-five returned for follow-up during 1981 to 2005. Their mean (range) age at last exam was 10.9 +/- 5.7 (range, 3.5 to 27.2) years and mean follow-up was 5.7 +/- 2.9 years. Eighteen (72%) children developed at least one new lesion. Thirteen (52%) had new central lesions, 11 (44%) had new peripheral lesions, and six (24%) had both. Thirteen (52%) had new lesions diagnosed at age > or =10 years. New lesions were found at more than one visit in four (22%), and bilateral new lesions developed in seven (39%) of 18 children who developed new lesions. Of 10 additional children with eye findings and serologic tests indicative of chronic infection, six returned for follow-up, four (67%) developing new lesions at > or =10 years of age. CONCLUSIONS: More than 70% developed new chorioretinal lesions. New lesions were commonly diagnosed after the first decade of life.

Cataracts in congenital toxoplasmosis.

PURPOSE: To determine the incidence and natural history of cataracts in children with congenital toxoplasmosis. METHODS: Children referred to the National Collaborative Chicago-based Congenital Toxoplasmosis Study (NCCCTS) between 1981 and 2005 were examined by ophthalmologists at predetermined times according to a specific protocol. The clinical course and treatment of patients who developed cataracts were reviewed. RESULTS: In the first year of life, 134 of 173 children examined were treated with pyrimethamine, sulfadiazine, and leukovorin, while the remaining 39 were not treated. Cataracts occurred in 27 eyes of 20 patients (11.6%, 95% confidence interval [7.2%, 17.3%]). Fourteen cataracts were present at birth and 13 developed postnatally. Locations of the cataracts included anterior polar (three eyes), anterior subcapsular (six eyes), nuclear (five eyes), posterior subcapsular (seven eyes), and unknown (six eyes). Thirteen cataracts were partial, nine total, and five with unknown complexity. Twelve cataracts remained stable, 12 progressed, and progression was not known for 3. Five of 27 eyes had cataract surgery, with 2 of these developing glaucoma. Sixteen eyes of 11 patients had retinal detachment and cataract. All eyes with cataracts had additional ocular lesions. CONCLUSIONS: In the NCCCTS cohort, 11.6% of patients were diagnosed with cataracts. There was considerable variability in the presentation, morphology, and progression of the cataracts. Associated intraocular pathology was an important cause of morbidity.

Impact of visual impairment on measures of cognitive function for children with congenital toxoplasmosis: implications for compensatory intervention strategies.

OBJECTIVES: The purpose of this work was to determine whether visual impairment caused by toxoplasmic chorioretinitis is associated with impaired performance of specific tasks on standardized tests of cognitive function. If so, then we worked to determine whether there are patterns in these difficulties that provide a logical basis for development of measures of cognitive function independent of visual impairment and compensatory intervention strategies to facilitate learning for such children. METHODS: Sixty-four children with congenital toxoplasmosis with intelligence quotient scores > or = 50 and visual acuity sufficient to cooperate with all of the intelligence quotient subscales had assessments of their vision, appearance of their retinas, and cognitive testing performed between 3.5 and 5 years of age. These evaluations took place between 1981 and 1998 as part of a longitudinal study to determine outcome of congenital toxoplasmosis. Children were evaluated at 3.5 or 5 (37 children) or both 3.5 and 5 (27 children) years of age. Cognitive function was measured using the Wechsler Preschool and Primary Scale of Intelligence-Revised. Wechsler Preschool and Primary Scale of Intelligence-Revised scale scores were compared for children grouped as those children who had normal visual acuity in their best eye (group 1), and those who had impaired vision in their best eye (acuity < 20/40) because of macular disease (group 2). Demographic characteristics were compared for children in the 2 groups. Test scores were compared between groups using all of the 3.5-year-old visits, all of the 5-year-old visits, and using each child's "last" visit (ie, using the 5-year-old test results when a child was tested at both 3.5 and 5 years of age or only at 5 years, otherwise using the 3.5-year-old test results). The results were similar and, therefore, only the results from the last analysis are reported here. RESULTS: There were 48 children with normal visual acuity in their best eye (group 1) and 16 children with impaired vision because of macular involvement in their best eye (group 2). Ethnicity and socioeconomic scores were similar. There was a significantly greater proportion of males in group 2 compared with group 1 (81% vs 46%). There was no significant diminution in Wechsler Preschool and Primary Scale of Intelligence-Revised test scores between 3.5 and 5 years of age for the 27 children tested at both of these ages. Verbal intelligence quotient, performance intelligence quotient, full-scale intelligence quotient scores, and all of the scaled scores except arithmetic and block design were significantly lower for children in group 2 compared with group 1. The majority of the differences remained statistically significant or borderline significant after adjusting for gender. However, the difference in overall verbal scores does not remain statistically significant. Mean +/- SD verbal (98 +/- 20) and performance (95 +/- 17) intelligence quotients were not significantly different for children in group 1. However, verbal (88 +/- 13) and performance intelligence quotients (78 +/- 17) were significantly different for children in group 2. For children in group 2, their lowest scale scores were in object assembly, geometric design, mazes, and picture completion, all timed tests that involved visual discrimination of linear forms with small intersecting lines. In the 2 scales scored that did not differ between groups 1 and 2, arithmetic and block design, timing and vision but not linear forms were components of the tasks. Children with monocular and binocular normal visual acuity did not differ in verbal, performance, or full-scale intelligence quotients or any of the subscale tests. Difficulty with sight or concomitant neurologic involvement also seemed to impact the ability to acquire information, comprehension skills, and vocabulary and performance in similarities testing. After controlling for gender, however, these differences were diminished, and there were no longer differences in overall verbal scores. As noted above, results were generally similar when all of the tests for 3.5-year-olds or 5-year-olds were analyzed separately. At the 3.5-year visit there were fewer significant differences between the 2 groups for the verbal components than at the 5-year visit. CONCLUSIONS: In children with congenital toxoplasmosis and bilateral macular disease (group 2) because of toxoplasmic chorioretinitis, scaled scores were lowest on timed tests that require discrimination of fine intersecting lines. Although the severity of ocular and neurologic involvement is often congruent in children with congenital toxoplasmosis, ophthalmologic involvement seems to account for certain specific limitations on tests of cognitive function. Children with such visual impairment compensate with higher verbal skills, but their verbal scores are still less than those of children with normal vision, and in some cases significantly so, indicating that vision impairment might affect other aspects of cognitive testing. Patterns of difficulties noted in the subscales indicate that certain compensatory intervention strategies to facilitate learning and performance may be particularly helpful for children with these impairments. These patterns also provide a basis for the development of measures of cognitive function independent of visual impairment.