Longitudinal Study of New Eye Lesions in Treated Congenital Toxoplasmosis Laura Phan, MPH, 1 Kristen Kasza, MS, 2 Jessica Jalbrzikowski, BA, 1 A. Gwendolyn Noble, MD, PhD, 3 Paul Latkany, MD, 1,4 Annie Kuo, BS, 1 William Mieler, MD, 1 Sanford Meyers, MD, 1 Peter Rabiah, MD, 1 Ken Boyer, MD, 5 Charles Swisher, MD, 3 Marilyn Mets, MD, 3 Nancy Roizen, MD, 1,6 Simone Cezar, BS, 1 Jack Remington, MD, 7 Paul Meier, PhD, 1,8 Rima McLeod, MD, 1 Toxoplasmosis Study Group* 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. Ophthalmology 2008;115:553–559 © 2008 by the American Academy of Ophthalmology. The natural history of chorioretinal lesions in a cohort of children with congenital toxoplasmosis treated for their first year of life with pyrimethamine, sulfadiazine, and leucov- orin has not previously been reported, although early child- hood outcomes after other treatment regimens have been described. Chorioretinal disease in children with congenital toxoplasmosis, who were either untreated or treated 1 month postpartum, has been reported to be a relapsing recrudescent disease with new eye lesions that have significant impact on vision in more than 85% of affected individuals by the time they reach their teenage years. 1,2 Herein, we describe the natural history of chorioretinal lesions in a cohort of con- Originally received: November 7, 2006. Final revision: June 6, 2007. Accepted: June 9, 2007. Available online: September 6, 2007. Manuscript no. 2006-1285. 1 University of Chicago School of Medicine, Chicago, Illinois. 2 Department of Health Studies, University of Chicago, Chicago, Illinois. 3 Children’s Memorial Hospital, Chicago, Illinois. 4 New York University School of Medicine and New York Eye & Ear Infirmary, New York, New York. 5 Rush University Medical Center, Chicago, Illinois. 6 Cleveland Clinic, Cleveland, Ohio. 7 Palo Alto Medical Foundation, Stanford University, Palo Alto, California. 8 Columbia University, New York, New York. Presented as a poster at: American Academy of Ophthalmology Annual Meeting, October 2005, Chicago, Illinois. Supported in part by the National Institutes of Health, Bethesda, Maryland (grant no. RO1 AI 1-27530-15); Research to Prevent Blindness Foundation, New York, New York; Hyatt Hotel Foundation; United Airlines Friendly Skies; Braniff International Airways; Southwest Airlines, Dallas, Texas; American Airlines, Fort Worth, Texas; Air Canada, Dorval, Canada; Angel Flight America, Addison, Texas; and the Langel, Morel, Kiewit, Rooney- Alden, Blackman, Rosenstein, Kapnick, Cussen, and Singer families. There is no conflict of interest with any of the authors involved in the study. Correspondence and reprint requests to Rima McLeod, MD, University of Chicago, AMBH S 206, 5841 South Maryland Avenue, Chicago, IL 60637. E-mail: rmcleod@midway.chicago.edu. *Other members of the Study Group are listed in “Appendix” (available at http://aaojournal.org). 553 © 2008 by the American Academy of Ophthalmology ISSN 0161-6420/08/$–see front matter Published by Elsevier Inc. doi:10.1016/j.ophtha.2007.06.022