Abstract
Purpose :
To describe clinical aspects and visual outcomes in individuals with ocular toxoplasmosis in Brazil.
Methods :
Individuals resident in Ribeirão Preto, Brazil who had serological evidence and clinical signs of ocular toxoplasmosis were included in this study. A uveitis specialist made the diagnosis of ocular toxoplasmosis from serological evidence of infection (T. gondii IgG and/or IgM positivity) and the presence of either focal retinitis or hyperpigmented retinochoroidal scars. The disease was defined as primary (active lesion in the absence of scars), recurrent active (active lesion in the presence of scars) or inactive (scars only). Atypical disease was included only when polymerase chain reaction revealed the presence of T. gondii DNA in aqueous humor. Subjects were examined by slit lamp and indirect ophthalmoscopy, and best corrected visual acuity (BCVA) was tested at all visits.
Results :
One hundred sixty-three subjects (51% men and 49% women) were included in the study (n=212 eyes). Twenty-two subjects (13.5%) were ≤ 17 years of age; 125 subjects were 18-64 years of age; and 16 subjects (9.8%) were ≥65 years of age. The form of ocular toxoplasmosis was primary active in 23 subjects (14.1%), recurrent active in 42 subjects (25.8%) and inactive in 98 subjects (60.1%). Most subjects presented with a single lesion (n=110; 51.9%), but 75 individuals (35.4%) had 2-4 lesions, and 27 had ≥5 lesions (12.7%). Lesions were central in 74 eyes (35%), peripheral in 101 eyes (47.6%%), and central and peripheral in 37 eyes (17.5%). Only 3 individuals (1.8%) presented with atypical ocular disease. Most subjects had T. gondii IgG+ IgM- serology (n=153; 93.9%);10 subjects (6.1%) had T. gondii IgG+ IgM+ serology. From the total of 198 affected eyes in which visual acuity could be measured, most (n=111; 56%) had final BCVA ≤20/40, and 40.5% of eyes (n= 45) were legally blind (BCVA <20/200). Visual acuity could not be measured in 14 eyes (6.6%) of infants. Three individuals presented bilateral BCVA <20/200.
Conclusions :
Ocular toxoplasmosis resulted in reduced vision in a significant number of individuals examined in this study. Prophylactic measures should be implemented for persons at high risk of vision loss from the disease, and the development of new therapeutic modalities should be a goal of future studies.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.