Age and ocular toxoplasmosis: a narrative review

Toxoplasma gondii is an extremely "successful" opportunistic parasite that infects most warm-blooded animals, including humans. While the infection is generally largely asymptomatic, the infection of the eye presenting as ocular toxoplasmosis (OT) is a potentially blinding consequence. OT remains the most common cause of infectious retinochoroiditis and places a considerable socio-economic burden on societies, particularly in developing countries. Age is one of several factors influencing the clinical presentation and outcomes of OT. Older patients often exhibit more severe disease manifestations, larger retinal lesions, and poorer visual outcomes compared to younger individuals. This disparity is attributed to immunosenescence, the age-related decline in immune function, which impairs the body's ability to control the infection effectively. Consequently, older individuals are at a higher risk of severe complications and recurrent episodes of inflammation. Understanding the interplay between age and immune response is essential for developing targeted treatment strategies and improving patient outcomes in OT.