Serpiginous choroiditis and infectious multifocal serpiginoid choroiditis.

Serpiginous choroiditis (SC) is a posterior uveitis displaying a geographic pattern of choroiditis, extending from the juxtapapillary choroid and intermittently spreading centrifugally. The choroiditis involves the overlying retinal pigment epithelium, and the outer retina. This intraocular inflammation typically involves both eyes in otherwise healthy, middle-aged individuals with no familial or ethnic predilection. Pathogenesis is unclear; based on limited histopathologic studies, however, favorable response to immunosuppressive agents, and the absence of association with systemic or local infectious or noninfectious diseases, an organ-specific autoimmune inflammation seems likely to be the underlying process. Patients, particularly from tuberculosis-endemic regions, may present with fundus changes simulating SC, but show evidence of active tuberculosis and/or the presence of mycobacterial DNA in the aqueous humor. This has been referred to as serpiginous-like choroiditis, but we prefer the description multifocal serpiginoid choroiditis (MSC). We present the distinguishing features of SC and infectious multifocal serpiginoid choroiditis simulating SC. The distinction is crucial to avoid unnecessarily treating SC with antimicrobial agents. Advances in diagnostic and imaging modalities can help differentiate SC from MSC. Novel local and systemic treatment approaches improve the outcome and preserve vision in SC.