Retinitis is a posterior uveitis that affects mainly the retina. Retinitis lesions can be focal, multifocal, or disseminated (diffuse). Size and location (periphery/posterior pole/macula) are important. It is also essential to identify if the disease is restricted to the eye or if it is a part of serious underlying systemic disease (collagen vascular autoimmune disease, systemic infection, etc.).
Infectious, noninfectious, and masquerade syndromes can manifest as retinitis. Infectious entities, such as diffuse toxoplasmosis and acute retinal necrosis, must be excluded as therapy for noninfectious retinitis can have disastrous sequelae. Sarcoidosis, systemic lupus erythematosus (SLE), Churg–Strauss syndrome, Wegener’s granulomatosis, birdshot retinochoroiditis, and Adamantiades–Behcet’s disease can manifest as retinitis.