[Differential diagnosis in infectious posterior uveitis].

Infectious aetiologies represent the largest entity in patients affected by posterior uveitis. As a single diagnosis, ocular toxoplasmosis ist the most frequently diagnosed infectious entity, wheres Behçet's uveitis represents the most frequently encountered immunologic aetiology. In acute posterior uveitis, an exact clinical diagnosis is sometimes prohibited by a dense vitreal infiltration. In this situation, the clinical course and progression of the disease may help in the differential diagnosis. Rapidly progressive instances such as viral retinal necrosis may be differentiated from cases of ocular toxoplasmosis and Behçet's disease, which tend to present in the office within one to two weeks of symptoms, and from other more slowly progressive diseases such as mycotic or nematode infections. The clinical picture at presentation is influenced by the duration of disease, underlying systemic conditions, and by the natural course of disease including the healing process and scare formation. Generally, visual function has to be assumed at risk, if a lesion is located close to the macula, if frequent recurrences increase the likelihood of macular involvement and, furthermore, if secondary complications affect the macula, e. g., macular oedema. In paediatric cases, the risk of amblyopia is frequently under-estimated, namely in the context of persistent dense vitreal infiltration. Therefore, a rapid interdisciplinary clinically tailored diagnostic access has to be reinforced in order to establish an early, targeted and etiologically based therapeutic strategy including steroid-sparing immunomodulating agents and possibly surgical alternatives.