[Sarcoidosis and uveitis : An update].

Ocular involvement in sarcoidosis is present in up to one third of patients and is frequently manifested before the underlying systemic disease has been diagnosed. With a view to the therapeutic consequences an early diagnosis of the underlying disease is advantageous. In cases of visual loss early diagnostic measures include invasive procedures, such as ultrasound-guided bronchoalveolar lavage and transbronchial biopsy, if nodular conjunctival or cutaneous manifestations which would confirm the diagnosis are not present. Sufficiently sensitive biomarkers of disease activity have not yet been identified. As elevated activity of angiotensin-converting enzyme (ACE) and lysozyme are associated with disease activity they may be supportive of but not specific for the diagnosis. Other indicators include calcemia, calciuria, augmented activity of hepatic enzymes, cutaneous anergy and hilar changes in the lungs. In patients with newly diagnosed anterior uveitis presenting with granulomatous mutton-fat corneal precipitates, snow balls and vitreous body base condensates with mild retinal periphlebitis in intermediate uveitis as well as multifocal choroiditis (creamy choroidal lesions at different stages of activity and approximately 500 µm in diameter), a diagnosis of sarcoidosis has to be considered and tuberculosis should be excluded, even in the absence of a known systemic disease. Anterior uveitis is frequently a self-limiting condition, which can be well-controlled with topical steroids. On the other hand, intermediate, posterior and panuveitis are typically associated with a chronic course and require systemic therapy to prevent severe loss of vision. If the response to systemic corticosteroids is insufficient, treatment with immunomodulatory agents and biologics is initiated at progressively earlier stages, with a view to averting permanent organ damage and frequently with a positive impact on the short and long-term outcomes, even in therapy-refractive cases.