[Sarcoid uveitis: Diagnostic and therapeutic update]

Abstract

Uveitis is a common (20-50%) and early manifestation of sarcoidosis. Typical sarcoid uveitis presents with bilateral mutton fat keratic precipitates, iris nodules, and anterior and posterior synechia. Posterior involvement includes vitreitis, vasculitis and choroidal lesions. Long-term complications are common, and cystoid macular edema is the most important and sight-threatening consequence. Diagnostic work-up of sarcoidosis usually includes chest radiography or computed tomography scan, bronchoscopy with bronchoalveolar lavage, angiotensin converting enzyme, lysozyme, gallium scintigraphy and biopsy. The gold standard for the diagnosis of sarcoidosis should be obtained with histologic examination. However, an international workshop has recently established diagnostic criteria of "intraocular sarcoidosis" (sarcoidosis uveitis) on the basis of a combination of suggestive ophthalmological findings and laboratory tests, when biopsy is not performed or is negative. More recent techniques such as PET-scan and endoscopic ultrasound-guided fine-needle biopsy of intrathoracic nodes should be assessed in future prospective studies. Corticosteroids are the mainstay of treatment. Anterior and unilateral intermediate or posterior uveitis are usually treated with topical corticosteroids. Systemic corticosteroids are indicated in uveitis not responding to topical corticosteroids or in the presence of bilateral posterior involvement, especially with macular edema and occlusive vasculitis. In 5 to 20% of the patients who are corticosteroids resistant or require an unacceptable dose to maintain remission, additional immunosuppression is used, including methotrexate, leflunomide and mycophenolate mofetil. As in systemic sarcoidosis, infliximab has been recently suggested for refractory or sight threatening disease.