When a patient has a granulomatous uveitis and investigations reveal an anergy to tuberculin, an enlargement of the hilar glands on chest x-ray film, and raised serum immunoglobulin levels, a diagnosis of sarcoidosis can be made with confidence. Histological confirmation from a biopsy of a lymph node or the conjunctiva is hardly necessary in such cases.
However, when the ocular findings are less typical, as for example in lesions of the optic disc (see p 1194) or of the lacrimal sac (see p 1198) and when the typical roentgenographic findings are absent, the diagnosis of sarcoidosis requires further evidence.
The Kweim-Siltzbach test is positive in 80% of cases of sarcoidosis and is easy to perform, but it does necessitate the use of a potent antigen that is not commercially available and has to be obtained from the spleen of a patient with active sarcoidosis. Care must be taken to exclude
Perkins ES. Ocular Sarcoidosis. Arch Ophthalmol. 1981;99(7):1193. doi:10.1001/archopht.1981.03930020067002