Ocular sarcoidosis: when should labial salivary gland biopsy be performed?

To assess the usefulness of a labial salivary gland biopsy (LSGB) in subsets of patients with uveitis.

A retrospective study of 115 consecutive patients with uveitis for whom a LSGB had been done because of suspected ocular sarcoidosis (n = 86) or unexplained uveitis (n = 29). Eighty-six patients had a suspicion of ocular sarcoidosis because of ocular features (n = 67), an elevated angiotensin converting enzyme (ACE) (n = 29), or because of CT findings (n = 32) suggestive of sarcoidosis. The biopsy results were analyzed together with their ophthalmological features and the results of other relevant examinations, such as the serum levels of ACE and a chest radiography or a CT scan.

Six of the 115 patients (5.2 %) with uveitis had sarcoid granulomas on the LSGB. At the end of the study, 32 patients had proven sarcoidois while 22 patients were considered as having either indeterminate or presumed sarcoidosis, according to the criteria of Abad et al. A raised ACE (p = 0.016) and a compatible radiology (p = 0.033) were related to a positive LSGB test, but not to the features of uveitis. Granulomas were only found in the LSGB of the patients with an elevated ACE or compatible CT scans.

In this study, the LSGB sensitivity (18.75 %) in the patients with proven sarcoidosis appears to be lower than in other reports. Our results suggest that this investigation is a possible method of tissue diagnosis in patients with raised ACE and/or CT scan pattern compatible with sarcoidosis, and should not be performed in patients with unexplained uveitis or because of their ophthalmological features.