PURPOSE: To evaluate the role of combined serum
angiotensin-converting enzyme (ACE) activity and whole-body
gallium (67GA) scanning in diagnosing
sarcoidosis in patients with features consistent with ocular
sarcoidosis but with normal or equivocal
chest radiographs. METHODS: Serum ACE levels and whole-body 67GA scans were obtained as part of the initial workup in 22 patients with active ocular
inflammation and ultimately biopsy-proven
sarcoidosis (sarcoid
uveitis group). A second group consisting of 70 patients with active
uveitis in whom
sarcoidosis also was considered a diagnostic possibility also was studied. All 70 patients ultimately had a definitive diagnosis other than
sarcoidosis (nonsarcoid
uveitis). All patients in this group also had a serum ACE and whole-body 67GA scan performed as part of their initial investigations. RESULTS: All patients in the sarcoid
uveitis group had either an elevated ACE level or an abnormal scan. In 16 of the 22 patients, results of both tests were abnormal. In no patient in the nonsarcoid
uveitis group were results of both tests abnormal. The sensitivity of an elevated ACE in diagnosing
sarcoidosis was 73% and the specificity was 83%. Using the combination of a positive 67GA scan and an elevated ACE, the specificity for diagnosis was 100% and the sensitivity was 73%. CONCLUSIONS: The combination of serum ACE level and whole-body 67GA scan increases the diagnostic specificity without affecting sensitivity in patients with clinically suspicious ocular
sarcoidosis who have normal or equivocal
chest radiographs.
