THE VALUE OF COMBINED SERUM ANGIOTENSIN-CONVERTING ENZYME AND GALLIUMSCAN IN DIAGNOSING OCULAR SARCOIDOSIS

Purpose: To evaluate the role of combined serum angiotensin-converting enzyme (ACE) activity and whole-body gallium ((67)GA) scanning in dia gnosing sarcoidosis in patients with features consistent with ocular s arcoidosis but with normal or equivocal chest radiographs. Methods: Se rum ACE levels and whole-body (67)GA scans were obtained as part of th e initial workup in 22 patients with active ocular inflammation and ul timately biopsy-proven sarcoidosis (sarcoid uveitis group). A second g roup 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 (67)GA scan performed as part of their initial investi gations. 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 u veitis group were results of both tests abnormal, The sensitivity of a n elevated ACE in diagnosing sarcoidosis was 73% and the specificity w as 83%, Using the combination of a positive (67)GA scan and an elevate d ACE, the specificity for diagnosis was 100% and the sensitivity was 73%. Conclusions: The combination of serum ACE level and whole-body (6 7)GA scan increases the diagnostic specificity without affecting sensi tivity in patients with clinically suspicious ocular sarcoidosis who h ave normal or equivocal chest radiographs.