The CD4/CD8 ratio in vitreous fluid is of high diagnostic value in sarcoidosis

Abstract

Purpose: Sarcoidosis is an idiopathic inflammatory disorder involving multiple organs, and ocular manifestation (represented by granulomatous uveitis) is one of the common features. A well-known immunologic feature in sarcoidosis is an increased CD4+ helper T-cell type 1 lymphocyte subset in bronchoalveolar lavage (BAL) fluid. The current study investigated the vitreous lymphocyte subsets of ocular sarcoidosis to elucidate the immunologic features of this disorder in the eye.

Design: Case-control study.

Participants and controls: Fifty-one eyes of 38 patients with ocular sarcoidosis, confirmed by international diagnostic criteria, were enrolled in this study. Twenty-seven eyes of 26 patients with other causes of uveitis were enrolled as nonsarcoid controls.

Methods: Evaluation of diagnostic tests for cell profiles of ocular sarcoidosis. Lymphocytes in the vitreous samples were analyzed by cytology, polymerase chain reaction, and flow cytometry. Peripheral blood was also obtained from each patient and analyzed in comparison with the vitreous samples.

Main outcome measures: CD4/CD8 ratios of vitreal and peripheral T lymphocytes.

Results: CD4/CD8 ratios of the vitreous T lymphocytes were significantly higher in ocular sarcoidosis than in nonsarcoidosis vitreous samples. In the patients with ocular sarcoidosis, the CD4/CD8 ratios of vitreal T lymphocytes were significantly higher than the CD4/CD8 ratios of peripheral T lymphocytes. No significant differences were found between the CD4/CD8 ratios of vitreal and peripheral T lymphocytes in the patients without sarcoidosis. Moreover, the CD4/CD8 ratios of peripheral T lymphocytes in the patients with ocular sarcoidosis were significantly higher than in patients without sarcoidosis. The sensitivity and specificity of the vitreal CD4/CD8 ratio were 100% and 96.3%, respectively, for the diagnosis of ocular sarcoidosis.

Conclusions: Our findings suggest that the CD4/CD8 ratio of vitreous-infiltrating lymphocytes has high diagnostic value in ocular sarcoidosis, comparable to that of the CD4/CD8 ratio in BAL fluid lymphocytosis for pulmonary sarcoidosis. Furthermore, a high CD4/CD8 ratio of peripheral blood T lymphocytes should be one of the laboratory findings for ocular sarcoidosis. Diagnostic vitrectomy using flow cytometric analysis may be a useful adjunct for the diagnosis of ocular sarcoidosis, particularly in complex cases.