Background: The eye and its adnexa are frequently involved in sarcoidosis. Keratoconjunctivitis sicca is a typical manifestation that is believed to result from aqueous-layer deficiency in context with lacrimal gland disease. In this study we determined which layer of the tear-film might be involved.
Patients and methods: Fifty-six patients with clinically and histologically proven sarcoidosis were prospectively analysed for symptoms of dry eye, visual acuity, signs of blepharitis, Schirmer II test, rose bengal test, fluorescein staining, break-up time (BUT), and impression cytology (IPC). Deficiencies of the lipid, water and mucin layers were differentiated. The observations were compared with those from a control group of patients with symptoms of "dry eye" (n = 56).
Results: All patients in the control group, but only 20 sarcoidosis patients had dry eye symptoms. The BUT in the control group (7.2 +/- 5.4; mean +/- SEM) was shorter (p < 0.02) than in sarcoidosis patients (8.9 +/- 4.5; mean +/- SEM). Compared with the sarcoidosis patients, conjunctivitis occurred more frequently in the control group (p < 0.01). Rose bengal staining was positive in 18 sarcoidosis patients, and in 35 patients of the control group (p < 0.01). Signs of blepharitis, the results of Schirmer test, fluorescein staining and IPC, and the frequent incidence of deficiencies of aqueous layer, lipid layer and combined deficiencies of two or more layers did not differ significantly between the two groups. Deficiencies of the mucin layer were detected in 43 sarcoidosis patients, and in 51 patients in the control group (p < 0.05).
Conclusions: Tear-film deficiencies are common in sarcoidosis patients, even when clinical symptoms are absent. Observations herein suggest that patients with sarcoidosis may not only suffer from deficiencies of the aqueous layer, but also of the mucin and lipid layers.