Hydroxychloroquine treatment for primary Sjogren's syndrome: its effect onsalivary and serum inflammatory markers

Objective-To evaluate the effect of hydroxychloroquine treatment on interle ukin 6 (IL6), hyaluronic acid (HA), and soluble interleukin 2 receptor (sIL 2R) concentrations in the saliva and serum of patients with primary Sjogren 's syndrome (SS). Methods-Fourteen SS patients treated with hydroxychloroquine 200 mg/day for 12 months were investigated in an open prospective study. Clinical paramet ers of efficacy and routine biochemical and haematological data to assess d rug safety and tolerability were determined every three months. Salivary an d serum IL6, sIL2R, and HA values were determined at study entry, 6 and 12 months, using ELISA and radiometric assays. Results-After hydroxychloroquine treatment, salivary IL6 concentrations dec reased from 13.2 (1.2) to 7.3 (1.1) pg/ml (mean (SEM)) (p < 0.0001). Simila rly, salivary HA concentrations were also reduced from 577.8 (120) to 200 ( 34) ng/ml (mean (SEM) (p < 0.003). Serum IL6 concentrations decreased from 5.4 (0.6) to 2.9 (0.2) pg/ml (mean (SEM) (p < 0.001), while serum HA concen trations remained unchanged. No change has been detected in salivary or ser um sIL2R concentrations after 12 months of treatment with hydroxychloroquin e. Treatment also resulted in significant reduction in erythrocyte sediment ation rate, serum gamma globulin, and C reactive protein values while only partial clinical improvement was noted in some patients. A more pronounced decrease of salivary IL6 and HA levels was found in the two patients in who m a reduction in the swelling of the parotid gland was noted. Conclusion-In this open label study of hydroxychloroquine treatment for SS a significant reduction of some salivary inflammatory markers was seen at t he end of 12 months. Although during the treatment period only a partial cl inical effect could be noted, the findings suggest that a double blind cont rolled study of hydroxychloroquine in SS is indicated.