Objective: There is no established disease-modifying treatment of xerostomia and xerophthalmia in SS. This retrospective study was performed in order to evaluate the efficacy of HCQ for glandular function, i.e. saliva and tear production.
Methods: Fourteen patients with primary SS (pSS) were included (Group A). All patients were anti-Ro and/or -La antibody positive except one. Patients were treated with HCQ for a period of up to 6 months. Glandular function was determined by Saxon's and Schirmer's tests for the dominant eye at baseline and at the end of the treatment. We included a control group of 21 patients with objective sicca symptoms and positive alpha-fodrin antibodies (Group B).
Results: In patients with pSS (Group A), a significant increase in saliva production after HCQ treatment (P = 0.022) was observed. A subanalysis revealed that particularly the alpha-fodrin-positive patients responded to HCQ (P = 0.017 alpha-fodrin positive vs P = 0.4 alpha-fodrin negative). Interestingly, patients with sicca symptoms and alpha-fodrin antibodies (Group B) showed a significant increase in tear production (P = 0.001). In addition, there was a positive correlation between the alpha-fodrin IgA antibody concentration and the Schirmer's test at baseline (r = 0.66; P = 0.001) and after treatment (r = 0.6; P = 0.004) in this group.
Conclusions: HCQ treatment led to a beneficial effect on xerostomia in patients with pSS who lack severe organ manifestations. The response was greater in alpha-fodrin-positive patients.