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.
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).
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.
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.