Thirty‐five percent of pSS patients received hydroxychloroquine (HQ) treatment, and this group was significantly enriched in severe individuals (35 vs. 16%; P = 0.002), the presence of extra‐glandular manifestations (76 vs. 32%; P < 0.0001), and a trend to more marked alterations in levels of parameters associated with pathology such as lymphopenia, higher levels of IgG, and significantly lower levels of complement C3 (Appendix Table S1). The gene discussed is C3; the disease is peeling skin syndrome.