Response to HCQ
In this study, there were 37 patients who had records of platelet counts at 3 months from HCQ initiation, and 5 patients were not involved in this analysis because of missing data. 21 (56.8%) patients achieved CR/R at 3 months from HCQ initiation, and 16 (43.2%) patients had no response to the treatment. According to the response to HCQ at 3 months from initiation, we divided the 37 patients into two groups: the response group and the no response group. Differences between the two groups are listed in Table 2. There was no difference in the presence of symptoms associated with autoimmune diseases, baseline ANA positivity, antiphospholipid antibodies positivity, Low C3/C4, and autoimmune disease progression between the two groups. In the response group, 71.4% (15/21) of patients achieved long-term response (including 2 achieved R and 13 achieved CR at 12 months), and 9.5% (2/21) of patients lost CR/R. Most of patients with no response to HCQ received monotherapy of HCQ (10/16, 62.5%), while most of patients with response to HCQ received combined therapy (17/21, 81.0%).