Abstract

Abstract Objectives Some patients with sarcoidosis achieve spontaneous remission, whereas others repeatedly experience relapse. We examined differences in the clinical course of active sarcoidosis according to peripheral blood immunophenotypes before treatment. Methods This retrospective study compared peripheral blood immunophenotypes between patients with active sarcoidosis (n=28) and healthy control subjects (n=10). Patients with sarcoidosis were divided into the spontaneous remission group without treatment (n=9), the non-relapsed group after treatment (n=13), and the relapsed group after treatment (n=6) and were compared for peripheral blood immunophenotypes and background characteristics at baseline. Results Patients with sarcoidosis showed increases in activated T helper (Th) 1 cells, activated Th17 cells, and regulatory T (Treg) cell subsets. The proportion of effector Treg cells was highest in the spontaneous remission group, and the proportion of non-suppressive Treg cells was highest in the relapsed group. No differences were observed in the proportions of other CD4+ T cell subsets. The cut-off values for predicting spontaneous remission and relapse were calculated for the effector Treg/non-suppressive Treg ratio. As a result, A ratio ≥1.469 predicted spontaneous remission (75%), while ≤0.722 predicted relapse (66.7%). Conclusion Effector and non-suppressive Treg cell proportions before treatment may predict spontaneous remission and relapse in active sarcoidosis.