Abstract
Purpose :
Thyroid eye disease (TED) serves as the predominant extrathyroidal manifestation of Graves’disease (GD). Clinical studies have indicated a higher prevalence of lacrimal gland involvement in patients with TED than healthy controls. However, the etiology of lacrimal gland enlargement and the resulting ocular symptoms have not been evaluated comprehensively. This study aimed to investigate the clinical and immunological characteristics of lacrimal gland enlargement in patients with TED.
Methods :
This retrospective study collected clinical data from patients who were initially diagnosed with TED at the First Affiliated Hospital, Sun Yat-sen University, between 2019 and 2023. TED patients were divided into two groups based on measurements of orbital magnetic resonance imaging (MRI): the enlarged lacrimal gland (ELG) and normal lacrimal gland (NLG) groups. Relevant ocular evaluations included clinical activity score (CAS), proptosis measurement, tear film break-up time (BUT), and Schirmer scores (Schirmer I). Immunological examinations included serum cytokines and lymphocyte subsets in peripheral blood. These data were comprehensively collected and analyzed.
Results :
A total of 123 patients diagnosed with TED were included in this study, among whom bilateral lacrimal gland enlargement was observed in 87 patients. The ELG group had a younger age and a higher proportion of males compared to the NLG group. The presence of lacrimal gland enlargement in TED patients was associated with a higher likelihood of active TED (CAS≥3). Moreover, in comparison to the NLG group, patients with TED in the ELG group demonstrated a shorter BUT time, an elevated Schirmer score exceeding the upper limit of normal, and exacerbated exophthalmos. However, there was no difference in serum cytokines between the ELG and the NLG groups. In the ELG group, there was a significantly higher proportion of CD8+ T cells among subpopulations of lymphocytes compared to the NLG group. Further functional analysis of T lymphocytes demonstrated a decreased percentage of PD-1+ CD8+ T cells in the ELG group.
Conclusions :
Lacrimal gland enlargement in TED indicated active TED, dry eye, tearing, and worse exophthalmos. Our findings suggested that increased and activated CD8+ T cells were positively correlated with lacrimal gland enlargement in TED.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.