Conclusions
Specific pro-inflammatory cytokines were increased in tears of patients with LDOD compared with those in the controls. The specific cytokine profiles observed in the tears of individuals with different LDOD subtypes may be associated with the unique aetiopathogenesis of these conditions.
Methods
Tear samples were collected from both eyes of 30 patients with unilateral LDOD: five patients with prelacrimal obstruction, five with acute dacryocystitis and 20 with chronic dacryocystitis. The contralateral eyes were used as controls. IFN-α2a, IFN-β, IFN-γ, IL-17A, IL-6, IL-8, tumour necrosis factor-alpha (TNF-α), vascular endothelial growth factor (VEGF)-A, induced protein-10 (IP-10) and monocyte chemotactic protein-1 (MCP-1) were quantified in all samples.
Results
The expression of eight cytokines (except for IP-10 and MCP-1) were significantly increased in the affected eyes compared with those in the control eyes. The levels of nine inflammatory cytokines (except for IP-10) in the affected eyes of patients with chronic dacryocystitis were higher than those in the affected eyes of patients with prelacrimal obstruction. In addition, patients with chronic dacryocystitis presented significantly higher IFN-γ level than those with prelacrimal obstruction or acute dacryocystitis. Interpretation & conclusions: Specific pro-inflammatory cytokines were increased in tears of patients with LDOD compared with those in the controls. The specific cytokine profiles observed in the tears of individuals with different LDOD subtypes may be associated with the unique aetiopathogenesis of these conditions.