The exact pathogenesis of
pterygium has not been completely elucidated.
Growth factors have been considered to play a role in
pterygium formation.
Vascular endothelial growth factor (
VEGF) is one of the principal mediators of angiogenesis, fibroblast stimulation and tissue remodeling in allergic conditions. The aim of this study was to compare the association between
pterygium and
VEGF gene expression between atopic and non-atopic individuals. At first visit, all patients with
pterygium underwent blood tests, serum
immunoglobulin E (
IgE), serum
cytokines including
interleukin-4 (IL-4) and
interferon-γ (IFN-γ) and peripheral blood eosinophil count. After obtaining informed consents, questionnaires were used to obtain demographic and clinical data from patients who underwent
pterygium excision surgery. Skin prick test was performed to confirm or rule out atopy in 30 patients with (case group) and 30 patients without (control group) atopy.
Pterygium tissues were then removed by surgery. A semi-quantitative
reverse transcriptase polymerase chain reaction was performed to determine
VEGF gene expression in all patients. Our results illustrated that
VEGF mRNA expression in atopic patients was significantly higher than in the non-atopic group (P = 0.01). Eosinophil count, serum
IgE and
IL-4 were also significantly higher in atopic patients than in the non-atopic group (P = 0.03, 0.001 and 0.001, respectively). However, no significant difference was noted in serum IFN-γ between the two groups (P = 0.06). The excessive expression of
VEGF gene in
pterygium tissue of patients with atopy suggests that
growth factors may play a role in the pathogenesis of
pterygium or accelerate its formation.