Histamine-1 Receptors Expression in Primary Pterygium Tissue is Higher than Normal Conjunctival Tissue

BACKGROUND: Pterygium is an eye disease with multifactorial etiopathogenesis. Molecular factors such as cell proliferation and inflammatory mediators are associated with increased calcium mobilization and activation of nuclear factor kβ mediated by histamine-1 receptors (H1R). AIM: This study aims to determine whether the expression of H1R primary pterygium tissue is higher than normal conjunctival tissue and the expression of H1R based on pterygium grades. METHODS: This study was an analytic observational study with a case-control study approach at Sanglah General Hospital, Bali Mandara Eye Hospital, and Mangusada Hospital. The study was conducted from November 2017 to April 2018. The pterygium and conjunctival tissues obtained from 28 subjects in the same eye and examined for H1R expression by immunohistochemistry. RESULT: The results of this study obtained 64.3% of women with a mean age of 54.2 ± 7.8 years. There was no difference in mean H1R expression between pterygium grades in the final score (P = 0.759). There was a mean difference of H1R between primary pterygium (42.50) and normal conjunctival tissue (14.50) with P <0.001. Only tissue types affected the expression of H1R in the final score (B = 4.893; 95% CI 4.363-5.423; P <0.001). CONCLUSION: It was concluded that the expression of H1R primary pterygium tissue was higher in primary pterygium than normal conjunctival tissue.