목적: Gastroesophageal reflux is associated with ENT signs and symptoms. Gastric pepsin internalized by mucosal epithelial cells during reflux contributes to oxidative stress, inflammation, and carcinogenesis. In this study, we want to prove that the relationship between pepsin and tonsillitis. 방법:This study examined tonsillitis is due to pepsin-mediated gastric reflux. 28 children and 12 adults with tonsillitis prior to their surgical treatment were recruited. Bloods and tonsil tissues from each patient were harvested for lymphocyte, macrophage, and histological analysis, respectively. 결과:Lymphocyte levels from children were significantly higher than ones from adults. All of tonsil tissue from children expressed pepsin with different expression levels from each patient. In child group, the population of monocyte was significantly increased in the presence of activated Pepsin compared to absence of one on day 8 but not significant on day 15. However, the levels were not significant in adult group. And also, in child group, CD11c and CD163-positive cells were significantly increased by activated pepsin on day 8 after cultivation. However, not much difference found in adult group 결론:The interplay between hypersensitivity to pepsin reflux and tonsillar inflammation suggest children must be vulnerable to Pepsin environment than adults. Thus, this study provides that Pepsin-associated therapy would be warranted to identify and establish new therapeutic approaches for treating children with tonsillitis.