Objective:We aimed to share our observations on the demographics, clinical characteristics, and outcomes of lymphonodular hyperplasia (LNH) in children.Subjects and Methods:The study included children on whom colonoscopy was performed between January 2015 and May 2018 (n= 361). Demographics, treatment modalities, and outcomes of the patients with LNH were recorded.Results:LNH was found in 66 patients (18.3%; mean age 8.6 +/- 5.96 years, 59.1% male). We found that the etiologic factors were food hypersensitivity (FH) in 25 (37.8%), nonspecific colitis in 12 (18.2%), irritable bowel syndrome in 10 (15.2%), familial Mediter-ranean fever in 7 (10.6%), primary immunodeficiency in 4 (6.1%), and intestinal dysmotility, oxyuriasis, Crohn's disease, and giardiasis in 1 (1.5%) patient. Additionally, in the genetic analysis of patients with idiopathic LNH (n= 4), we detected heterozygoteMEFVmutations in all. Cow's milk and egg (25%) were the most common allergens in patients with FH. Symptoms of all patients (n= 25) improved after an elimination diet.Conclusions:LNH is a common finding in pediatric colonoscopies with a variety of etiologies ranging from FH and familial Mediterranean fever to immunodeficiency.