WOS: 000324363400024 PubMed: 23871269 Objectives: We investigated 1,25-dihydroxyvitamin D-3 [1,25(OH)(2)D-3] and specific immunoglobulin E (IgE) levels in children with recurrent tonsillitis (RT) plus allergic rhinitis (AR). Methods: Thirty children with RT + AR were included in the study group, and 30 healthy children comprised the control group. AR-related symptoms were determined using a symptom scale. 1,25(OH)(2)D-3 and specific IgE measurements were made in both groups. Results: The 1,25(OH)(2)D-3 value was significantly lower in the RT + AR group than in the control group. Specific IgE (mixed) panels were in normal limits in both groups; whereas specific IgE (mixed) grass pollen panel value of RT + AT group was significantly higher than that of the control group. Higher nasal itching, nasal obstruction, and concha edema scores were related to significantly higher specific IgE values for the (mixed) grass pollen panel, whereas higher sneeze scores were related to higher specific IgE values for the (mixed) pediatric panel. Conclusions: Children with grass pollen allergy may not be exposed to sufficient sunlight. With reduced 1,25(OH)(2)D-3, T helper cells may increase, and allergic response also increases. As allergic events increased, these children did not go outside and thus lacked sun exposure. This vicious cycle must be broken, and children with RT + AR should have sunlight exposure to increase 1,25(OH)(2)D-3 levels. (C) 2013 Elsevier Ireland Ltd. All rights reserved.