Atopic dermatitis is a common, chronic, relapsing, allergic skin disease characterized by stronglypruritic eczematous skin lesions. Pruritus is the hallmark of atopic dermatitis, with a significant impact on quality of life for the patients. Many patients define their disease severity by the intensity of pruritus rather than by the appearance of skin lesions. Although the pruritus is one of the most essential symptoms of atopic dermatitis, its pathophysiology is still unclear. The lack of effect of antihistamines argues against a role of histamine in causing atopic dermatitis–related pruritus. Neuropeptides, proteases, kinins, and cytokines induce itching. In the early stages of atopic dermatitis Th2 cellsplay a significant role. Interleukin-31 is a cytokine produced by T cells that increases the survival ofhematopoietic cells and stimulates the production of inflammatory cytokines by epithelial cells. Our study aim is to investigate the correlation between the serum level of IL-31 and the severity of disease.A total of 80 participants with a diagnosis of atopic dermatitis based on the Hanifin and Rajka criteriaare selected from all patients of the National Dermatology center. A questionnaire consisting of theparticipant’s general information and disease history is obtained. The severity of disease is assessed by using SCORAD (Scoring atopic dermatitis) and patients with AD will be grouped into mild (< 25 points), moderate (25-50 points) or severe (> 50 points) disease groups. Serum IL-31 is measured using ELISA from peripheral blood.The main symptoms were pruritis (91,3%) and xerosis (78,8%). The serum IL-31 and NGF was higher in severe patients while the pruritus and sleep loss were stronger in those patients. Serum IL-31 was significantly correlated to Scorad index and sleep loss (р<0,05).IL-31 could be itch biomarkers. IL-31 has a role in pathogenesis of pruritus and atopic dermatitis.

IntroductionThe degree to which the change of season influences mood, energy, sleep, appetite, food preference,and the wish to socialize has been called “seasonality” [1]. In 1984 Rosenthal and associatesdescribed the syndrome of “seasonal affective disorder” (SAD), a condition where depressions in falland winter alternate with non-depressed periods in the spring and summer [5]. Seasonal AffectiveDisorder (SAD) is supposed to be caused by lack of daylight in winter [6]. Ulaanbaatar city is thecoldest capital in compared with medium temperature of the world. That’s why, it is an idea that wesupposed to there might be a seasonal affective disorder in this city. There is nothing to be studiedbefore related to this topic and that is our goal of the study.GoalTo determine a seasonal affective disorder in the adults of Ulaanbaatar cityMaterials and MethodsIn this study, we examined 560 healthy people between 20-60 aged livings in the Ulaanbaatar cityusing by Seasonal Pattern Assessment Questionnaire.ResultGender distribution showed an increased incidence of females (56.1%, 314 cases) compared withmale (43.9%, 246 cases). Distribution by age groups shows that 20-29 years were 237 (42.3%),30-39 years were 99 (17.6%), 40-49 years were 132 (23.5%), and 50-59 years were 92 (16.4%).According to the Seasonal Pattern Assessment Questionnaire, below 8 score was 323 (57.6%), 9-10 score 53 (9.4%), over the 11 score 184 (33%).ConclusionAccording to the questionnaire of Seasonal pattern assessment, 33 percent were seasonal affectivedisorder. It means Mongolian people of Ulaanbaatar have Seasonal affective disorder.