A Study of Relation between BCG Scar and Atopy in Schoolchildren of Zanjan City.

The prevalence of atopic disease in recent decades has been dramatically increased. It has been suggested that BCG vaccination may protect against development of allergic diseases.The purpose of this study was to identifying relation between scar of BCG vaccine and atopy. This cross-sectional study was done in 1000 children, 10-15 years of age, in Zanjan city. One thousand children (501 girls and 499 boys) were recruited in this study, 137, 121 and 141 cases of asthma, atopic dermatitis and allergic rhinitis, respectively were detected.Three hundred and three subjects had at least one of these disorders, which were diagnosed as atopy. There was reverse correlation between BCG scar and asthma (P=0.013), atopic dermatitis (P<0.01), and atopy (P<0.01). We did not find any association between the diameter of BCG scar and allergic rhinitis. Reverse correlation of asthma, atopic dermatitis and atopy with BCG scar are significant. This relied on history and symptoms of patients. Further studies with skin tests, measurements of total and specific IgE levels and spirometery are recommended.