Increased serum IL-10/IL-12 ratio in wheezing infants.

To investigate the association between various serum markers and atopic symptoms in the first year of life, and to evaluate the prognostic value of these markers for the development of wheezing and skin rash in the second year of life. Data of 86 children on the development of wheezing and skin rash in the first 2 years of life were collected prospectively, making use of parental completed questionnaires, weekly symptom cards, structured interview and physical examination. Serum markers (IL-10, IL-12, IL-13, eotaxin, sE-selectin, sICAM-1, sIL-2R) and total and specific IgE were determined at age 1. Children who developed wheezing in the first year of life had lower serum levels of IL-12 than children without symptoms (median 40.3 pg/ml vs. 49.0 pg/ml, p = 0.01) and a higher serum IL-10/IL-12 ratio (0.41 vs. 0.31, p = 0.001) at age 1. The IL-10/IL-12 ratio increased with an increasing number of wheezing episodes. Levels of sE-selectin in children with wheezing and in children with itchy skin rash in the first year of life were higher than in symptom free children (6.1 ng/ml and 5.9 ng/ml vs. 4.9 ng/ml, p = 0.01 and p = 0.03, respectively). Children who developed wheezing in the second year of life already had increased sICAM-1 levels at age 1. Children who developed wheezing in the first year of life showed a serum cytokine response that is skewed towards a T-helper 2 profile, with lower IL-12 levels and an increased IL-10/IL-12 ratio. Children who developed wheezing in the second year of life had elevated sICAM-1 levels at age 1. Follow-up of the children is needed to evaluate the prognostic value of various serum markers for the development of allergic disease in later childhood.