Relationship of Serum Total IgE Levels, Specific IgE Levels and Peripheral Total Eosinophil Count in Patients of Younger Than 2 Years with Allergic Diseases.

Rationale: Serum total IgE (tIgE), specific IgE (sIgE) and total eosinophil count (TEC) are indicators of allergic diseases and  the severity allergic diseases. We sought to evaluate the association between the indicators of allergic diseases in children younger than 2 years of age.

Methods: Children younger than 2 years took allergy testing between 2012 and 2013 were recruited. They were divided into four groups with atopic dermatitis (AD), allergic rhinitis (AR), bronchial asthma (BA) or urticarial (UT). Total IgE, sIgE levels and TEC were measured. Specific IgE was measured by ImmunoCAP and the levels were classified in seven steps of 0-6.

Results: Total 190 patients were recruited: AD (n=54), AR (n=16), BA (n=27), UT (n=25), other diseases (acute bronchiolitis, acute sinusitis, milk allergy, acute bronchitis; n=68). The mean  tIgE concentration and TEC were highest in AD (124 IU/mL and 673/mm³, respectively). We analyzed correlation of tIgE and TEC between ImmunoCAP ASM class II and ImmunoCAP ASM class I or less group. There was no significant correlation in allergic diseases and urticaria. (AR: r=0.33 p=0.25, AD: r=0.15, p=0.25, BA: r=0.11 p=0.57, UT: r=0.10, p=0.62) TEC showed significant difference between allergic diseases group (AD, AR, BA) and control groups of acute UT and other diseases (448.8/mm³ vs. 310.7/mm³, p=0.03) although tIgE did not show any difference (140.8 IU/mL vs. 116.1/mL, p=0.88)

Conclusions: Measuring the peripheral blood total eosinophil count may help diagnose allergic diseases in patient less than 2 years. Specific IgE levels were not statistically significantly between allergic diseases