PURPOSE:Plasma Thymus and Activation Regulated Chemokine (TARC)is responsible for the trafficking of TH2 lymphocytes into sites of allergic inflammation. Recent studies suggested that TARC is a useful marker for chronic asthma, however, its role in asthmatic exacerbation is still unknown. The aim was to measure plasma concentration of TARC in asthmatic exacerbation, correlate the concentration with the severity of exacerbation, and to compare it with its level in stable condition and in normal controls.
METHODS:Plasma TARC concentration was assayed by ELISA in 30 asthmatic children during exacerbation, they were divided into three groups (mild, moderate and severe exacerbation) and in 20 healthy controls. The level was re-measured after control of exacerbation (stable condition). Peak Expiratory Flow Rate (PEFR), absolute eosinophilic count, oxygen concentration and total IgE were also measured in cases and controls.
RESULTS:Mean plasma TARC level in asthmatic exacerbation (409.3±248.3 pg/ml) was statistically significantly higher than its mean level in stable condition (96.2±126.7 pg/ml), and in controls (39.6±22.2 pg/ml) P = <0.0001. Also mean plasma TARC level was statistically significantly higher in stable condition than in controls, P= 0.05. Mean plasma TARC level in severe exacerbation ( 496.6±321.6 pg/ml) was higher than its mean level in moderate exacerbation (459.1±238.7 pg/ml) and in mild exacerbation (279.8±140.7 pg/ml) however, the difference was not statistically significant P = 0.12 .
CONCLUSION:Plasma TARC is elevated in asthmatic exacerbation but is not correlated with its severity.
CLINICAL IMPLICATIONS:Plasma TARC can be used to monitor occurence of asthma exacerbation but can not be used to assess its severity.
DISCLOSURE:Maged Eissa, No Financial Disclosure Information; No Product/Research Disclosure Information