Background and aim In our study we aimed to show the relation between blood parameters and pulmonary function tests (PFT) with the asthma severity in patients with a diagnosis of asthma, and post-treatment changes in these parameters.

Method Children aged 0–14 years with asthma seen in our outpatient policlinic were prospectively evaluated. Complete blood count, ECP, specific IgE, Total IgE levels of the patients are recorded at the beginning of the study. Children >6 years performed spirometry. All patients filled a study registration form that includes major and minor risk factors. We classified the severity of the disease according to GINA (Global Initiative for Asthma) and we followed the treatment protocol. The severity of the disease did not show any significant correlations with the gender, atopic history and family history.

Results A statistically significant difference was found between the ECP, Total IgE levels and severity of asthma. We observed a decrease in the asthma severity during 2nd visit.

Conclusion Our results showed that serum ECP levels are significantly correlated with the severity of asthma and may be useful in the assessment of asthma control. Hence the PFT is quite difficult to perform in children, noninvasive parameters are becoming more important for the follow up of the treatment.