Is Expression of the CD44 Adhesion Molecule on Eosinophils a Predictive Marker of BronchialAsthma in Infants with Wheezing

Overview

The differential diagnosis of asthma and relapsing obstructive bronchitis in infant and toddler age is stilldifficult. Bronchial asthma is a chronic inflammation of the respiratory pathways where a number of cells isinvolved, in particular mast cells, eosinophil cells and T-lymphocytes, but also epithelial cells. CD44 is an adhesivemolecule which can be detected also on the surface of activated eosinophils. In 21 children aged 7 - 38 monthsadmitted to the department with the diagnosis of obstructive bronchitis, on admission the level of serum eosinophilcationic protein was assessed as well as the absolute number of eosinophil leukocytes, the total serum immunoglobulinE and percentage of eosinophils with CD44 expression. A check-up examination of the mentionedparameters was made one month and one year after the baseline sampling.In the course of a one-year follow up based on the clinical picture and assembled results of three samplings in10 children the diagnosis of bronchial asthma was made and in 11 children the diagnosis of obstructive bronchitis.In asthmatic children as compared with the group with obstructive bronchitis a lower percentage ratio ofeosinophils with expression of CD44 was found: during the first examination 28.30% vs. 51.82%, during theexamination after one month 33.40% vs. 49.55% and during the examination after one year 33.40% vs. 59.60%.A negative correlation was found between the serum eosinophil cationic protein and percentage eosinophil ratiowith CD44 expression. After evaluation of the assembled results it is possible that a lower number of eosinophilcells with CD44 expression is a sign of activity of the eosinophil inflammation and the result of the passage ofeosinophils into the bronchial wall.Assessment of the percentage ratio of eosinophils with expression of CD44 may become a parameter in thedifferential diagnosis of bronchial asthma and relapsing bronchitis in infants and toddlers.

Key words:
bronchial asthma, obstructive bronchitis, eosinophil with expression of adhesion molecule CD44