Korean J Asthma Allergy Clin Immunol.  2006 Mar;26(1):52-58.

Methacholine and Adenosine 5'-monophosphate Challenge Tests in Children with Asthma: Relationship to Eosinophil Markers in Blood

Abstract

BACKGROUND
Bronchial hyperresponsiveness (BHR) in asthma is thought to be a consequence of underlying airway inflammation.
OBJECTIVE
The aim of this study was to assess the relationship between blood eosinophil inflammatory markers and bronchial responsiveness to both methacholine and adenosine 5'-monophosphate (AMP) in atopic children with mild to moderate asthma. METHOD: Ninety-eight atopic children with mild to moderate asthma were included. Methacholine, and AMP bronchial challenges were performed, and blood eosinophil count and serum eosinophil cationic protein (ECP) level were measured. Correlations between PC(20) to both bronchoconstrictor agents and blood eosinophil count or serum ECP levels were assessed. RESULT: Ninety-five (95.9%) and 92 (93.9%) of 98 subjects showed hyperreactivity to methacholine (PC(20)<16 mg/mL) and AMP (PC(20)<200 mg/mL), respectively. There was a significant association between methacholine PC(20) and AMP PC(20) (r=0.506, P<0.001). AMP PC(20) was significantly correlated with blood eosinophil count and serum ECP level (r=-0.386, P<0.001; r=-0.246, P<0.05, respectively). However, this significant association was not found between methatholine PC(20) and blood eosinophil count or serum ECP level. Multiple linear regression analysis revealed that only the blood eosinophil count was significantly associated with AMP PC(20).
CONCLUSION
AMP PC(20) seems to be more closely related to serum eosinophilic inflammatory markers than methacholine PC(20). This result suggests that AMP PC(20) is a very useful tool for evaluating eosinophilic inflammation in atopic asthma children.

MeSH Terms

Adenosine*
Asthma*
Bronchoconstrictor Agents
Child*
Eosinophil Cationic Protein
Eosinophils*
Humans
Inflammation
Linear Models
Methacholine Chloride*
Adenosine
Bronchoconstrictor Agents
Eosinophil Cationic Protein
Methacholine Chloride