Abstract
Background: Two large studies have recently reported an association between raised blood eosinophils and exacerbation frequency in older children (6 years onwards) and adults (Malinovschi et al 2013, Tran et al 2014). There is no data in preschool children (aged 5 years and younger). Acute wheeze is common in pre-schoolers hence it is important to identify and validate biomarkers associated with exacerbation prone wheeze in this age-group.
Aim: To investigate whether blood eosinophilia during acute wheeze is associated with exacerbation frequency in preschool children.
Methods: Children aged 6 months to 5 years treated for acute wheeze were eligible to participate. Details of exacerbation history were collected. We measured exacerbation frequency as number of exacerbations, quantified as above or below 3, in the previous 12 months. A blood sample was obtained and a leucocyte differential cell count was performed. We assessed the association between exacerbation frequency and blood eosinophilia using chi-square, with different absolute eosinophil count cut-offs, all reported in the literature, 0.2, 0.25, 0.3 and 0.4 x109/L.
Results: 60 children recruited (median age 33 months) were included in the analysis. There was no association between number of exacerbations (<3 n=32, >3 n=28) and blood eosinophilia. This was the case for all cut-offs; 0.2 (p=0.90), 0.25 (p=1.00), 0.3 (p=0.765) and 0.4 x109/L (p=0.527).
Conclusions: In our study, blood eosinophilia during acute wheeze was not associated with exacerbation frequency in pre-schoolers. This suggests that acute blood eosinophils do not identify children of this age-group with exacerbation prone wheeze.
- Copyright ©ERS 2015