Abstract
Background: Preschool wheezing is common and many children experience exacerbations and are well in between. Raised blood eosinophils in older children are associated with exacerbation-prone wheeze, but there are currently no biomarkers to predict near-future exacerbations in preschoolers. There is evidence suggesting that eosinophils are acutely activated during an exacerbation using urinary markers, however, it is unknown whether blood eosinophil numbers fluctuate between the time of an exacerbation and stable disease. Objective: To investigate whether, in children with preschool wheeze, blood eosinophil numbers are different during an acute wheezing episode compared with periods of stable disease. Methods: Blood samples were taken from children aged 10 months to 6 years, presenting with acute, doctor-diagnosed wheeze, and tested for absolute leukocyte differential cell numbers. A repeat blood sample was obtained in a subset of children after full recovery. Main Outcome Measure: Difference between blood eosinophil counts during an acute wheezing episode and after recovery (stable disease) was also obtained. Results: Eighty-five children participated in this study, with 68 recruited during an acute wheezing episode (median absolute blood eosinophil numbers 0.10 × 109/L [range 0.00-2.41]) and 17 healthy controls. There was no significant difference in absolute blood eosinophil numbers between the acutely wheezy children when compared with the controls (median 0.17 × 109/L range 0.00-0.83). Absolute blood eosinophil numbers during stable disease were significantly greater (median 0.43 × 109/L; range 0.12 × 1.25 × 109/L) compared with periods of exacerbation (median 0.11 × 109/L range 0.01-1.10) in 20 children in whom paired blood samples were available. Absolute blood lymphocyte numbers were also higher during periods of stable disease, whereas absolute blood neutrophil numbers were higher during the exacerbation. Conclusions: Greater numbers of blood eosinophils are present during stable disease compared with the exacerbation state. This is an important consideration when planning future studies using blood eosinophils as a biomarker in wheezy preschool children.
Highlights
Wheezing in the first six years of life is extremely common and affects up to half of all preschoolers by their fifth birthday[1,2]
There was no significant difference in blood eosinophil counts between children with preschool wheeze and healthy controls when measured acutely whereas eosinophil counts were significantly higher in children with stable preschool wheeze compared to controls
Blood neutrophil counts fell between the acute episode and after recovery whereas blood lymphocyte counts rose similar to eosinophil counts
Summary
Wheezing in the first six years of life is extremely common and affects up to half of all preschoolers by their fifth birthday[1,2]. One important clinical difficulty when dealing with wheezy preschoolers is how to identify children with exacerbation-prone wheeze for a trial of preventer medication. In addition there are concerns regarding potential side effects of this treatment the reduction in growth velocity[8]. This results in reluctant prescribing and adherence to this medication. Preschool wheezing is common and many children experience exacerbations and are well in between. Raised blood eosinophils in older children are associated with exacerbation-prone wheeze but there are currently no biomarkers to predict near-future exacerbations in preschoolers. There is evidence suggesting eosinophils are acutely activated during exacerbations of preschool wheeze which subsides after recovery using urinary w ie ev markers it is unknown whether the profile of leucocytes in the blood differ
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
