Demystifying controversies in preschool wheeze

ABSTRACT

Introduction

Wheezing disorders in preschool children are common. Current treatment approaches assume all preschool wheezers are the same and will respond to a short course of oral corticosteroids (OCS) during acute attacks and subsequent maintenance inhaled corticosteroids (ICS) to prevent future attacks. But we have increasing evidence showing preschool wheezing disorders are markedly heterogeneous and the response to corticosteroids either during acute attacks or as maintenance therapy can be variable between patients and is determined by disease severity and underlying pathological phenotype.

Areas covered

The aim of this review is to discuss recent evidence which will help to explain a few critical pathophysiological concepts that are often misunderstood, thus helping to demystify the controversies that often surround preschool wheezing disorders and can contribute to ineffective management.

Expert opinion

Preschool wheezing disorders are distinct from school-age allergic asthma. There is little evidence to support the use of oral corticosteroids for acute attacks. A staged approach to confirm the diagnosis, and objective tests to determine the pathological phenotype of preschool wheeze is essential prior to initiating maintenance therapy to control symptoms and prevent attacks in children with recurrent preschool wheeze.

KEYWORDS:

• Allergic sensitization
• diagnosis
• eosinophils
• infection
• management
• neutrophils
• phenotype
• preschool wheeze

Article highlights

• Define preschool wheeze according to the presence of treatable traits; allergic, eosinophilic, type2; or non-allergic, neutrophilic, associated with viral/bacterial infection

• Clinical phenotypes are not distinct and are not stable over time, there is no relationship between clinical phenotypes and airway pathology in preschool wheeze

• Clinical phenotyping alone should not be used to help decide management of recurrent preschool wheeze

• Presence of aeroallergen sensitization and/or blood eosinophilia helps to identify children most likely to benefit from maintenance ICS for recurrent preschool wheeze

• There is little benefit of oral corticosteroids for acute attacks of preschool wheeze; unless very severe requiring hospitalization and associated with hypoxia

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was funded by the Action Medical research project grant (reference: GN2854).