Point‐of‐Care Blood Eosinophils to Predict Preschool Wheeze Attacks

BACKGROUND: Post hoc analysis of clinical trials shows blood eosinophil counts (BEC) predict future preschool wheeze attacks; however, prospective usefulness in a clinical setting is unreported. We assessed the feasibility of point-of-care (POC) eosinophil measurements in preschool wheezers and related BEC to symptoms, lung function, and utility in predicting attacks. METHODS: Children aged 1-5 years with recurrent wheeze underwent finger-prick sampling during the outpatient clinic for POC eosinophils, forced oscillation technique (FOT) and/or spirometry, and symptom score (TRACK questionnaire). The utility of BEC and/or the other tests in predicting wheeze attacks in the subsequent 3 months was analysed by comparing those with and without an attack and using a predictive decision tree (DT) model. RESULTS: /L, p = 0.03 and median 6% vs. 4%, p < 0.01). The DT model showed children with BEC ≥ 4% and TRACK score < 75 were more likely to have a future attack (probability 0.63). CONCLUSION: POC blood eosinophils were feasible in a clinical setting. Our preliminary data suggest elevated BEC with a low symptom score predicts a wheeze attack within 3 months.