Asthma-predictive-index, bronchial-challenge, sputum eosinophils in acutely wheezing preschoolers.

BACKGROUND: Most preschoolers with viral wheezing exacerbations are not atopic. AIM: To test in a prospective controlled trial whether wheezing preschoolers presenting to the ED are different from the above in three different domains defining asthma: the atopic characteristics based on stringent asthma predictive index (S-API), the characteristics of bronchial hyper-responsiveness (BHR), and airway inflammation. METHODS: The S-API was prospectively collected in 41 preschoolers (age 31.9 ± 17.4 months, range; 1-6 years) presenting to the ED with acute wheezing and compared to healthy preschoolers (n = 109) from our community (community control group). Thirty out of the 41 recruited preschoolers performed two sets of bronchial challenge tests (BCT)-(methacholine and adenosine) within 3 weeks and following 3 months of the acute event and compared to 30 consecutive ambulatory preschoolers, who performed BCT for diagnostic workup in our laboratory (ambulatory control group). On presentation, induced sputum (IS) was obtained from 22 of the 41 children. OUTCOMES: Primary: S-API, secondary: BCTs characteristics and percent eosinophils in IS. RESULTS: Significantly more wheezing preschoolers were S-API positive compared with the community control group: 20/41 (48.7%) versus 15/109 (13.7%, P < 0.001). All methacholine-BCTs-30/30 (100%) were positive compared with 13/14 (92.8%) in the ambulatory control group (P = 0.32). However, 23/27 (85.2%) were adenosine-BCT positive versus 3/17 (17.5%) in the ambulatory control group (P < 0.001). Diagnostic IS success rate was 18/22 (81.8%). Unexpectedly, 9/18 (50.0%) showed eosinophilia in the IS. CONCLUSIONS: Wheezing preschoolers presenting to the ED is a unique population with significantly higher rate of positive S-API and adenosine-BCT compared with controls and frequently (50%) express eosinophilic airway inflammation.

Hypertonic saline and acute wheezing in preschool children.

BACKGROUND: Most acute wheezing episodes in preschool children are associated with rhinovirus. Rhinovirus decreases extracellular adenosine triphosphate levels, leading to airway surface liquid dehydration. This, along with submucosal edema, mucus plaques, and inflammation, causes failure of mucus clearance. These preschool children do not respond well to available treatments, even oral steroids. This calls for pro-mucus clearance and prohydration treatments such as hypertonic saline in wheezing preschool children. METHODS: Randomized, controlled, double-blind study. Forty-one children (mean age 31.9 ± 17.4 months, range 1-6 years) presented with wheezing to the emergency department were randomized after 1 albuterol inhalation to receive either 4 mL of hypertonic saline 5% (HS) (n = 16) or 4 mL of normal saline (NS) (n = 25), both with 0.5 mL albuterol, twice every 20 minutes in the emergency department and 4 times a day thereafter if hospitalized. The primary outcome measured was length of stay (LOS) and the secondary outcomes were admission rate (AR) and clinical severity score. RESULTS: The LOS was significantly shorter in the HS than in the NS group: median 2 days (range 0-6) versus 3 days (range 0-5) days (P = .027). The AR was significantly lower in the HS than the NS group: 62.2% versus 92%. Clinical severity score improved significantly in both groups but did not reach significance between them. CONCLUSIONS: Using HS inhalations significantly shortens LOS and lowers AR in preschool children presenting with an acute wheezing episode to the emergency department.