Exhaled breath temperature in asthmatic and healthy children: A case-control study

Introduction: Exhaled Breath Temperature (EBT) is a promising marker of airway inflammation. Studies on adult asthmatic patients show an increase of the EBT compared to healthy peers, but there are few studies in paediatric patients. Objective: The aim of this study is to compare the EBT of asthmatic children versus healthy controls, and to evaluate correlations with spirometry and exhaled nitric oxide (ENO). Methods: 56 patients were enrolled (36 M 20 F, aged 7-16 ys), 44 asthmatics and 12 controls. Anamnestic data, physical examination, and EBT values with "X-halo" (Delmedica), along with body and air temperature were evaluated. In asthmatic children we performed pulmonary function tests and ENO, too. Results: The median EBT was greater in asthmatics compared to controls (33.35°C vs 29.14°C, p=0.001). The average body temperature was similar in both groups (36.23°C vs 32.38 °C, p> 0.05) but the average air temperature was different (18.9°C vs 23.1°C, p Conclusions: There is a significant difference in median EBT between asthmatic and healthy children. We couldn9t find any correlation between EBT and FEV1 or ENO, possibly because the three tests reflect different phases of bronchial inflammation.