Airway wall thickness of allergic asthma caused by weed pollen or house dust mite assessed by computed tomography

Abstract

Purpose: Little was known about Airway wall thickness of asthma patients with different allergen allergy. So we explored the possible difference of Airway wall thickness of asthma patients mono-sensitized to weed pollen or HDM using high-resolution computed tomography.

Materials and methods: 85 severe asthma patients were divided into weed pollen group and HDM group according to relevant allergen. 20 healthy donors served as controls. Airway wall area, percentage wall area and luminal area at the trunk of the apical bronchus of the right upper lobe were quantified using HRCT and compared. The values of pulmonary function were assessed as well.

Results: There were differences between HDM group and weed pollen group in WA/BSA,WA% and FEF25-75% pred, and no significant difference in FEV1%pred, FEV1/FVC and LA/BSA. In weed pollen group, WA/BSA was observed to correlate with the duration of rhinitis, whereas in HDM group, WA/BSA and LA/BSA was observed to correlate with the duration of asthma. In weed pollen group, FEV1/FVC showed a weak but significant negative correlation with WA%, but in HDM group FEV1/FVC showed a significant positive correlation with WA% and a statistical negative correlation with LA/BSA. FEV1/FVC and FEF25-75% pred were higher and WA/BSA and LA/BSA were lower in healthy control group than asthma group. FEV1%pred and WA% was no significant difference between asthma patients and healthy subjects.

Conclusion: There are differences between HDM mono-sensitized subjects and weed pollen mono-sensitized subjects, not only in airway wall thickness, but also small airway obstruction.

Keywords: Airway wall thickness; Asthma; High-resolution computed tomography; House dust mite; Lung function; Weed pollen.