Purpose: The aim of this study was to evaluate the structural changes of the airways using the endobronchial ultrasound (EBUS) in ACO patients compared to severe asthma and COPD patients.
Patients and Methods: The study included 17 patients with ACO, 17 patients with COPD and 33 patients with severe asthma. Detailed clinical data were obtained from all participants. Basic laboratory tests were performed, including measurement of eosinophil counts in blood and serum immunoglobulin E (IgE) concentrations. All patients underwent spirometry and bronchoscopy with EBUS (a 20‑MHz ultrasound probe) to measure the total thicknesses of the bronchial walls and their particular layers in segmental bronchi of the right lower lobe. EBUS allows to distinguish five layers of the bronchial wall. Layer 1 (L₁) and layer 2 (L₂) were analyzed separately, while the outer layers (layers 3– 5 [L_{3– 5}]) that correspond to cartilage were assessed together.
Results: In patients with ACO the thicknesses of the L₁ and L₂ layers, which are mainly responsible for remodeling, were significantly greater than in patients with COPD and significantly smaller than in patients with severe asthma (median L₁= 0.17 mm vs 0.16 mm vs 0.18 mm, p< 0.001; median L₂= 0.18 mm vs 0.17 mm vs 0.20 mm, p< 0.001, respectively). The thicknesses of the total bronchial walls (L₁+L₂+L_{3– 5}) and L_{3– 5} were significantly smaller in ACO and COPD patients compared to asthma patients (median L₁+L₂+L_{3– 5}= 1.2 mm vs 1.14 mm vs 1.31 mm, p< 0.001; median L_{3– 5}= 0.85 mm vs, 0.81 mm vs 0.92 mm, p=0.001, respectively).
Conclusion: The process of structural changes in the airways assessed by EBUS is more advanced in individuals with ACO compared to patients with COPD, and less pronounced compared to patients with severe asthma. It seems that EBUS may provide useful information about differences in airway remodeling between ACO, COPD and severe asthma.

Keywords: asthma-COPD overlap, airway remodeling, total bronchial wall, bronchial wall layers, endobronchial ultrasound

中文翻译：

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使用支气管内超声评估哮喘-慢性阻塞性肺疾病重叠的气道重塑


目的：本研究的目的是使用支气管内超声 (EBUS) 评估 ACO 患者与严重哮喘和 COPD 患者相比气道的结构变化。

患者和方法：该研究包括 17 名 ACO 患者、17 名 COPD 患者和 33 名严重哮喘患者。从所有参与者处获得了详细的临床数据。进行了基本的实验室测试，包括测量血液中的嗜酸性粒细胞计数和血清免疫球蛋白 E (IgE) 浓度。所有患者均接受了肺活量测定和使用 EBUS（20 MHz 超声探头）的支气管镜检查，以测量右下叶节段支气管中支气管壁的总厚度及其特定层。 EBUS 可以区分支气管壁的五层。第 1 层 (L ₁ ) 和第 2 层 (L ₂ ) 分别进行分析，而对应于软骨的外层（第 3-5 层 [L _3-5 ]）则一起评估。

结果： ACO 患者的 L ₁和 L ₂层厚度（主要负责重塑）显着大于 COPD 患者，且显着小于严重哮喘患者（中位 L ₁ = 0.17 mm vs 0.16 mm） mm vs 0.18 mm， p < 0.001；中值 L ₂ = 0.18 mm vs 0.17 mm vs 0.20 mm， p < 0.001。与哮喘患者相比，ACO 和 COPD 患者的总支气管壁厚度 (L ₁ +L ₂ +L _{3– 5} ) 和 L _{3– 5}显着较小（中位 L ₁ +L ₂ +L _{3– 5} = 1.2 mm vs 1.14 mm vs 1.31 mm， p < 0.001；中值 L _3-5 = 0.85 mm vs、0.81 mm vs 0.92 mm， p =0.001）。

结论：与 COPD 患者相比，EBUS 评估的 ACO 个体气道结构变化过程更先进，但与严重哮喘患者相比不太明显。 EBUS 似乎可以提供有关 ACO、COPD 和严重哮喘之间气道重塑差异的有用信息。


关键词：哮喘-COPD重叠，气道重塑，全支气管壁，支气管壁层，支气管内超声