Identification of Pseudomonas aeruginosa and airway bacterial colonization by an electronic nose in Bronchiectasis

電子鼻用于綠膿桿菌及支氣管擴張氣道細菌分類鑒定研究

Guillermo Suarez-Cuartin, MD, PhD^1,2, Jordi Giner, RN, PhD^1,2, José Luis Merino, BSc, PhD³, Ana Rodrigo-Troyano, MD^1,2, Anna Feliu, RN^1,2, Lidia
Perea, BSc², Ferran Sanchez-Reus, MD, PhD^2,4, Diego Castillo, MD, PhD^1,2, Vicente Plaza, MD, PhD^1,2, James D. Chalmers, MD, PhD⁵, Oriol Sibila, MD, PhD^1,2.

¹Department of Respiratory Medicine, Hospital de la Santa Creu i Sant Pau, Universitat Autònoma de Barcelona. Barcelona, Spain.

²Institut d’Investigació Biomédica Sant Pau (IIB Sant Pau). Barcelona, Spain.

³Electronic Systems Group. Universitat de les Illes Balears. Palma de Mallorca, Spain.

⁴Department of Microbiology, Hospital de la Santa Creu i Sant Pau. Universitat Autònoma de Barcelona. Barcelona, Spain.

⁵Scottish Centre for Respiratory Research, University of Dundee. Dundee, UK.

Corresponding author:Dr. Oriol Sibila. Servei de Pneumologia, Hospital de la Santa Creu i Sant Pau. C/. Sant Antoni M. Claret 167, 08025 Barcelona (Spain). : osibila@santpau.cat

Keywords: Bronchiectasis; Electronic nose; Pseudomonas aeruginosa; Volatile organic compounds.

關鍵詞：支氣管疾病；電子鼻；假單胞菌；揮發性有機化合物。

Abstract
Rationale: Airway colonization by Potentially Pathogenic Microorganisms (PPM) in bronchiectasis is associated with worse clinical outcomes. The electronic nose is a non-invasive technology capable of distinguishing volatile organic compounds (VOC) in exhaled breath. We aim to explore if an electronic nose can reliably discriminate airway bacterial colonization in patients with bronchiectasis.
支氣管擴張中潛在致病微生物(PPM)的氣道定植與臨床結果相關。電子鼻是一種無創技術，能夠區分呼出的呼吸中的揮發性有機化合物(VOC)。目的探討電子鼻對支氣管擴張患者氣道細菌定植的鑒別診斷價值。

Methods: Seventy-three clinically stable bronchiectasis patients were included. PPM presence was determined using sputum culture. Exhaled breath was collected in Tedlar bags and VOC breath-prints were detected by the electronic nose Cyranose 320. Raw data was reduced to three factors with principal component analysis. Univariate ANOVA followed by post-hoc least significant difference test was performed with these factors. Patients were then classified using linear canonical discriminant analysis. Cross-validation accuracy values were defined by the percentage of correctly classified patients.

73例臨床穩定的支氣管擴張患者被納入研究。用痰液細胞培養法測定PPM的存在。將呼出的氣體收集在Tedlar袋中，用Cyranose320電子鼻檢測VOC呼吸指紋。通過主成分分析將原始數據簡化為三個因素。對這些因素進行單變量ANOVA分析，然后進行事后小顯著性差異檢驗。然后采用線性典型判別分析對患者進行分類。交叉驗證準確度值由正確分類患者的百分比定義。
Results: Forty-one (56%) patients were colonized with PPM. Pseudomonas aeruginosa (n=27, 66%) and Haemophilus influenzae (n=7, 17%) were the most common PPM. VC breath-prints from colonized and non-colonized patients were significantly different (accuracy of 72%, AUROC 0.75, p<0.001). VOC breath-prints from Pseudomonas aeruginosa colonized patients were significantly different from those of patients colonized with other PPM (accuracy of 89%, AUROC 0.97, p<0.001) and non-colonized patients (accuracy 73%, AUROC 0.83, p=0.007).

41例(56%)患者被PPM定殖。銅綠假單胞菌(n=27，66%)和流感嗜血桿菌(n=7，17%)是見的PPM。結腸和非結腸患者的VC呼吸圖有顯著差異(準確度72%，AUROC 0.75，P<0.001)。銅綠假單胞菌定殖患者的VOC呼吸圖譜與其他PPM定殖患者(準確度89%，AUROC 0.97，P<0.001)和非定殖患者(準確度73%，AUROC 0.83，P=0.007)有顯著差異。
Conclusions: An electronic nose can accuray identify VOC breath-prints of clinically stable bronchiectasis patients with airway bacterial colonization, especially in those with Pseudomonas aeruginosa.

電子鼻能準確穩定的識別臨床支氣管擴張患者氣道細菌定植的VOC呼吸圖譜，尤其是銅綠假單胞菌。