Recurrent Chronic Obstructive Pulmonary Disease Exacerbations after Endobronchial Valve Implantation Are Associated with the Presence of Pseudomonas aeruginosa.
BACKGROUND
Endoscopic lung volume reduction by means of endobronchial valve implantation is an established therapy in patients with severe emphysema. However, long-term complications such as chronic obstructive pulmonary disease (COPD) exacerbations are a limitation of this method.


OBJECTIVE
As the mechanisms underlying increased rates of COPD exacerbations are unknown, the aim of our study was to determine whether infectious or inflammatory factors may contribute to these events and to investingate the consequent need for valve explantation.


METHODS
Tissue surrounding explanted endobronchial Zephyr valves was examined by microbiological, histological and cytological methods. Additionally, we performed a microbiological analysis of tracheal aspirates before both valve implantation and valve explantation. Moreover, blood samples were collected for the analysis of inflammatory markers.


RESULTS
Endobronchial valves were explanted from 16 patients. Reasons for explantation were frequent postprocedural COPD exacerbations (group 1: 8 patients) or loss of clinical benefit (group 2: 8 patients). Compared to group 2, the microbiological examinations of valve lavage and tracheal aspirates from patients in group 1 showed a higher detection of Gram-negative bacteria. In particular, infection with Pseudomonas aeruginosa was more predominant in group 1, while no presence could be detected in group 2. Blood inflammatory markers tended to be slightly higher in group 1 than in group 2; however, without reaching statistical significance.


CONCLUSIONS
Increased rates of COPD exacerbations after endobronchial valve implantation are associated with the presence of P. aeruginosa. The finding warrants further investigation.
Department of Internal Medicine II - Cardiology and Pulmonology, University of Bonn, Bonn, Germany.
Izabela
I
Tuleta
Carmen
C
Pizarro
Ernst
E
Molitor
Glen
G
Kristiansen
Georg
G
Nickenig
Dirk
D
Skowasch
D000368:Aged; D015415:Biomarkers / Q000097:blood; D001999:Bronchoscopy / Q000295:instrumentation*; D002097:C-Reactive Protein / Q000378:metabolism; D018450:Disease Progression; D005260:Female; D006801:Humans; D007249:Inflammation / Q000097:blood; D008168:Lung / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011552:Pseudomonas Infections / Q000097:blood / Q000150:complications*; D011550:Pseudomonas aeruginosa / Q000302:isolation & purification*; D029424:Pulmonary Disease, Chronic Obstructive / Q000097:blood / Q000382:microbiology* / Q000473:pathology / Q000628:therapy
D015415:Biomarkers; D002097:C-Reactive Protein