Airway Bacterial Load and Inhaled Antibiotic Response in Bronchiectasis


Por: Sibila, O, Laserna, E, Shoemark, A, Keir, HR, Finch, S, Rodrigo-Troyano, A, Perea, L, Lonergan, M, Goeminne, PC, Chalmers, JD

Publicada: 1 jul 2019
Resumen:
Rationale: The principal underlying inhaled antibiotic treatment in bronchiectasis is that airway bacterial load drives inflammation, and therefore antibiotic treatment will reduce symptoms. Objectives: To determine the relationship between bacterial load and clinical outcomes, assess the stability of bacterial load over time, and test the hypothesis that response to inhaled antibiotics would be predicted by baseline bacterial load. Methods: We performed three studies. Studies 1 and 2 were prospective studies including adults with bronchiectasis. Study 3 was a post hoc analysis of a randomized trial of inhaled aztreonam. A priori patients were divided into low (<10(5) cfu/g), moderate (10(5)-10(6) cfu/g), and high bacterial load (>= 10(7) cfu/g) using quantitative sputum culture. Measurements and Main Results: Bacterial load was a stable trait associated with worse quality of life and more airway inflammation in studies 1, 2, and 3. In study 3, patients with high bacterial load showed an improvement in the primary endpoint (Quality of Life-Bronchiectasis-Respiratory Symptoms Score at Week 4) in favor of aztreonam (mean difference of 9.7 points; 95% confidence interval, 3.4-16.0; P = 0.003). The proportion of patients who achieved an increase above the minimum clinically important difference was higher in the aztreonam group at Week 4 (63% vs. 37%; P = 0.01) and at Week 12 (62% vs. 38%; P = 0.01) only in high bacterial load patients. Conclusions: Improvement of quality of life with inhaled aztreonam was only evident in patients with high bacterial load. Bacterial load may be a useful biomarker of severity of disease and treatment response.

Filiaciones:
Sibila, O:
 Hosp Santa Creu & Sant Pau, Resp Dept, Barcelona, Spain

 Biomed Res Inst St Pau, Barcelona, Spain

Laserna, E:
 Hosp Comarcal Mollet, Mollet Del Valles, Spain

Shoemark, A:
 Univ Dundee, Scottish Ctr Resp Med, Dundee, Scotland

Keir, HR:
 Univ Dundee, Scottish Ctr Resp Med, Dundee, Scotland

Finch, S:
 Univ Dundee, Scottish Ctr Resp Med, Dundee, Scotland

Rodrigo-Troyano, A:
 Hosp Santa Creu & Sant Pau, Resp Dept, Barcelona, Spain

 Biomed Res Inst St Pau, Barcelona, Spain

Perea, L:
 Biomed Res Inst St Pau, Barcelona, Spain

Lonergan, M:
 Univ Dundee, Scottish Ctr Resp Med, Dundee, Scotland

Goeminne, PC:
 AZ Nikolaas, Dept Resp Med, St Niklaas, Belgium

 UZ Leuven, Dept Resp Med, Leuven, Belgium

Chalmers, JD:
 Univ Dundee, Scottish Ctr Resp Med, Dundee, Scotland
ISSN: 1073449X
Editorial
AMER THORACIC SOC, 25 BROADWAY, 18 FL, NEW YORK, NY 10004 USA, Estados Unidos America
Tipo de documento: Article
Volumen: 200 Número: 1
Páginas: 33-41
WOS Id: 000475464800013
ID de PubMed: 31109172
imagen Green Published

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