Amoxicillin concentrations in relation to beta-lactamase activity in sputum during exacerbations of chronic obstructive pulmonary disease

Marjolein Brusse-Keizer,1 Paul VanderValk,2 Rogier W van der Zanden,3 Lars Nijdam,4 Job van der Palen,1,5 Ron Hendrix,6,7 Kris Movig4 1Medical School Twente, 2Department of Pulmonary Medicine, Medisch Spectrum Twente, Enschede, 3Department of Clinical Pharmacy and Toxicology, Maastricht University Medical Centre, Maastricht, 4Department of Clinical Pharmacy, Medisch Spectrum Twente, 5Department of Research Methodology, Measurement and Data Analysis, University of Twente, 6Regional Laboratory of Public Health, Enschede, 7Department of Medical Microbiology, University Medical Centre Groningen, and University of Groningen, Groningen, the NetherlandsBackground: Acute exacerbations of chronic obstructive pulmonary disease (COPD) are often treated with antibiotics. Theoretically, to be maximally effective, the antibiotic concentration at sites of infection should exceed the minimum inhibitory concentration at which 90% of the growth of potential pathogens is inhibited (MIC90). A previous study showed that most hospitalized COPD patients had sputum amoxicillin concentrations&nbsp