Airway bacteria measured by quantitative polymerase chain reaction and culture in patients with stable COPD: relationship with neutrophilic airway inflammation, exacerbation frequency, and lung function

Mona Bafadhel1 Respiratory Medicine Unit, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UKCorrespondence[email protected]

Koirobi Haldar2 Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, UK

Bethan Barker2 Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, UK;3 Institute for Lung Health, National Institute for Health Research Respiratory Biomedical Research Unit, Glenfield Hospital, University of Leicester, Leicester, UK

Hemu Patel4 Department of Clinical Microbiology, University Hospitals of Leicester NHS Trust, Leicester, UK

Vijay Mistry2 Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, UK;3 Institute for Lung Health, National Institute for Health Research Respiratory Biomedical Research Unit, Glenfield Hospital, University of Leicester, Leicester, UK

Michael R Barer2 Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, UK;3 Institute for Lung Health, National Institute for Health Research Respiratory Biomedical Research Unit, Glenfield Hospital, University of Leicester, Leicester, UK;4 Department of Clinical Microbiology, University Hospitals of Leicester NHS Trust, Leicester, UK

Ian D Pavord1 Respiratory Medicine Unit, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK

Christopher E Brightling2 Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, UK;3 Institute for Lung Health, National Institute for Health Research Respiratory Biomedical Research Unit, Glenfield Hospital, University of Leicester, Leicester, UK

show all

Figures & data

Table 1 Baseline clinical and bacterial characteristics of subjects with and without PPM, on routine culture and by qPCR

Download CSV Display Table

Figure 1 Scatter correlation plot of sputum neutrophils (x-axis) with pathogen-specific bacterial load (y-axis) for samples above the limit of detection (qPCR LLD >1×10⁴ copies/mL of sputum).

Notes: Data were categorized into respective sputum culture pathogens (NSG, HI, MC, SP, and SA). (A) HI. (B) MC. (C) SP. (D) SA pathogen-specific qPCR. The horizontal dashed line on the y-axis related to pathogen-specific qPCR bacterial load of 10⁶. The vertical dashed line on the x-axis related to sputum neutrophil count at 60% (neutrophilic airway inflammation).
Abbreviations: NSG, nonsignificant growth; HI, Haemophilus influenzae; LLD, lower limit of detection; MC, Moraxella catarrhalis; qPCR, quantitative real-time polymerase chain reaction; SP, Streptococcus pneumoniae; SA, Staphylococcus aureus.

Table 2 Clinical and inflammatory characteristics of COPD patients with positive qPCR categorized into absent (<10⁶), present (between 10⁶ to 10⁷), and highly present (greater than 10⁸ copies/mL)

Download CSV Display Table

Table 3 Frequency of sputum PPM detection in culture or qPCR, in 65 COPD subjects with repeated sampling over 12 months

Download CSV Display Table

Table 4 Clinical and inflammatory baseline characteristics in COPD subjects, with sputum sampling over 12 months

Download CSV Display Table

Airway bacteria measured by quantitative polymerase chain reaction and culture in patients with stable COPD: relationship with neutrophilic airway inflammation, exacerbation frequency, and lung function

Table 1 Baseline clinical and bacterial characteristics of subjects with and without PPM, on routine culture and by qPCR

Table 2 Clinical and inflammatory characteristics of COPD patients with positive qPCR categorized into absent (<10⁶), present (between 10⁶ to 10⁷), and highly present (greater than 10⁸ copies/mL)

Table 3 Frequency of sputum PPM detection in culture or qPCR, in 65 COPD subjects with repeated sampling over 12 months

Table 4 Clinical and inflammatory baseline characteristics in COPD subjects, with sputum sampling over 12 months

Information for

Open access

Opportunities

Help and information

Your download is now in progress and you may close this window

Login or register to access this feature

Airway bacteria measured by quantitative polymerase chain reaction and culture in patients with stable COPD: relationship with neutrophilic airway inflammation, exacerbation frequency, and lung function

Figures & data

Table 1 Baseline clinical and bacterial characteristics of subjects with and without PPM, on routine culture and by qPCR

Table 2 Clinical and inflammatory characteristics of COPD patients with positive qPCR categorized into absent (<106), present (between 106 to 107), and highly present (greater than 108 copies/mL)

Table 3 Frequency of sputum PPM detection in culture or qPCR, in 65 COPD subjects with repeated sampling over 12 months

Table 4 Clinical and inflammatory baseline characteristics in COPD subjects, with sputum sampling over 12 months

Related research

To cite this article:

Download citation

Information for

Open access

Opportunities

Help and information

Keep up to date

Table 2 Clinical and inflammatory characteristics of COPD patients with positive qPCR categorized into absent (<10⁶), present (between 10⁶ to 10⁷), and highly present (greater than 10⁸ copies/mL)