Investigating the role of pentraxin 3 as a biomarker for bacterial infection in subjects with COPD

Figures & data

Table 1 Proportion of subjects below and above the cutoff of 10⁵ CFU/mL that had a negative or positive microbiology results at stable state

Culture results	<10^5 (n=8)	>10^5 (n=65)
No significant growth	5	34
Positive pathogen culture (Haemophilus influenzae, Streptococcus pneumoniae, Moraxella catarrhalis, Staphylococcus aureus, Pseudomonas aeruginosa)	3	31

Abbreviation: CFU, colony-forming units.

Table 2 Baseline characteristics of the 142 COPD subjects included in this analysis of pentraxin 3 levels

Subjects, n	142
Male (%)	102 (72)
Age (years)a	69 (45–88)
Smokers, n (%)	49 (34)
Ex-smokers, n (%)	88 (62)
Pack year history (units)a	52 (10–159)
GOLD 1 (%)	4 (3)
GOLD 2 (%)	56 (39)
GOLD 3 (%)	50 (35)
GOLD 4 (%)	32 (23)
Post-bronchodilator FEV1 (L)	1.30 (0.51)
Post-bronchodilator FEV1 (%)	50 (19)
FEV1/FVC ratio (%)	25 (25)
SGRQ, total score (units)	53.86 (17.59)
MRC (units)c	3.00 (2.00–4.00)
CRQ (units)	4.05 (1.14)
VAS total score (mm)	154.8 (77.56)
Inhaled corticosteroids treatment (%)	128 (90)
Long-acting beta agonist treatment (%)	118 (83)
Sputum neutrophils (%)	71 (22)
Total sputum neutrophil count (×10^3/mg)b	2.50 (1.92–3.25)
Sputum eosinophils (%)b	1.16 (0.92–1.47)
Total sputum eosinophil count (×10^3/mg)b	0.15 (0.10–0.19)
Colony-forming units/mLb (×10^7)	1.12 (0.72–1.74)
Bacterial load in sputum plugb (×10^8)	2.64 (1.76–3.91)

Notes: Unless indicated, all data are presented as mean and standard deviation in brackets. GOLD, Global Initiative for Chronic Obstructive Lung Disease individuals grouped (1–4) by severity of disease; SGRQ, scores ranging from 0 to 100 with higher score indicating worse health status (total score on domains of impact, symptoms, and activity); CRQ, scores range between 1 and 7 with higher score representing better health quality; VAS, performed on 100 mm line from “no symptoms” to “worst symptoms”, higher scores represent worse symptoms (total score addition of measured domains: cough, dyspnea, sputum production, and sputum purulence).

a Mean (range).

b Geometric mean and 95% confidence intervals.

c Median (interquartile range).

Abbreviations: CRQ, chronic respiratory disease questionnaire; FEV₁, forced expiratory volume in 1 second; FVC, forced vital capacity; MRC, medical research council; SGRQ, St George’s respiratory questionnaire; VAS, visual analog scale.

Figure 1 Correlations between PTX3 and (A) TCC in sputum; (B) absolute neutrophil count in sputum; (C) CFU/mL (C); and (D) bacterial load measured by 16S quantitative polymerase chain reaction.

Abbreviations: CFU, colony forming units; PTX3, pentraxin 3; TCC, total cell count.

Figure 2 PTX3 levels from 10 subjects over three stable visits.

Note: Mean 95% CI.
Abbreviations: CI, confidence interval; PTX3, pentraxin 3.

Table 3 Difference in culture growth between subjects that saw an increase in PTX3 levels compared with those that saw a decrease from stable to exacerbation state

Microbiology result	Increase in PTX3 (n=57)	No increase (n=38)
Haemophilus influenzae	16 (28)	5 (13)
Moraxella catarrhalis	5 (8)	1 (3)
Streptococcus pneumoniae	7 (12)	1 (3)
Staphylococcus aureus	0 (0)	0 (0)
Pseudomonas aeruginosa	1 (2)	2 (6)
No significant growth	28 (49)	29 (76)

Note: Data presented as n (%).

Abbreviation: PTX3, pentraxin 3.

Figure 3 PTX3 levels when divided according to the presence of a virus or bacterial infection.

Note: Mean 95% CI.

Abbreviations: CI, confidence interval; PTX3, pentraxin 3.

Figure 4 PTX3 levels in 11 paired sputum samples at stable, exacerbation, and 2 weeks post-exacerbation treatment.

Abbreviation: PTX3, pentraxin 3.