Sputum Cell Counts Research Articles

Nonasthmatic Eosinophilic Bronchitis: A Systematic Review of Current Treatment Options.

Nonasthmatic eosinophilic bronchitis is characterized by persistent dry or barely productive cough and bronchial eosinophilia without airway obstruction or bronchial hyperreactivity. It is primarily a chronic disease, in which some patients have clinical and pathophysiological relapses, while others progress to asthma or chronic obstructive pulmonary disease. It accounts for 5% to 30% of cases referred for chronic cough. Exposure to common inhalants and occupational sensitizers has been proposed as a possible cause of the disease, although the etiology and underlying mechanisms are uncertain. Some features are similar to those of asthma, such as airway eosinophilia, inflammatory mediator levels, and airway remodeling. Differences in airway pathophysiology, such as the location of airway inflammation and levels of IL-13 and PGE-2, have been reported. Sputum cell count is the gold standard test for diagnosis, and other biomarkers, such as exhaled nitric oxide, could support the diagnosis. A systematic review of treatments for the disease shows that while inhaled corticosteroids are the primary option, the appropriate dose, the type of corticosteroid, and the duration of treatment remain unknown. Treatment duration is inversely correlated with the relapse rate. Increased doses of inhaled corticosteroids, oral corticosteroids, and leukotriene receptor antagonists are recommended in persistent disease. Anti-IL-5 biologics could be promising in this disease. Studies that investigate biomarkers for diagnosis and prognosis are necessary, as are randomized controlled studies for second-line treatments.

8-Iso-prostaglandin F2α as a biomarker of type 2 low airway inflammation and remodeling in adult asthma

BackgroundAlthough 8-iso-prostaglandin F2a has been proposed as a potential biomarker for oxidative stress in airway diseases, its specific role in asthma remains poorly understood. ObjectiveTo evaluate the diagnostic potential of 8-iso-prostaglandin F2a in assessing airway inflammation, airway remodeling, airway hyperresponsiveness, and oxidative stress in asthma. MethodsBlood and urine concentrations of 8-iso-prostaglandin F2a were quantified using liquid chromatography–tandem mass spectrometry in 128 adults with asthma who had maintained antiasthma medications. Their correlations with clinical data, sputum cell counts, lung function parameters, and serum markers of epithelial/neutrophil activity and airway remodeling were then analyzed. ResultsThe urinary 8-iso-prostaglandin F2a concentrations were significantly higher in patients with noneosinophilic asthma than in those with eosinophilic asthma (P < .05). The area under the curve was 0.678, indicating moderate diagnostic accuracy for noneosinophilic asthma. There were significant correlations with neutrophilic inflammation markers and airway remodeling markers (all P < .05). Negative correlations were observed with forced expiratory volume in 1 second (%), forced expiratory volume in 1 second/forced vital capacity, forced expiratory flow at 25% to 75% of forced vital capacity, and serum club cell protein 16 levels (all P < .05). High 8-iso-prostaglandin F2a concentrations were also noted in obese and smoking subgroups (all P < .05). However, the serum 8-iso-prostaglandin F2a concentrations were not correlated with these asthma-related parameters. ConclusionUrinary 8-iso-prostaglandin F2a concentrations are a potential biomarker for phenotyping severe asthma, particularly noneosinophilic asthma, offering oxidative stress-induced epithelial inflammation/remodeling as an additional target in asthma management.

Relation between airway cellular and bacterial findings and severity of COPD exacerbations: A multicentric study

&lt;b&gt;Aim: &lt;/b&gt;To evaluate the relationships between sputum and bronchoalveolar lavage (BAL) cellular and bacterial findings and severity of exacerbation of chronic obstructive pulmonary disease (ECOPD).&lt;br /&gt; &lt;b&gt;Patients &amp;amp; methods: &lt;/b&gt;A cross-section study was conducted on 307 patients with ECOPD. They underwent sputum and BAL inflammatory cell count and bacterial culture.&lt;br /&gt; &lt;b&gt;Results:&lt;/b&gt; Patients with severe ECOPD have significantly higher neutrophils percentage (neut.%), lower lymphocytes percentage (lymph.%), lower eosinophils percentage (eosin.%) and higher neutrophil/lymphocyte ratio (NLR) as compared to patients with mild ECOPD. It was also shown that patients with severe ECOPD had significantly higher BAL neut.%, lower lymph.%, lower eosin.%, and higher NLR as compared to the other two subgroups. Also, patients with severe ECOPD have significantly higher frequency of cases with monomicrobial (71.30% vs. 36.10%) and polymicrobial (21.25% vs. 2.10%) growths in comparison to patients with mild ECOPD.&lt;br /&gt; &lt;b&gt;Conclusions: &lt;/b&gt;Cellular and bacterial findings in sputum and BAL are related to severity of ECOPD.

Different expression levels of interleukin-36 in asthma phenotypes

Interleukin (IL)-36 family is closely associated with inflammation and consists of IL-36α, IL-36β, IL-36γ, and IL-36Ra. The role of IL-36 in the context of asthma and asthmatic phenotypes is not well characterized. We examined the sputum IL-36 levels in patients with different asthma phenotypes in order to unravel the mechanism of IL-36 in different asthma phenotypes. Our objective was to investigate the induced sputum IL-36α, IL-36β, IL-36γ, and IL-36Ra concentrations in patients with mild asthma, and to analyze the relationship of these markers with lung function and other cytokines in patients with different asthma phenotypes. Induced sputum samples were collected from patients with mild controlled asthma (n = 62, 27 males, age 54.77 ± 15.49) and healthy non-asthmatic controls (n = 16, 10 males, age 54.25 ± 14.60). Inflammatory cell counts in sputum were determined. The concentrations of IL-36 and other cytokines in the sputum supernatant were measured by ELISA and Cytometric Bead Array. This is the first study to report the differential expression of different isoforms of IL-36 in different asthma phenotypes. IL-36α and IL-36β concentrations were significantly higher in the asthma group (P = 0.003 and 0.031), while IL-36Ra concentrations were significantly lower (P < 0.001) compared to healthy non-asthmatic controls. Sputum IL-36α and IL-36β concentrations in the neutrophilic asthma group were significantly higher than those in paucigranulocytic asthma (n = 24) and eosinophilic asthma groups (n = 23). IL-36α and IL-36β showed positive correlation with sputum neutrophils and total cell count (R = 0.689, P < 0.01; R = 0.304, P = 0.008; R = 0.689, P < 0.042; R = 0.253, P = 0.026). In conclusion, IL-36α and IL-36β may contribute to asthma airway inflammation by promoting neutrophil recruitment in airways. Our study provides insights into the inflammatory pathways of neutrophilic asthma and identifies potential therapeutic target.

Bronchiectasis with Chronic Rhinosinusitis Is Associated with Eosinophilic Airway Inflammation and Is Distinct from Asthma.

Rationale: Bronchiectasis is an airway inflammatory disease that is frequently associated with chronic rhinosinusitis (CRS). An eosinophilic endotype of bronchiectasis has recently been described, but detailed testing to differentiate eosinophilic bronchiectasis from asthma has not been performed. Objectives: This prospective observational study aimed to test the hypotheses that bronchiectasis with CRS is enriched for the eosinophilic phenotype in comparison with bronchiectasis alone and that the eosinophilic bronchiectasis phenotype exists as a separate entity from bronchiectasis associated with asthma. Methods: People with idiopathic or postinfectious bronchiectasis were assessed for concomitant CRS. We excluded people with asthma or primary ciliary dyskinesia and smokers. We assessed sputum and blood cell counts, nasal NO and fractional excreted NO, methacholine reactivity, skin allergy testing and total and specific immunoglobulin (Ig) E, cytokines in the sputum and serum, and the microbiome in the sputum and nasopharynx. Results: A total of 22 people with CRS (BE + CRS) and 17 without CRS (BE - CRS) were included. Sex, age, Reiff score, and bronchiectasis severity were similar. Median sputum eosinophil percentages were 0% (IQR, 0-1.5%) in BE - CRS and 3% (1-12%) in BE + CRS (P = 0.012). Blood eosinophil counts were predictive of sputum eosinophilia (counts ⩾3%; area under the receiver operating characteristic curve, 0.68; 95% confidence interval, 0.50-0.85). Inclusion of CRS improved the prediction of sputum eosinophilia by blood eosinophil counts (area under the receiver operating characteristic curve, 0.79; 95% confidence interval, 0.65-0.94). Methacholine tests were negative in 85.7% of patients in the BE - CRS group and 85.2% of patients in the BE + CRS group (P > 0.99). Specific IgE and skin testing were similar between the groups, but total IgE levels were increased in people with increased sputum eosinophils. Microbiome analysis demonstrated distinct microbiota in nasopharyngeal and airway samples in the BE + CRS and BE - CRS groups, without significant differences between groups. However, interactome analysis revealed altered interactomes in individuals with high sputum eosinophil counts and CRS. Conclusions: Bronchiectasis with CRS is associated with an eosinophilic airway inflammation that is distinct from asthma.

Valaciclovir for Epstein-Barr Virus Suppression in Moderate-to-Severe COPD: A Randomized Double-Blind Placebo-Controlled Trial

Epstein-Barr virus (EBV) frequently is measured at high levels in COPD using sputum quantitative polymerase chain reaction, whereas airway immunohistochemistry analysis has shown EBV detection to be common in severe disease. Is valaciclovir safe and effective for EBV suppression in COPD? The Epstein-Barr Virus Suppression in COPD (EViSCO) trial was a randomized double-blind placebo-controlled trial conducted at the Mater Hospital Belfast, Northern Ireland. Eligible patients had stable moderate-to-severe COPD and sputum EBV (measured using quantitative polymerase chain reaction) and were assigned randomly (1:1) to valaciclovir (1g tid) or matching placebo for 8weeks. The primary efficacy outcome was sputum EBV suppression (defined as≥ 90%sputum viral load reduction) at week 8. The primary safety outcome was the incidence of serious adverse reactions. Secondary outcome measures were FEV1 and drug tolerability. Exploratory outcomes included changes in quality of life, sputum cell counts, and cytokines. From November 2, 2018, through March 12, 2020, 84 patients were assigned randomly (n= 43 to valaciclovir). Eighty-one patients completed trial follow-up and were included in the intention-to-treat analysis of the primary outcome. A greater number of participants in the valaciclovir group achieved EBV suppression (n= 36 [87.8%] vsn= 17 [42.5%]; P< .001). Valaciclovir was associated with a significant reduction in sputum EBV titer compared with placebo (-90,404 copies/mL [interquartile range, -298,000 to -15,200 copies/mL] vs-3,940 copies/mL [interquartile range, -114,400 to 50,150 copies/mL]; P= .002). A statistically nonsignificant 24-mL numerical FEV1 increase was shown in the valaciclovir group (difference, -44mL [95%CI, -150 to 62mL]; P= .41). However, a reduction in sputum white cell count was noted in the valaciclovir group compared with the placebo group (difference, 2.89 [95%CI, 1.5× 106-7.4× 106]; P= .003). Valaciclovir is safe and effective for EBV suppression in COPD and may attenuate the sputum inflammatory cell infiltrate. The findings from the current study provide support for a larger trial to evaluate long-term clinical outcomes. ClinicalTrials.gov; No.: NCT03699904; URL: www. gov.

History of asthma in Canada

Asthma prevalence in Canada is high and, at least until recently, has been rising. Deaths from asthma have been gradually declining with a small but significant transient increase between about 1975 and 1995, most likely due to the inappropriate use of inhaled ß2 agonists leading to under-treatment with anti-inflammatory agents. Canada has been at the forefront of development of asthma treatments and asthma guidelines. Expressing the spectrum of asthma severity as a continuum rather than a series of steps is unique to the Canadian asthma guidelines. Other Canadian contributions include major participation in GINA, measurement of AHR, measurement of induced sputum cell counts, developments in aerosol science including large volume spacer devices, measurement of asthma quality of life and investigations into occupational asthma.

Sputum neutrophil counts in healthy subjects: relationship with age.

A threshold of ∼60% has commonly been used in asthma and COPD studies to define the presence of neutrophilic airway inflammation. This threshold is based on relatively young healthy subject datasets. However, age-related increases in sputum neutrophils have been observed previously. We used a healthy cohort, with a comparatively wider age range, to re-evaluate the age-related increase in sputum neutrophils, analysing changes by decade. We also studied the long-term repeatability of sputum neutrophil counts. Differential sputum cell count data for healthy subjects (n=121) was retrospectively analysed. Subjects with a repeated count (mean interval 4.8 years) were included in longitudinal analysis. There was a significant positive association between age and sputum neutrophil % (rho=0.24, p<0.01), with 51.2% of subjects having a sputum neutrophil count >60%. Sputum neutrophil counts increased with each decade until ∼60 years where a plateau was observed. The baseline sputum neutrophil % increased significantly at repeated sampling (p=0.02), with excellent long-term repeatability (intraclass correlation coefficient=0.80). We confirm previous reports of an age-related increase in sputum neutrophil % in healthy individuals and identified a plateau which occurs at age ∼60 years. There was an increase in sputum neutrophil % during longitudinal follow-up, indicating that age-related neutrophilia is a progressive phenomenon. These findings question the use of an unadjusted threshold, in relation to age, to identify the presence of neutrophilic airway inflammation.

To study the role of sputum cytology in patients with bronchial asthma and COPD

COPD is the major cause of morbidity and mortality across the world. In addition to this, the major factor that is contributing in this disease is smoking. This kind of problem occurs due to airflow obstruction that influences the progressive and accompanied hyper-responsiveness. The patients with Asthma and COPD overlap (ACO) have a poor quality of life and more rapid decline in lung functions and high mortality. Also, they consume a disproportionate amount of health care resources. Moreover, sputum cell counts are extensively used in the treatment of asthma and COPD. The clinical application of sputum cell count in patients with both COPD and asthma remain elusive. The study aims to study the role of sputum cytology in patients with Bronchial Asthma and COPD. It was a prospective study carried out in the Department of Pulmonary Medicine, D Y Patil Medical College, Nerul, Navimumbai, Maharashtra, India. The period of the study was from January 2020 to June 2021. The number of healthy patients recruited for the current study was 20, along with 20 asthmatic patients and 30 COPD patients. Spirometry and body plethysmography was used to measure the capacity and volume of the lungs of all the patients. One-Way Analysis of Variance (ANOVA) test was conducted for counting the differences in counts of lung function variables and sputum cells. The mean age of healthy patients was 62.78±6.1 years, asthmatic patient was 55.9±12.8 years and COPD patients was 65.8±5.2 years. According to the analysis, the specific airway's conductance for aesthetic patients was [0.60±0.04 kPa.Sec⁻¹] and for the patient who was suffering from COPD, the score was [1.82±0.19 kPa.Sec⁻¹] and the outcome for healthy patients was [1.19±0.12 kPa.Sec⁻¹].The study has found a strong relationship between sGaw and neutrophil and the neutrophil-macrophage ratio of COPD patients. According to the analysis of the study outcome, eosinophils are important for the respiratory inflammatory infiltrates in asthma patients as well as in COPD.

Validation of Sputum Biomarker Immunoassays and Cytokine Expression Profiles in COPD.

Immunoassays are commonly used to assess airway inflammation in sputum samples from chronic obstructive pulmonary disease (COPD) patients. However, assay performance and validation in this complex matrix is inconsistently reported. The aim of this study was to assess the suitability of various immunoassays for use with sputum samples, followed by use of validated immunoassays to evaluate biomarker levels in COPD patients. Assays were assessed for recombinant reference standard suitability, optimal sample dilution, standard recovery in the biological matrix and reproducibility. Validated assays were used to assess sputum supernatants in Cohort A (n = 30 COPD, n = 10 smokers, n = 10 healthy) and Cohort B (n = 81 COPD, n = 15 smokers, n = 26 healthy). Paired baseline and exacerbation samples from 14 COPD patients were assessed in cohort A, and associations with sputum cell counts and bacterial colonisation investigated in cohort B. 25/32 assays passed validation; the primary reason for validation failure was recombinant reference standard suitability and sample dilution effects. Interleukin (IL-)6 and IL-8 were significantly increased in COPD patients compared to healthy subjects and smokers for both cohorts. Tumour necrosis factor (TNF)α and IL-1β were higher in COPD compared to smokers using one immunoassay but not another, partly explained by different absolute recovery rates. IL-1β, IL-2, IL-4, IL-8, IL-17A, Granulocyte colony stimulating factor (G-CSF), Interferon (IFN-)γ, Interferon gamma induced protein (IP-)10, Macrophage inflammatory protein (MIP)-1α, MIP-1β and TNF-α levels correlated with sputum neutrophil percentage in COPD patients. IL-1β, IL-4, IL-8, G-CSF and IFN-γ levels were associated with Haemophilus influenzae colonisation in COPD patients. Current smokers had lower levels of IL-1β, IL-4, IL-8, G-CSF, IFN-γ, IP-10, Monocyte chemoattractant protein (MCP)-1, MIP-1α, MIP-1β and TNF-α. Validated immunoassays applied to sputum supernatants demonstrated differences between COPD patients and controls, the effects of current smoking and associations between Haemophilus influenzae colonisation and higher levels of selected cytokines. Immunoassay validation enabled inflammatory mediators associated with different COPD characteristics to be determined.

Astegolimab, an anti-ST2, in chronic obstructive pulmonary disease (COPD-ST2OP): a phase 2a, placebo-controlled trial

Chronic obstructive pulmonary disease (COPD) is a heterogeneous inflammatory airway disease. The epithelial-derived IL-33 and its receptor ST2 have been implicated in airway inflammation and infection. We aimed to determine whether astegolimab, a selective ST2 IgG2 monoclonal antibody, reduces exacerbations in COPD. COPD-ST2OP was a single-centre, randomised, double-blinded, placebo-controlled phase 2a trial in moderate-to-very severe COPD. Participants were randomly assigned (1:1) with a web-based system to received 490 mg subcutaneous astegolimab or subcutaneous placebo, every 4 weeks for 44 weeks. The primary endpoint was exacerbation rate assessed for 48 weeks assessed with a negative binomial count model in the intention-to-treat population, with prespecified subgroup analysis by baseline blood eosinophil count. The model was the number of exacerbations over the 48-week treatment period, with treatment group as a covariate. Safety was assessed in the whole study population until week 60. Secondary endpoints included Saint George's Respiratory Questionnaire for COPD (SGRQ-C), FEV1, and blood and sputum cell counts. The trial was registered with ClinicalTrials.gov, NCT03615040. The exacerbation rate at 48 weeks in the intention-to-treat analysis was not significantly different between the astegolimab group (2·18 [95% CI 1·59 to 2·78]) and the placebo group (2·81 [2·05 to 3·58]; rate ratio 0·78 [95% CI 0·53 to 1·14]; p=0·19]). In the prespecified analysis stratifying patients by blood eosinophil count, patients with 170 or fewer cells per μL had 0·69 exacerbations (0·39 to 1·21), whereas those with more than 170 cells per μL had 0·83 exacerbations (0·49 to 1·40). For the secondary outcomes, the mean difference between the SGRQ-C in the astegolimab group versus placebo group was -3·3 (95% CI -6·4 to -0·2; p=0·039), and mean difference in FEV1 between the two groups was 40 mL (-10 to 90; p=0·094). The difference in geometric mean ratios between the two groups for blood eosinophil counts was 0·59 (95% CI 0·51 to 0·69; p<0·001) and 0·25 (0·19 to 0·33; p<0·001) for sputum eosinophil counts. Incidence of treatment-emergent adverse events was similar between groups. In patients with moderate-to-very severe COPD, astegolimab did not significantly reduce exacerbation rate, but did improve health status compared with placebo. Funded by Genentech and National Institute for Health Research Biomedical Research Centres.

Assessment of airway inflammation and disease burden in moderate to severe asthmatic smokers

BACKGROUND: Conflicting results have been found among studies assessing the effect of smoking on airway inflammation among asthmatic subjects. OBJECTIVE: We sought to compare the inflammatory and clinical characteristics of active smokers and nonsmokers with uncontrolled moderate-to-severe asthma. Methods: We conducted a cross-sectional study comparing active-smoker and nonsmoker subjects with uncontrolled moderate-to-severe asthma. Sociodemographic and clinical data were collected. FeNO levels and spirometry were measured. We obtained sputum and blood cell counts and measured the cotinine level. The clinical data were linked to 3 Québec administrative databases. RESULTS: A total of 40 active smokers and 39 nonsmokers were included. Uncontrolled asthmatic smokers and nonsmokers had the same clinical characteristics. Although, blood eosinophil counts were similar between groups, the number of subjects with a high sputum eosinophil count (> 10%) was higher in nonsmokers. Asthmatic smokers had lower levels of FeNO than nonsmoker asthmatics. The nonsmoker group showed a higher number of total asthma exacerbations (1.9 ± 0.7) than the smoker group (1.0 ± 1.2) (p < 0.01) in the year preceding their assessment. The annual costs related to asthma care tended to be higher in uncontrolled asthmatic nonsmokers (352.05 ± 813.45CAD) than in smokers (263.38 ± 684.00CAD), whereas the annual cost for health care of all causes tended to be lower in nonsmokers (1617.57 ± 1736.53 CAD) than in smokers (2575.07 ± 3453.30 CAD). INTERPRETATION: The clinical characteristics of uncontrolled moderate-to-severe active asthmatic smokers and nonsmokers were similar. Although the FeNO levels were profoundly affected by smoking, the impact of smoking on airway eosinophilic inflammation appeared marginal. CLINICAL TRIAL REGISTRATION: NCT02833727

Longitudinal Impact of Sputum Inflammatory Phenotypes on Small Airway Dysfunction and Disease Outcomes in Asthma

Little is known about the relationship between airway inflammatory phenotypes and some important asthma features such as small airway dysfunction (SAD). To describe the longitudinal impact of airway inflammatory phenotypes on SAD and asthma outcomes. We measured eosinophil and neutrophil counts in induced sputum at baseline and 1 year later to stratify 197 adult patients with asthma into 4 inflammatory phenotypes. We conducted a comprehensive assessment of lung function using spirometry, body plethysmography, impulse oscillometry, and inert gas single and multiple breath washouts. We compared lung function, asthma severity, exacerbation frequency, and symptom control between the phenotypes. We studied the longitudinal impact of persistent sputum inflammatory phenotypes and the change of sputum cell counts on lung function. Patients were stratified into eosinophilic (23%, n=45), neutrophilic (33%, n= 62), mixed granulocytic (22%, n= 43), and paucigranulocytic (24%, n= 47) phenotypes. Patients with eosinophilic and mixed granulocytic asthma had higher rates of airflow obstruction and severe exacerbation as well as poorer symptom control than patients with paucigranulocytic asthma. All SAD measures were worse in patients with eosinophilic and mixed asthma than in those with paucigranulocytic asthma (all P values <.05). Eosinophilic asthma also indicated worse distal airflow obstruction, increased ventilation inhomogeneity (all P values <.05), and higher tendency for severe exacerbation (P= .07) than neutrophilic asthma. Longitudinally, persistent mixed granulocytic asthma was associated with the worst follow-up measures of SAD compared with persistent neutrophilic, persistent paucigranulocytic, or nonpersistent asthma phenotypes. In patients with stable forced expiratory volume in 1 second (FEV1), the mean increase in small airway resistance (R5-20) was greater in patients with persistent mixed granulocytic asthma (+103%) than in patients with persistent neutrophilic (+26%), P= .040, or persistent paucigranulocytic asthma (-41%), P= .028. Multivariate models adjusted for confounders and treatment with inhaled or oral corticosteroids or antieosinophilic biologics indicated that the change of sputum eosinophil rather than neutrophil counts is an independent predictor for the longitudinal change in FEV1, forced expiratory flow at 25% to 75% of forced vital capacity, specific effective airway resistance, residual lung volume, and lung clearance index. In asthma, airway eosinophilic inflammation is the main driver of lung function impairment and poor disease outcomes, which might also be aggravated by the coexistence of airway neutrophilia to confer a severe mixed granulocytic asthma phenotype. Persistent airway eosinophilia might be associated with dynamic SAD even in patients with stable FEV1.

Characteristics of different asthma phenotypes associated with cough: a prospective, multicenter survey in China

BackgroundAsthma is a heterogeneous disease with variable symptoms, which presents with cough either as the sole or predominant symptom with or without wheezing. We compared the clinical and pathophysiological characteristics of cough predominant asthma (CPA), cough variant asthma (CVA) and classic asthma (CA) in order to determine any differential phenotypic traits.MethodsIn 20 clinics across China, a total of 2088 patients were finally recruited, including 327 CVA, 1041 CPA and 720 CA patients. We recorded cough and wheezing visual analogue scale, Leicester cough questionnaire (LCQ) and asthma control test scores. Fractional exhaled nitric oxide (FeNO), induced sputum cell counts, and capsaicin cough challenge were also measured and compared.ResultsCPA patients more frequently presented with cough as the initial symptom, and laryngeal symptoms (p < 0.001), had less symptoms related with rhinitis/sinusitis and gastroesophageal reflux (p < 0.05) than CA patients. Comorbidities including rhinitis and gastroesophageal reflux were similar, while the proportion of COPD and bronchiectasis was higher in CA patients. There were no differences in FeNO levels, sputum eosinophil and neutrophil counts, FEV1 (%pred) decreased from CVA to CPA to CA patients (p < 0.001). Cough sensitivity was higher in CVA and CPA compared to CA (p < 0.001), and was positively correlated with LCQ scores.ConclusionsCVA, CPA and CA can be distinguished by the presence of laryngeal symptoms, cough sensitivity and airflow obstruction. Asthma-associated chronic cough was not associated with airway inflammation or comorbidities in our cohort.Trial registration The Chinese Clinical Trial Registration Center, ChiCTR-POC-17011646, 13 June 2017

Paucigranulocytic asthma: Do sputum macrophages matter?

Background: Although paucigranulocytic asthma (PGA) is the most common phenotype of stable asthma, its features have not been adequately studied. In this study, we aimed to display the characteristics of PGA. Method: A total of 116 non-smoking adult patients with asthma (80% women; mean ± standard deviation age, 39 ± 12.9 years) admitted to three tertiary centers were included. Their demographic and clinical features, allergy status, biochemical results, scores of Asthma Control Test (ACT), spirometry, and exhaled nitric oxide (FeNO) measurements were obtained. Induced sputum cytometry was performed. Results: Four phenotypes, according to induced sputum cell counts, were detected: eosinophilic asthma (EA) (22.4%), mixed granulocytic asthma (MGA) (6.9%), neutrophilic (NA) (7.8%), and PGA (62.9%). In the sputum, macrophages were higher in the PGA group compared with the other groups (PGA versus NA and PGA versus MGA, p < 0.001; and PGA versus EA, p =0 .030). The atopy rate between phenotypes was the same. Although the forced expiratory volume in the first second of expiration (FEV1) was similar in four groups, the ratio of FEV1 to the forced vital capacity ratio was higher (p = 0.013) and FEV1 reversibility was lower in the patients with PGA than the corresponding values in other phenotypes (p = 0.015). Low reversibility was comparable both in patients with PGA who were inhaled corticosteroid (ICS) naive and in patients on ICS treatment. Although insignificant, the FeNO values and blood eosinophil counts were higher in the MGA and EA groups, whereas these were the lowest in the PGA group. The uncontrolled asthma ratio was low in PGA (16%), whereas it was 11% for NA, 25% for MG, and 23% in EA. Conclusion: Macrophages are predominant in sputum of patients with PGA. Besides a lower uncontrolled asthma ratio, lower FEV1 reversibility is a prominent characteristic of this phenotype.

Cough hypersensitivity in patients with metabolic syndrome: a clinical finding and its possible mechanisms

PurposeTo investigate the changes of cough sensitivity in patients with metabolic syndrome and its possible mechanisms.MethodA total of 29 metabolic syndrome (MetS) patients with OSAHS (group-1), 22 MetS patients without OSAHS (group-2), and 25 healthy controls (group-3) were included. All participants underwent a routine physical examination and completed the gastroesophageal reflux disease questionnaire (GerdQ), and the inflammatory mediator profile were determined. The cough threshold for capsaicin, induced sputum cell count and cell classification, and inflammatory mediators in induced sputum supernatants were compared. The correlation between capsaicin cough sensitivity and various indicators in the MetS population was analyzed.ResultsThe minimum concentration of inhaled capsaicin needed to induce ≥ 5 coughs (C5) was significantly different among three groups (H = 14.393, P = 0.001) and lower for group-1 and group-2 than it for group-3 (P = 0.002, P = 0.005). The percentage of neutrophils in induced sputum and the concentrations of calcitonin gene-related peptide (CGRP), substance P (SP), and interleukin 8 (IL-8) in the sputum supernatant of group-1 and group-2 were significantly higher than those of group-3. Besides, the pepsin concentrations were significantly different among the 3 groups (F = 129.362, P < 0.001), which significantly was highest in group-1 (P < 0.001) and lowest in group-3 (P < 0.001). Triglycerides, AHI, pepsin concentration and BMI were risk factors of increased capsaicin cough sensitivity.ConclusionIncreased capsaicin cough sensitivity in MetS patients is closely related to sleep apnea and gastroesophageal reflux. For patients in MetS patients without OSAHS, gastroesophageal reflux is an important factor for increased capsaicin cough sensitivity. Airway inflammation, especially airway neurogenic inflammation, may also play a role in the pathogenesis of increased capsaicin cough sensitivity.Trial registration The protocol was registered in the Chinese Clinical Trials Register (http://www.chictr.org.cn/) (ChiCTR1800014768). Written informed consent was obtained from all participants before enrollment.

Association of the CFTR gene with asthma and airway mucus hypersecretion.

Asthma with airway mucus hypersecretion is an inadequately characterized variant of asthma. While several studies have reported that hypersecreting patients may carry genetic variants in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, many of those studies have been questioned for their numerous limitations and contradictory results. (1) To determine the presence of genetic variants of the CFTR gene in patients with asthma with and without airway mucus hypersecretion. (2) To identify the clinical, inflammatory and functional characteristics of the asthma phenotype with airway mucus hypersecretion. Comparative multicentre cross-sectional descriptive study that included 100 patients with asthma (39 hypersecretors and 61 non-hypersecretors). Asthmatic hypersecretion was defined as the presence of cough productive of sputum on most days for at least 3 months in 2 successive years. The patients were tested for fractional exhaled nitric oxide, spirometry, induced sputum cell count, total immunoglobulin E (IgE), peripheral blood eosinophil count, C-reactive protein, blood fibrinogen and blood albumin and underwent a skin prick test. Asthma control and quality of life were assessed by the Asthma Control Test and Mini Asthma Quality of Life questionnaires, respectively. Blood DNA samples were collected from the patients and next-generation sequencing using a MiSeq sequencer and the Illumina platform was used for the CFTR gene analysis. Genetic differences were observed in the c.1680-870T>A polymorphism of the CFTR gene, significantly more evident in hypersecretors than in non-hypersecretors: 78.94% vs. 59.32% in the majority allele and 21.05% vs. 40.67% in the minority allele (p = 0.036). Clinically, asthma hypersecretors compared to non-hypersecretors were older (57.4 years vs. 49.4 years; p = 0.004); had greater asthma severity (58.9% vs. 23.7%; p = 0.005); experienced greater airway obstruction (FEV1/FVC% 64.3 vs. 69.5; p = 0.041); had poorer asthma control (60% vs. 29%; p = 0.021); had lower IgE levels (126.4 IU/mL vs. 407.6 IU/mL; p = 0.003); and were less likely to have a positive prick test (37.5% vs. 68.85%; p = 0.011). The results suggest that patients with asthma and with mucus hypersecretion (1) may have a different phenotype and disease mechanism produced by an intronic polymorphism in the CFTR gene (NM_000492.3:c.1680-870T>A), and (2) may have a poorer clinical outcome characterized by severe disease and poorer asthma control with a non-allergic inflammatory phenotype.

Characteristics of inflammatory phenotypes among patients with asthma: relationships of blood count parameters with sputum cellular phenotypes

BackgroundThere is a need to identify the asthma inflammatory phenotypes of patients to facilitate personalized asthma treatment. Sputum induction is time-consuming and requires expert clinical technique. This study aimed to assess the distribution and characteristics of asthma inflammatory phenotypes in Jilin Province, China; it also aimed to identify an easier method for characterization of an asthma phenotype, rather than sputum cellular analysis.MethodsIn this study, 232 asthma patients underwent sputum induction following clinical assessment and blood collection. Inflammatory cell counts in sputum were used to classify asthma inflammatory phenotypes. Receiver operating characteristic curve and Spearman correlation coefficient analyses were used to identify correlations between clinical parameters.ResultsAmong the included patients, there had 52.1% paucigranulocytic, 38.4% eosinophilic, 4.3% neutrophilic, and 5.2% mixed granulocytic asthma phenotypes, respectively. In total, 129 (55.6%) patients had asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO); these patients had higher proportion of smokers, higher sputum neutrophil count, worse lung function, and worse asthma control, compared with patients who had asthma alone (p < 0.05). Sputum eosinophil/neutrophil counts were positively correlated with blood eosinophil/neutrophil counts (p < 0.01). To identify the presence of sputum eosinophil proportion ≥ 3%, optimal cut-off values for blood eosinophil count and fractional exhaled nitric oxide (FeNO) were 0.2 × 109/L and 30.25 ppd (area under the curve (AUC) = 0.744; AUC = 0.653, p < 0.001). AUCs did not significantly differ between FeNO and blood eosinophil count (p = 0.162), but both exhibited poor specificity (57% and 49%, respectively). To identify the presence of sputum neutrophil proportion ≥ 61%, the optimal cut-off value for blood neutrophil proportion was 69.3% (AUC = 0.691, p = 0.0003); however, this exhibited poor sensitivity (50%).ConclusionsPaucigranulocytic asthma was the most common phenotype, followed by eosinophilic asthma. Higher proportion of smokers, poor patient compliance, insufficient treatment, and poor asthma control may have been the main causes of high ACO proportion among patients in this study. Blood eosinophil/neutrophil counts exhibited poor specificity and sensitivity for prediction of airway eosinophilic/neutrophilic inflammation.

Elevated serum calprotectin (S100A8/A9) in patients with severe asthma

Objective Asthma is a heterogeneous disease consisting of several inflammatory phenotypes of which neutrophilic asthma is associated with poorer responses to classic therapies, namely (inhaled) corticosteroids. The development of targeted therapies requires the identification of biomarkers to distinguish these phenotypes. Currently, we lack validated biomarkers for non-eosinophilic asthma. The aim of this study is to examine serum calprotectin (SC) in asthmatics and its potential as biomarker for neutrophilic asthma. Methods Hundred-seventeen severe asthmatics were referred for sputum induction and data were obtained from their medical records. To evaluate the association between SC and asthma phenotypes, patients were divided into subgroups based on sputum cell count (3% eosinophils and 61% neutrophils). Additionally, SC levels of asthmatics were compared with these of patients with chronic obstructive pulmonary disease, non-cystic fibrosis bronchiectasis and healthy controls. Results Asthmatics (n = 45) had significantly higher levels of SC than healthy controls. No significant differences were found between the different asthma phenotypes and in comparison with COPD patients. SC was significantly higher in asthmatics with a lower FEV1/FVC ratio (<70) and non-significantly elevated SC levels were seen in asthmatics with frequent exacerbations (>2 in the last year). Conclusion In conclusion, there was no difference in SC levels between the different inflammatory subtypes in asthmatics. Nevertheless, severe asthmatics seemed to have higher SC levels suggesting that SC may be a marker of disease severity rather than a marker for specific inflammatory subtypes in asthmatics. Further research in larger cohorts is necessary to validate SC as biomarker in severe asthmatics.

Multi-omics links IL-6 trans-signalling with neutrophil extracellular trap formation and Haemophilus infection in COPD.

Interleukin (IL)-6 trans-signalling (IL-6TS) is emerging as a pathogenic mechanism in chronic respiratory diseases; however, the drivers of IL-6TS in the airways and the phenotypic characteristic of patients with increased IL-6TS pathway activation remain poorly understood. Our aim was to identify and characterise COPD patients with increased airway IL-6TS and to elucidate the biological drivers of IL-6TS pathway activation. We used an IL-6TS-specific sputum biomarker profile (soluble IL-6 receptor (sIL-6R), IL-6, IL-1β, IL-8, macrophage inflammatory protein-1β) to stratify sputum data from patients with COPD (n=74; Biomarkers to Target Antibiotic and Systemic Corticosteroid Therapy in COPD Exacerbation (BEAT-COPD)) by hierarchical clustering. The IL-6TS signature was related to clinical characteristics and sputum microbiome profiles. The induction of neutrophil extracellular trap formation (NETosis) and IL-6TS by Haemophilus influenzae were studied in human neutrophils. Hierarchical clustering revealed an IL-6TS-high subset (n=24) of COPD patients, who shared phenotypic traits with an IL-6TS-high subset previously identified in asthma. The subset was characterised by increased sputum cell counts (p=0.0001), persistent sputum neutrophilia (p=0.0004), reduced quality of life (Chronic Respiratory Questionnaire total score; p=0.008), and increased levels of pro-inflammatory mediators and matrix metalloproteinases in sputum. IL-6TS-high COPD patients showed an increase in Proteobacteria, with Haemophilus as the dominating genus. NETosis induced by H. influenzae was identified as a potential mechanism for increased sIL-6R levels. This was supported by a significant positive correlation between sIL-6R and NETosis markers in bronchoalveolar lavage fluid from COPD patients. IL-6TS pathway activation due to chronic colonisation with Haemophilus may be an important disease driver in a subset of COPD patients.