Total and specific immunoglobulin E in induced sputum in allergic and non-allergic asthma.

BACKGROUND: Most patients with nonallergic asthma have normal serum immunoglobulin E (IgE) levels. Recent reports suggest that total and aeroallergen-specific IgE levels in induced sputum may be higher in nonallergic asthmatics than in healthy controls. Our objective is to compare total and dust-mite specific (Der p 1) IgE levels in induced sputum in allergic and nonallergic asthmatics and healthy controls. METHODS: Total and Der p 1-specific IgE were measured in induced sputum (ImmunoCAP immunoassay) from 56 age- and sex-matched asthmatics (21 allergic, 35 nonallergic) and 9 healthy controls. Allergic asthma was defined as asthma with a positive prick test and/or clinically-significant Der p 1-specific serum IgE levels. RESULTS: Patients with allergic asthma presented significantly higher total and Der p 1-specific serum IgE levels. There were no significant between-group differences in total sputum IgE. However, Der p 1-specific sputum IgE levels were significantly higher (p = 0.000) in the allergic asthmatics, but without differences between the controls and nonallergic asthmatics. Serum and sputum IgE levels were significantly correlated, both for total IgE (rho = 0.498; p = 0.000) and Der p 1-specific IgE (rho, 0.621; p = 0001). CONCLUSIONS: Total IgE levels measured in serum and induced sputum are significantly correlated. No significant differences were found between the differents groups in total sputum IgE. Nevertheless, the levels of Der p 1-specific sputum IgE levels were significantly higher in the allergic asthmatics, but without differences between the controls and nonallergic asthmatics. Probably due to the lack of sensitivity of the test used, but with the growing evidence for local allergic reactions better methods are need to explore its presence. The Clinical Trials Identifier for this project is NCT03640936.

Asthma with bronchial hypersecretion: expression of mucins and toll-like receptors in sputum and blood.

Asthma with bronchial hypersecretion is a type of asthma that is poorly studied. Its pathogenesis is not well understood, but is probably related to innate impaired immunity, particularly with toll-like receptors (TLRs) and secretory mucins (MUC). OBJECTIVES: 1) Define the clinical and inflammatory phenotype of asthma with bronchial hypersecretion of mucus. 2) Compare the type of mucin present in induced sputum (IS) of patients with and without bronchial hypersecretion. 3) Determine the expression of TLRs in IS and blood of asthmatics with and without bronchial hypersecretion. MATERIALS AND METHODS: Cross-sectional study which included 43 non-smoking asthmatic patients without bronchiectasis, 19 with bronchiectasis, and 24 without bronchial hypersecretion. All patients underwent the following: IS, spirometry, fractional exhaled nitric oxide, prick test, total immunoglobulin E (IgE), and blood albumin. Analysis of mucins was determined by ELISA and expression of TLR2 and TLR4 by flow cytometry. The level of asthma control was determined by the Asthma Control Test (ACT) questionnaire and quality of life was assessed by the reduced version of the Asthma Quality of Life Questionnaire (mini-AQLQ). RESULTS: Asthmatics with bronchial hypersecretion were significantly older (62.6 years vs 48.5 years; p=0.02); had greater severity (persistent severe asthma 94.7% vs 29.2%; p=0.000); a higher proportion of nasal polyposis (36.8% vs 8.3%; p=0.022); less control of asthma (73.7% vs 8.3%; p=0,000); a higher proportion of asthma with negative prick test (68.4% vs 16.6%; p=0.001), and lower levels of IgE (113.4 IU/mL vs 448 IU/mL; p=0.007), compared with asthmatics without bronchial hypersecretion. Significant differences were observed neither in the expression of TLRs 2 and 4 in inflammatory cells of IS or peripheral blood, nor in the expression of mucins between both groups. CONCLUSION: Asthma patients with bronchial hypersecretion have more severe and uncontrolled disease, with poor quality of life as well as a non-allergic inflammatory phenotype. Within the mechanisms involving these differences, it does not appear that mucins and TLRs play an important role.

Utilidad del esputo inducido en la práctica clínica habitual / Utility of Induced Sputum in Routine Clinical Practice

Objetivos: Determinar la utilidad general y específica (diagnóstica y/o terapéutica) del recuento de las células inflamatorias (RCI) del esputo inducido (EI) en situación de asistencia clínica real. Métodos: Estudio retrospectivo que incluyó a los 171 pacientes que durante un año se les recogió un EI para determinar su RCI en un servicio de Neumología de un hospital de referencia. Observadores independientes al equipo médico habitual establecieron si la información proporcionada por el RCI del EI fue útil en la toma de decisiones diagnósticas y terapéuticas. Resultados: Las causas más frecuentes que motivaron la solicitud del RCI del EI fueron: asma 103 (59,20%); asma de control difícil 34 (19,54%); tos crónica 19 (10,9%), y reflujo gastroesofágico 15 (8,6%). En 115 (67,3%) pacientes el RCI del EI resultó clínicamente útil (valoración general); en 98 (57,3%) proporcionó información diagnóstica, y en 85 (49,7%), información terapéutica relevante. En el asma, asma de control difícil, tos crónica y reflujo gastroesofágico fue útil en el 71,8, el 67,6, el 47,4 y el 60%, respectivamente. Conclusiones: La información proporcionada por el RCI del EI resulta de gran utilidad en la práctica clínica, particularmente en el asma y la tos crónica. Estos resultados podrían proporcionar argumentos para recomendar la incorporación de la técnica en los servicios de Neumología de referencia y en las unidades de excelencia de asma)

Objective: To determine the general and specific utility in diagnosis and/or treatment of induced sputum (IS) inflammatory cell counts in routine clinical practice. Methods: Retrospective study of 171 patients referred for clinical sputum induction over a 1-year period in the pulmonology department of a referral hospital. Independent observers established whether the information provided by IS inflammatory cell count was useful for making diagnostic and therapeutic decisions. Results: The most frequent reasons for determination of IS inflammatory cell count were: asthma 103 (59.20%); uncontrolled asthma 34 (19.54%); chronic cough 19 (10.9%), and gastroesophageal reflux 15 (8.6%). In 115 patients (67.3%) it was generally useful for diagnosis and/or treatment; in 98 patients (57.3%) it provided diagnostic information and in 85 patients (49.7%) it assisted in therapeutic decision-making. In asthma, uncontrolled asthma, chronic cough and gastroesophageal reflux, the results were useful in 71.8%, 67.6%, 47.4% and 60%, respectively. Conclusion: The information provided by IS inflammatory cell count is extremely useful in clinical practice, especially in asthma and chronic cough. These results may justify the inclusion of the IS technique in pulmonology departments and asthma units of referral centers

Expression of toll-like receptors 2 and 4 in subjects with asthma by total serum IgE level.

BACKGROUND: Emerging data suggest that innate immunity may play a role in asthma, particularly the toll-like receptors (TLRs). Some studies pointed to an involvement of TLRs 2 and 4 in the pathogenesis of allergic asthma, and other studies related TLRs to IgE. However, there are not any studies that have comprehensively evaluated the expression of TLRs 2 and 4 in inflammatory cells, in peripheral blood and induced sputum specimens from asthmatic patients, according to their total serum IgE. METHODS: We studied 44 asthmatic patients (15 with high total serum IgE and 29 with normal total serum IgE). On a single visit, all patients underwent: induced sputum, pulmonary function tests, determination of exhaled nitric oxide fraction, venipuncture for blood analysis and skin prick allergy tests. The induced sputum cellularity was analyzed by flow cytometry, where expression of TLRs 2 and 4 was studied using fluorochrome-conjugated monoclonal antibodies. RESULTS: Asthmatic patients with high total serum IgE showed, a higher percentage of macrophages expressing TLR4 (42.99 % ± 22.49) versus asthmatic patients with normal total serum IgE (28.84 % ± 15.16) (P = 0.048). Furthermore, we observed a correlation (but weak) between the percentage of macrophages expressing TLR4 in induced sputum and the total serum IgE level (R = 0.314; P = 0.040). CONCLUSION: Asthmatic subjects with high total serum IgE show increased macrophage expression of TLR4 in induced sputum. This outcome may result from a link between innate immunity and IgE-mediated, adaptive immune responses in asthma, and point to TLR4 as a potential therapeutic target.

Airway Mucin 2 Is Decreased in Patients with Severe Chronic Obstructive Pulmonary Disease with Bacterial Colonization.

RATIONALE: Mucins are essential for airway defense against bacteria. We hypothesized that abnormal secreted airway mucin levels would be associated with bacterial colonization in patients with severe chronic obstructive pulmonary disease (COPD) Objectives: To investigate the relationship between mucin levels and the presence of potentially pathogenic micro-organisms in the airways of stable patients with severe COPD Methods: Clinically stable patients with severe COPD were examined prospectively. All patients underwent a computerized tomography scan, lung function tests, induced sputum collection, and bronchoscopy with bronchoalveolar lavage (BAL) and protected specimen brush. Patients with bronchiectasis were excluded. Secreted mucins (MUC2, MUC5AC, and MUC5B) and inflammatory markers were assessed in BAL and sputum by ELISA. MEASUREMENTS AND MAIN RESULTS: We enrolled 45 patients, with mean age (±SD) of 67 (±8) years and mean FEV1 of 41 (±10) % predicted. A total of 31% (n = 14) of patients had potentially pathogenic micro-organisms in quantitative bacterial cultures of samples obtained by protected specimen brush. Patients with COPD with positive cultures had lower levels of MUC2 both in BAL (P = 0.02) and in sputum (P = 0.01). No differences in MUC5B or MUC5AC levels were observed among the groups. Lower MUC2 levels were correlated with lower FEV1 (r = 0.32, P = 0.04) and higher sputum IL-6 (r = -0.40, P = 0.01). CONCLUSIONS: Airway MUC2 levels are decreased in patients with severe COPD colonized by potentially pathogenic micro-organisms. These findings may indicate one of the mechanisms underlying airway colonization in patients with severe COPD. Clinical trial registered with www.clinicaltrials.gov (NCT01976117).

Variabilidad del fenotipo inflamatorio del asma en el esputo inducido. Frecuencia y causas / Variability in Asthma Inflammatory Phenotype in Induced Sputum. Frequency and Causes

Introducción: Estudios recientes han constatado variabilidad del fenotipo inflamatorio del asma en el recuento de las células inflamatorias del esputo inducido (EI). El objetivo del presente estudio fue determinar la frecuencia y los factores que condicionan la variabilidad del fenotipo inflamatorio del EI. Métodos: Estudio observacional retrospectivo que incluyó 61 pacientes asmáticos a los que se les practicó un mínimo de dos EI en un período de 5 años. Los pacientes fueron clasificados según su fenotipo inflamatorio y posteriormente agrupados según la variabilidad del fenotipo (eosinofílicos persistentes, no eosinofílicos persistentes y eosinofílicos intermitentes). De todos los casos incluidos se recogieron datos demográficos y clínico-funcionales, así mismo se valoró los factores que pudiesen influir en la variabilidad del EI. Resultados: De los 61 pacientes, 31 (50,8%) presentaron un cambio del fenotipo inflamatorio inicial. De estos, 16 (51,6%) eran eosinofílicos, 5 (16,1%) neutrofílicos; 1 (3,2%) mixto y 9 (29,1%) paucigranulocíticos. Según la variabilidad, 18 pacientes (29,5%) se clasificaron como eosinofílicos persistentes, 17 (27,9%) no eosinofílicos persistentes y 26 (42,6%) eosinofílicos intermitentes. El tabaquismo y una exacerbación asmática reciente se asociaron significativamente con mayor riesgo de variabilidad del fenotipo inflamatorio del EI (OR = 6,44; p = 0,013; IC95% = 1,49-27,80 y OR = 5,84; p = 0,022; IC95%=1,29-26,37, respectivamente). Conclusión: La mitad de los pacientes asmáticos modifican el fenotipo inflamatorio del EI, predominando los de fenotipo eosinofílico. Esta variabilidad se asocia al tabaquismo y a una exacerbación asmática reciente. Los datos sugieren que estos factores podrían influir en la determinación del fenotipo inflamatorio del EI en la práctica clínica habitual

Introduction: Recent studies have found variability in asthma inflammatory phenotypes determined by the inflammatory cells in induced sputum (IS). The aim of this study was to determine the frequency and factors affecting inflammatory phenotype variability in IS. Methods: Retrospective observational study that included 61 asthmatic patients who underwent at least two IS tests over a period of 5 years. They were classified according to their baseline inflammatory phenotype and subsequently grouped according to phenotype variability (persistent eosinophilic, persistent non-eosinophilic and intermittent eosinophilic). Demographic, clinical and functional data and factors potentially influencing IS variability were collected in all cases. Results: Of the 61 patients, 31 (50.8%) had a change with respect to baseline inflammatory phenotype. Of these, 16 (51.6%) were eosinophilic, 5 (16.1%) neutrophilic, 1 (3.2%) mixed and 9 (29.1%) paucigranulocytic. According to phenotype variability, 18 patients (29.5%) were classified as persistent eosinophilic, 17 (27.9%) non-persistent eosinophilic, and 26 (42.6%) intermittent eosinophilic. Smoking and recent asthma exacerbation were significantly associated with increased risk of variability of the IS inflammatory phenotype (OR = 6.44; p = .013; 95% CI = 1.49-27.80 and OR = 5.84; p = .022; 95% CI = 1.29-26.37, respectively). Conclusion: Half of asthma patients, predominantly those with eosinophilic phenotype, present a change in IS inflammatory phenotype. This variability is associated with smoking and recent asthma exacerbation. Data suggest these factors can modify the classification of IS inflammatory phenotype in clinical practice

Clinical and inflammatory features of asthma with dissociation between fractional exhaled nitric oxide and eosinophils in induced sputum.

BACKGROUND: Measurement of the fractional exhaled nitric oxide (FeNO) and eosinophils in induced sputum are noninvasive markers for assessing airway inflammation in asthma. The clinical usefulness of the correlation between raised FeNO and sputum eosinophilia is controversial. We aimed to examine dissociation between FeNO and sputum eosinophils in a clinical series of asthma patients and to determine whether dissociation between these noninvasive markers was associated with clinical and inflammatory differences in these patients. METHODS AND FINDINGS: A total of 110 patients with asthma were included in a cross-sectional study. All of them were on maintenance treatment for asthma. All patients underwent the following on the same day: FeNO, induced sputum, spirometry, serum total IgE levels and skin prick test. The level of asthma control was determined by the Asthma control Test Questionnaire. In 46 (41.8%) patients, a discrepancy between FeNO and sputum eosinophil count was observed, of those, 34 (73.9%) had a FeNO <50 ppb and high eosinophil count, and were characterized by having a predominance of nonallergic asthma with bronchial eosinophilic inflammatory phenotype. Also, 12 (26.1%) patients had FeNO ≥50 ppb and sputum eosinophilia within the normal reference values, and were characterized by having a predominance of atopy with a paucigranulocytic inflammatory phenotype. CONCLUSIONS: A high percentage of patients with dissociation between results of FeNO and sputum eosinophils was observed. These patients showed differential clinical and inflammatory features.

Utility of Induced Sputum in Routine Clinical Practice. / Utilidad del esputo inducido en la práctica clínica habitual.

OBJECTIVE: To determine the general and specific utility in diagnosis and/or treatment of induced sputum (IS) inflammatory cell counts in routine clinical practice. METHODS: Retrospective study of 171 patients referred for clinical sputum induction over a 1-year period in the pulmonology department of a referral hospital. Independent observers established whether the information provided by IS inflammatory cell count was useful for making diagnostic and therapeutic decisions. RESULTS: The most frequent reasons for determination of IS inflammatory cell count were: asthma 103 (59.20%); uncontrolled asthma 34 (19.54%); chronic cough 19 (10.9%), and gastroesophageal reflux 15 (8.6%). In 115 patients (67.3%) it was generally useful for diagnosis and/or treatment; in 98 patients (57.3%) it provided diagnostic information and in 85 patients (49.7%) it assisted in therapeutic decision-making. In asthma, uncontrolled asthma, chronic cough and gastroesophageal reflux, the results were useful in 71.8%, 67.6%, 47.4% and 60%, respectively. CONCLUSION: The information provided by IS inflammatory cell count is extremely useful in clinical practice, especially in asthma and chronic cough. These results may justify the inclusion of the IS technique in pulmonology departments and asthma units of referral centers.

Variability in Asthma Inflammatory Phenotype in Induced Sputum. Frequency and Causes.

INTRODUCTION: Recent studies have found variability in asthma inflammatory phenotypes determined by the inflammatory cells in induced sputum (IS). The aim of this study was to determine the frequency and factors affecting inflammatory phenotype variability in IS. METHODS: Retrospective observational study that included 61 asthmatic patients who underwent at least two IS tests over a period of 5 years. They were classified according to their baseline inflammatory phenotype and subsequently grouped according to phenotype variability (persistent eosinophilic, persistent non-eosinophilic and intermittent eosinophilic). Demographic, clinical and functional data and factors potentially influencing IS variability were collected in all cases. RESULTS: Of the 61 patients, 31 (50.8%) had a change with respect to baseline inflammatory phenotype. Of these, 16 (51.6%) were eosinophilic, 5 (16.1%) neutrophilic, 1 (3.2%) mixed and 9 (29.1%) paucigranulocytic. According to phenotype variability, 18 patients (29.5%) were classified as persistent eosinophilic, 17 (27.9%) non-persistent eosinophilic, and 26 (42.6%) intermittent eosinophilic. Smoking and recent asthma exacerbation were significantly associated with increased risk of variability of the IS inflammatory phenotype (OR=6.44; p=.013; 95% CI=1.49-27.80 and OR=5.84; p=.022; 95% CI=1.29-26.37, respectively). CONCLUSION: Half of asthma patients, predominantly those with eosinophilic phenotype, present a change in IS inflammatory phenotype. This variability is associated with smoking and recent asthma exacerbation. Data suggest these factors can modify the classification of IS inflammatory phenotype in clinical practice.

Secreted mucins and airway bacterial colonization in non-CF bronchiectasis.

BACKGROUND AND OBJECTIVE: Secreted mucins play a key role in antibacterial defence in the airway, but have not previously been characterized in non-cystic fibrosis (CF) bronchiectasis patients. We aim to investigate the relationship between secreted mucins levels and the presence of bacterial colonization due to potentially pathogenic microorganisms (PPM) in the airways of stable bronchiectasis patients. METHODS: Clinically stable bronchiectasis patients were studied prospectively at two centres. Patients with other pulmonary conditions were excluded. Spontaneous sputum was subject to bacterial culture, and secreted mucins (MUC2, MUC5AC and MUC5B) were measured in sputum supernatants by ELISA. RESULTS: A total of 50 patients were included. PPM were identified from sputum samples in 30 (60%), with Pseudomonas aeruginosa (n = 10) and Haemophilus influenzae (n = 10) as the most common PPM. There were no baseline differences among airway colonized and non-colonized patients. Patients with airways colonized by PPM presented higher levels of airway MUC2. No differences in MUC5AC levels were found among groups, whereas MUC5B levels were undetectable. Patients with P. aeruginosa colonization expressed the highest levels of MUC2. High levels of MUC2 and MUC5AC are also correlated with disease severity using the Bronchiectasis Severity Index. CONCLUSIONS: Airway MUC2 levels were higher in bronchiectasis patients colonized with PPM compared with those without airway colonization, especially in patients with P. aeruginosa. These findings suggest that airway-secreted mucins levels may play a role in the pathogenesis of airway infection in non-CF bronchiectasis.

Usefulness of the Exhaled Breath Temperature Plateau in Asthma Patients.

BACKGROUND: Exhaled breath temperature (EBT) has recently been proposed as a noninvasive marker of bronchial inflammation in patients with asthma. However, the usefulness of EBT in everyday clinical practice is not well established. Results to date are contradictory and are mainly derived from small, pediatric populations. A comparison of results is further complicated by the use of different equipment and measurements. OBJECTIVE: We performed a comprehensive study to determine whether EBT is related to asthma control, disease severity, bronchial obstruction, or bronchial inflammation. METHODS: Sixty-nine patients on maintenance treatment for asthma were included in a cross-sectional study. At the same visit, we measured the EBT plateau (EBTp) using an X-halo Breath Thermometer (Delmedica, Singapore), the fraction of exhaled nitric oxide (FeNO), spirometry, and inflammatory cell count in induced sputum, and we administered the Asthma Control Test questionnaire. RESULTS: No significant differences were found between EBTp measurements and the level of asthma control, disease severity, bronchial obstruction, FeNO levels, or inflammatory asthma phenotypes. We found a significant difference between EBTp and gender. The EBTp was 34.07°C (SD 0.74) in women and 34.38°C (0.46) in men (p = 0.038). We also found a significant correlation between EBTp measurements and the induced sputum eosinophil count (R = -0.348, p = 0.003). CONCLUSIONS: The results of this study do not support the usefulness of the EBTp in asthma management in routine clinical practice. Further research using standardized methods is needed to determine the potential use of the EBTp measurement in asthma management.