Clinically relevant subgroups in COPD and asthma.
; ; SCHLEICH, FLorence et al
in European respiratory review : an official journal of the European Respiratory Society (2015), 24(136), 283-98
As knowledge of airways disease has grown, it has become apparent that neither chronic obstructive pulmonary disease (COPD) nor asthma is a simple, easily defined disease. In the past, treatment options ... [more ▼]
As knowledge of airways disease has grown, it has become apparent that neither chronic obstructive pulmonary disease (COPD) nor asthma is a simple, easily defined disease. In the past, treatment options for both diseases were limited; thus, there was less need to define subgroups. As treatment options have grown, so has our need to predict who will respond to new drugs. To date, identifying subgroups has been largely reported by detailed clinical characterisation or differences in pathobiology. These subgroups are commonly called "phenotypes"; however, the problem of defining what constitutes a phenotype, whether this should include comorbid diseases and how to handle changes over time has led to the term being used loosely. In this review, we describe subgroups of COPD and asthma patients whose clinical characteristics we believe have therapeutic or major prognostic implications specific to the lung, and whether these subgroups are constant over time. Finally, we will discuss whether the subgroups we describe are common to both asthma and COPD, and give some examples of how treatment might be tailored in patients where the subgroup is clear, but the label of asthma or COPD is not. [less ▲]Detailed reference viewed: 15 (0 ULg)
Etude du phénotype mixte BPCO-asthme dans une série de patients BPCO en état stable
; NGUYEN DANG, Delphine ; SCHLEICH, FLorence et al
in Revue Médicale de Liège (2015), 70(1), 37-43
Résumé : Le but de ce travail était d’évaluer la prévalence et de décrire les caractéristiques du phénotype mixte BPCO-asthme parmi les patients BPCO stables de stade II à IV selon la classification de ... [more ▼]
Résumé : Le but de ce travail était d’évaluer la prévalence et de décrire les caractéristiques du phénotype mixte BPCO-asthme parmi les patients BPCO stables de stade II à IV selon la classification de GOLD. Matériel et méthodes : entre mai 2013 et avril 2014, 46 patients consécutifs furent recrutés à partir des consultations de Pneumologie du CHU de Liège. Ils étaient considérés comme présentant un syndrome mixte BPCO-asthme si leur indice de Tiffeneau était < 70% après bronchodilatation et s’accompagnait soit d’un antécédent d’asthme avant l’âge de 40 ans, soit d’au moins deux des trois critères suivants: 1) réversibilité bronchique significative (changement du VEMS après la bronchodilatation ≥ 200 ml et ≥ 12%), 2) inflammation éosinophilique: éosinophiles dans les expecto-rations ≥ 3% ou/et éosinophiles dans le sang ≥ 400/μl ou/et FENO ≥ 45 ppb, 3) histoire d’allergie respiratoire, ou IgE sériques totales ≥ 113 KU/l, ou RAST ≥ 0,35 KU/l à l’égard d’un des principaux aéroallergènes. Le phénotype mixte BPCO-asthme fut observé chez 37% des patients. L’expression symptomatique était plus marquée dans le groupe de phénotype mixte que dans le groupe de BPCO pure (CAT 24,6 ± 8,1 vs 19,4 ± 8, p < 0,05) en dépit d’un déficit spiro-métrique identique. Le coefficient de transfert alvéolo-capillaire (DLCO/VA%) était préservé dans le phénotype mixte (97 ± 24%) et supérieur à celui mesuré chez les patients BPCO pure (80 ± 20%) (p < 0,05). La prévalence du phéno-type mixte est voisine d’un tiers chez les patients BPCO et ces sujets ont une expression symptomatique plus marquée, sans signe d’obstruction bronchique plus sévère. [less ▲]Detailed reference viewed: 14 (1 ULg)
Diagnosis and clinical interest of asthma inflammatory phenotypes
Doctoral thesis (2014)Detailed reference viewed: 32 (5 ULg)
Heterogeneity of phenotypes in severe asthmatics. The Belgian Severe Asthma Registry (BSAR).
SCHLEICH, FLorence ; ; Louis, Renaud et al
in Respiratory medicine (2014), 108(12), 1723-32
The Belgian severe asthma registry is a web-based registry encompassing demographic, clinical, functional and inflammatory data of severe asthmatics (SA), aiming at improving awareness, knowledge on its ... [more ▼]
The Belgian severe asthma registry is a web-based registry encompassing demographic, clinical, functional and inflammatory data of severe asthmatics (SA), aiming at improving awareness, knowledge on its natural history and subphenotypes, and offering tools to optimize care of this asthma population. METHODS: The cross-sectional analyses of this registry included 350 SA as defined by the ATS (2000) from 9 Belgian centres, with at least one year follow up. RESULTS: Mean age was 55 +/- 14 yrs. SA were more frequently female (57%) and atopic (70%). Late-onset asthma (>/=40 yr) was observed in 31% of SA. Current smokers represented 12% while 31% were ex-smokers. In addition to high doses ICS + LABA, 65% of patients were receiving LTRA, 27% anti-IgE and 24% maintenance oral corticosteroids (8 mg (Interquartile range-IQR:4-8) methylprednisolone). Despite impaired airflow (median FEV1:67%; IQR: 52-81) only 65% had a post-bronchodilator FEV1/FVC ratio <70%. The median blood eosinophil count was 240/mm(3). The median FENO was 26 ppb (IQR: 15-43) and 22% of SA had FENO >/= 50 ppb. Induced sputum was successful in 86 patients. Eosinophilic asthma (sputum Eos >/= 3%) was the predominant phenotype (55%) while neutrophilic (sputum Neu >/= 76%) and paucigranulocytic asthma accounted for 22% and 17% respectively. Comorbidities included rhinitis and chronic rhinosinusitis (49%), nasal polyposis (19%), oesophageal reflux (36%), overweight and obesity (47%) and depression (19%). In addition, 8% had aspirin-induced asthma and 3% ABPA. Asthma was not well-controlled in 83% according to ACT < 20 and 77% with ACQ > 1.5. CONCLUSION: In this cohort of patients with severe asthma, the majority displayed indices of persistent airflow limitation and eosinophilic inflammation despite high-dose corticosteroids, suggesting potential for eosinophil-targeted biotherapies. [less ▲]Detailed reference viewed: 12 (0 ULg)
Thermoplastie bronchique : une réelle avancée dans le traitement de l'asthme
HEINEN, Vincent ; SCHLEICH, FLorence ; DUYSINX, Bernard et al
in Revue Médicale Suisse (2014), 10(439), 1544-1548
New treatments are needed to improve the care of severe asthmatic patients. Bronchial thermoplasty aims to lessen the airway smooth muscles via the heating of bronchial walls by radiofrequency. The ... [more ▼]
New treatments are needed to improve the care of severe asthmatic patients. Bronchial thermoplasty aims to lessen the airway smooth muscles via the heating of bronchial walls by radiofrequency. The preliminary studies showed a good tolerance and some good efficacy. Randomized controlled trials have been undertaken on moderate to severe asthmatic patients, demonstrating an improvement in quality of life, rate of severe exacerbations and unscheduled medical visits. The main side-effects consist of asthma exacerbations, atelectasis and infections. Bronchial thermoplasty is an innovative treatment with good efficacy and acceptable tolerance for moderate to severe asthmatic patients. More studies are needed to better understand its mechanism of action and more clearly delineate the precise indications of this innovative technique. [less ▲]Detailed reference viewed: 25 (5 ULg)
Phenotypes de la broncho-pneumopathie chronique obstructive.
Corhay, Jean-Louis ; SCHLEICH, FLorence ; Louis, Renaud
in Revue medicale de Liege (2014), 69(7-8), 415-21
Chronic Obstructive Pulmonary Disease (COPD) is a multi-dimensional disorder with multiple phenotypes. The GOLD guidelines, used for the diagnosis, staging and treatment of COPD, do not fully reflect the ... [more ▼]
Chronic Obstructive Pulmonary Disease (COPD) is a multi-dimensional disorder with multiple phenotypes. The GOLD guidelines, used for the diagnosis, staging and treatment of COPD, do not fully reflect the heterogeneous nature of the disease. Historically, the two most recognized clinical phenotypes of COPD are emphysema and chronic bronchitis. Most COPD patients encountered in practice actually share, both of these features. Genetic background, clinical presentation, variation in the response to treatment and propensity to exacerbations may also identify other phenotypes. Recently, using a mathematical approach, such as cluster analysis, which is based on pre-selected parameters, other interesting phenotypes were identified. A precise definition of COPD phenotypes should lead to a more targeted therapeutic approach based on these phenotypes. The purpose of this article is to point out that COPD is a heterogeneous disease and to summarize the current data available about the phenotypes of this disease. [less ▲]Detailed reference viewed: 27 (7 ULg)
Exhaled Air Analysis for Early Detection of Lung Cancer
Pesesse, Romain ; Stefanuto, Pierre-Hugues ; SCHLEICH, FLorence et al
Poster (2014, May 23)Detailed reference viewed: 40 (7 ULg)
Importance of concomitant local and systemic eosinophilia in uncontrolled asthma - Letter from the authors to editor
SCHLEICH, FLorence ; LOUIS, Renaud
in The European respiratory journal (2014), 44(4), 1098-9Detailed reference viewed: 18 (2 ULg)
Asthme bronchique non contrôlé : importance des phénotypes et de l'inflammation eosinophilique locale et systémique.
SCHLEICH, FLorence ; LOUIS, Renaud
in Revue Médicale de Liège (2014), 69 Spec No
Asthma is a complex chronic inflammatory disease of the airways. Eosinophilia is a recognized feature of asthma. Asthma is no more considered as a single disease, but there are several subtypes of ... [more ▼]
Asthma is a complex chronic inflammatory disease of the airways. Eosinophilia is a recognized feature of asthma. Asthma is no more considered as a single disease, but there are several subtypes of bronchial asthma, also called phenotypes, that have therapeutic and prognostic implications. Asthmatics are now classified according to inflammatory phenotypes that allow a personalized therapy. Phenotype identification requires induced sputum analysis that is not widely available. In this context, we have identified surrogate markers for inflammatory phenotypes. An eosinophilic phenotype can lbe suspected in case of concomitant increase of exhaled nitric oxide, blood eosinophils, IgE levels and airway obstruction. We have also identified a subgroup of asthmatics exhibiting diffuse local and systemic eosinophilia. This subgroup has a more severe asthma,a lower asthma control and a higher number of exacerbations. [less ▲]Detailed reference viewed: 20 (3 ULg)
Importance of concomitant local and systemic eosinophilia in uncontrolled asthma.
SCHLEICH, FLorence ; ; et al
in The European respiratory journal (2014), 44
Systemic and airway eosinophilia are recognised features of asthma. There are, however, patients who exhibit discordance between local and systemic eosinophilia. In this study, we sought to determine the ... [more ▼]
Systemic and airway eosinophilia are recognised features of asthma. There are, however, patients who exhibit discordance between local and systemic eosinophilia. In this study, we sought to determine the prevalence and characteristics of patients with concordant and discordant systemic and bronchial eosinophilia.We conducted a retrospective study on 508 asthmatics with successful sputum induction. We assessed the relationship between blood and sputum eosinophils by breaking down the population into four groups according to blood (>/=400 cells per mm3) and sputum (>/=3%) eosinophils. Then, we prospectively reassessed the link between eosinophils and asthma control (Asthma Control Questionnaire (ACQ)) and exacerbation rate in a new cohort of 250 matched asthmatics.In our retrospective cohort, asthmatics without eosinophilic inflammation were the largest group (49%). The group with isolated sputum eosinophilia (25%) was, compared with noneosinophilic asthma, associated with lower forced expiratory volume in 1 s (FEV1) and FEV1/forced vital capacity ratio and higher bronchial hyperresponsiveness and exhaled nitric oxide fraction (FeNO). Asthmatics exhibiting isolated systemic eosinophilia (7%) had similar characteristics as noneosinophilic asthmatics. The group with concordant systemic and airway eosinophilia (19%) showed remarkable male predominance, and had the lowest airway calibre, ACQ score and quality of life, and the highest bronchial hyperresponsiveness, FeNO and exacerbation rate. The prospective cohort confirmed the different subgroup proportions and the higher ACQ and exacerbation rates in cases of diffuse eosinophilia compared with noneosinophilic asthmatics.Concomitant systemic and bronchial eosinophilic inflammation contribute to poor asthma control. [less ▲]Detailed reference viewed: 35 (27 ULg)
Distribution of sputum cellular phenotype in a large asthma cohort: predicting factors for eosinophilic vs neutrophilic inflammation.
SCHLEICH, FLorence ; Manise, Maïté ; et al
in BMC Pulmonary Medicine (2013), 13(1), 11
ABSTRACT: BACKGROUND: Phenotyping asthma according to airway inflammation allows identification of responders to targeted therapy. Induced sputum is technically demanding. We aimed to identify predictors ... [more ▼]
ABSTRACT: BACKGROUND: Phenotyping asthma according to airway inflammation allows identification of responders to targeted therapy. Induced sputum is technically demanding. We aimed to identify predictors of sputum inflammatory phenotypes according to easily available clinical characteristics. METHODS: This retrospective study was conducted in 508 asthmatics with successful sputum induction recruited from the University Asthma Clinic of Liege. Receiver-operating characteristic (ROC) curve and multiple logistic regression analysis were used to assess the relationship between sputum eosinophil or neutrophil count and a set of covariates. Equations predicting sputum eosinophils and neutrophils were then validated in an independent group of asthmatics. RESULTS: Eosinophilic (>=3%) and neutrophilic (>=76%) airway inflammation were observed in 46% and 18% of patients respectively. Predictors of sputum eosinophilia >=3% were high blood eosinophils, FENO and IgE level and low FEV1/FVC. The derived equation was validated with a Cohen's kappa coefficient of 0.59 (p < 0.0001). ROC curves showed a cut-off value of 220/mm3 (AUC = 0.79, p < 0.0001) or 3% (AUC = 0.81, p < 0.0001) for blood eosinophils to identify sputum eosinophilia >=3%. Independent predictors of sputum neutrophilia were advanced age and high FRC but not blood neutrophil count. CONCLUSION: Eosinophilic and paucigranulocytic asthma are the dominant inflammatory phenotypes. Blood eosinophils provide a practical alternative to predict sputum eosinophilia but sputum neutrophil count is poorly related to blood neutrophils. [less ▲]Detailed reference viewed: 19 (2 ULg)
Sputum IgE and Cytokines in Asthma: Relationship with Sputum Cellular Profile.
Manise, Maïté ; ; et al
in PLoS ONE (2013), 8(3), 58388
BACKGROUND: Local IgE production may play a role in asthma pathogenesis. The aim of the study was to assess sputum total IgE and cytokines in asthmatics according to sputum cellular phenotype. METHODS: We ... [more ▼]
BACKGROUND: Local IgE production may play a role in asthma pathogenesis. The aim of the study was to assess sputum total IgE and cytokines in asthmatics according to sputum cellular phenotype. METHODS: We studied 122 subjects including 22 non atopic healthy subjects, 41 eosinophilic (sputum eosinophils >/=3%), 16 neutrophilic (sputum neutrophils >76%) and 43 pauci-granulocytic asthmatics (sputum eosinophils <3% and sputum neutrophils </=76%) recruited from the asthma clinic at CHU Liege. Sputum supernatant total IgE (tIgE) was measured by ImmunoCAP and sputum supernatant cytokines (IL-4, IL-5, IL-6, IL-10, IL-13, IL-17, IFN-gamma and TNF-alpha) were measured with the Luminex xMAP Technology by using commercially available Fluorokine MAP kits. RESULTS: After concentrating sputum samples, total IgE was detectable in the majority of subjects. Sputum IgE was raised in asthmatics when compared to healthy subjects. Overall, asthmatics did not significantly differ from healthy subjects with respect to cytokine levels. The eosinophilic asthma phenotype, however, was characterised by raised sputum tIgE, IL-5 and IL-13 compared to healthy subjects (p<0.001, p<0.001 and p<0.05 respectively) and pauci-granulocytic asthma (p<0.01, p<0.001 and p<0.05 respectively) and raised IL-5 compared to neutrophilic asthma (p<0.01). When patients were classified according to sputum IgE levels, it appeared that IL-5, IL-6, IL-17 and TNF-alpha sputum supernatant levels were raised in the "IgE high" asthmatics (IgE >/=0.1 kU/l) when compared to "IgE low" asthmatics (IgE<0.1 kU/l). CONCLUSION: The eosinophilic asthma phenotype was associated with raised sputum IgE and a Th2 cytokine profile. Raised sputum IgE was associated with a heterogeneous cytokine overproduction. [less ▲]Detailed reference viewed: 25 (4 ULg)
Intérêt de la mesure de l'inflammation en clinique dans l'asthme.
SCHLEICH, FLorence ; LOUIS, Renaud
in EMC Pneumologie (2012)Detailed reference viewed: 27 (10 ULg)
Corticosteroids: still at the frontline in asthma treatment?
LOUIS, Renaud ; SCHLEICH, FLorence ;
in Clinics in Chest Medicine (2012), 33(3), 531-41
Inhaled corticosteroids (ICS) have led to improved asthma control and reduced asthma mortality in the Western world. ICS are effective in combating T-helper type 2-driven inflammation featuring mast cell ... [more ▼]
Inhaled corticosteroids (ICS) have led to improved asthma control and reduced asthma mortality in the Western world. ICS are effective in combating T-helper type 2-driven inflammation featuring mast cell and eosinophilic airway infiltration. Their effect on innate immunity-driven neutrophilic inflammation is poor and their ability to prevent airway remodeling and accelerated lung decline is controversial. Although ICS remain pivotal drugs in asthma management, research is needed to find drugs complementary to the combination ICS/long-acting beta2-agonist in refractory asthma and perhaps a new class of drugs as a first-line treatment in mild to moderate noneosinophilic asthma. [less ▲]Detailed reference viewed: 65 (20 ULg)
Is FE(NO50) useful diagnostic tool in suspected asthma?
SCHLEICH, FLorence ; ASANDEI, Raluca ; Manise, Maïté et al
in International Journal of Clinical Practice (2012), 66(2), 158-65
Background: Asthma diagnosis is based on the presence of symptoms and the demonstration of airflow variability. Airway inflammation measured by fractional exhaled nitric oxide, measured at a flow rate of ... [more ▼]
Background: Asthma diagnosis is based on the presence of symptoms and the demonstration of airflow variability. Airway inflammation measured by fractional exhaled nitric oxide, measured at a flow rate of 50 ml/s (FE(NO50) ) remains a controversial diagnostic tool. Aim: To assess the ability of FE(NO50) to identify bronchial hyperresponsiveness (BHR) to methacholine (provocative concentration of methacholine causing a 20% fall in FEV(1) ; PC20M </= 16 mg/ml) and to establish whether or not symptoms relate to FE(NO50) and PC20M in patients with no demonstrated reversibility to beta(2) -agonist. Methods: We conducted a prospective study on 174 steroid naive patients with respiratory symptoms, forced expiratory volume in 1 s (FEV(1) ) >/= 70% predicted and no demonstrated reversibility to beta(2) -agonist. Patients answered to a standardised symptom questionnaire and underwent FE(NO50) and methacholine challenge. Receiver-operating characteristic (ROC) curve and logistic regression analysis assessed the relationship between PC20M and FE(NO50) , taking into account covariates (smoking, atopy, age, gender and FEV(1) ). Results: A total of 82 patients had a PC20M </= 16 mg/ml and had significantly higher FE(NO50) (19 ppb vs. 15 ppb; p < 0.05). By constructing ROC curve, we found that FE(NO50) cut-off value of 34 ppb was able to identify not only BHR with high specificity (95%) and positive predictive value (88%) but low sensitivity (35%) and negative predictive value (62%). When combining all variables into the logistic model, FE(NO50) (p = 0.0011) and FEV(1) (p < 0.0001) were independent predictors of BHR whereas age, gender, smoking and atopy had no influence. The presence of diurnal and nocturnal wheezing was associated with raised FE(NO50) (p < 0.001 and p < 0.05, respectively). Conclusion: The value of FE(NO50) > 34 ppb has high predictive value of PC20M < 16 in patients with suspected asthma in whom bronchodilating test failed to demonstrate reversibility or was not indicated. However, FE(NO50) </= 34 ppb does not rule out BHR and should prompt the clinician to ask for a methacholine challenge. [less ▲]Detailed reference viewed: 42 (13 ULg)
Les traitements cibles dans l'asthme: confirmations, espoirs et deceptions.
SCHLEICH, FLorence ; LOUIS, Renaud
in Revue Médicale de Liège (2012), 67 Spec No
Asthma is a chronic inflammatory disease of the airways. The inflammatory process is driven by different pathways involving cytokines and other protein mediators. Patients with severe asthma are at high ... [more ▼]
Asthma is a chronic inflammatory disease of the airways. The inflammatory process is driven by different pathways involving cytokines and other protein mediators. Patients with severe asthma are at high risk of severe exacerbations and death and have few therapeutic options available. Therefore, biological agents have been developed to help patients with refractory asthma by interfering with several compounds of the asthma inflammatory cascade. In addition to decreasing exacerbations, some of those treatments have a steroid sparing role and many beneficial effects in asthmatics. [less ▲]Detailed reference viewed: 58 (4 ULg)
L'asthme: une maladie complexe mettant en jeu facteurs environnementaux et terrain genetique.
LOUIS, Renaud ; SCHLEICH, FLorence ; Corhay, Jean-Louis et al
in Revue Médicale de Liège (2012), 67(5-6), 286-91
Asthma is a complex disease highly dependent of environmental exposure and genetic background. Through linkage analysis, positional cloning and genome wide association studies, novel asthma genes have ... [more ▼]
Asthma is a complex disease highly dependent of environmental exposure and genetic background. Through linkage analysis, positional cloning and genome wide association studies, novel asthma genes have come out such as ADAM-33 or ORMLD3. Important environmental factors include allergenic exposure, pollutants and especially particulate matters, tobacco, aerosol exposure, viral infections and level of exposure to endotoxin. The effects of environmental factors are modulated by the genetic sequence and numerous single nucleotide polymorphisms (SNPs). Recently, it has also become clear that environmental factors may alter gene expression by DNA methylation or histone methylation/acetylation without changing the gene sequence and thereby changing asthmatic phenotype. [less ▲]Detailed reference viewed: 129 (7 ULg)
Disturbed Cytokine Production at the Systemic Level in Difficult-to-Control Atopic Asthma: Evidence for Raised Interleukin-4 and Decreased Interferon-gamma Release following Lipopolysaccharide Stimulation.
MANISE, Maïté ; SCHLEICH, FLorence ; QUAEDVLIEG, Valérie et al
in International Archives of Allergy & Immunology (2012), 158(1), 1-8
Background: Disturbed cytokine production is thought to govern inflammation in asthma, which, in its turn, may lead to uncontrolled disease. The aim of this study was to assess the relationship between ... [more ▼]
Background: Disturbed cytokine production is thought to govern inflammation in asthma, which, in its turn, may lead to uncontrolled disease. The aim of this study was to assess the relationship between cytokine production from blood leucocytes and the level of asthma control. Methods: We compared the production of interleukin (IL)-4, IL-6, IL-10, interferon (IFN)-gamma and tumour necrosis factor-alpha from peripheral blood leucocytes in non-atopic healthy subjects (n = 22), atopic non-asthmatics (n = 10), well-controlled asthmatics [Juniper asthma control questionnaire (ACQ) score <1.5; n = 20] and patients with uncontrolled asthma despite inhaled or oral corticoids (ACQ score >/=1.5; n = 20). Fifty microlitres of peripheral blood was incubated for 24 h with RPMIc, lipopolysaccharide (LPS; 1 ng/ml) or phytohaemagglutinin (1 mug/ml), and cytokines were measured by immunotrapping (ELISA). Results: Both controlled and uncontrolled asthmatics as well as atopic non-asthmatics spontaneously produced more IL-4 than non-atopic healthy subjects (p < 0.001). IL-4 production induced by LPS was significantly greater (p < 0.05) in both asthma groups compared to atopic non-asthmatics and non-atopic healthy subjects. By contrast, IFN-gamma release induced by LPS was lower in uncontrolled asthmatics than in non-atopic healthy subjects (p < 0.05) and controlled asthmatics (p < 0.05). IL-10 release after LPS was greater in uncontrolled asthmatics than in atopic non-asthmatics (p < 0.05). No difference was observed regarding other cytokines. Conclusion: Blood cells from patients with difficult-to-control atopic asthma display highly skewed Th2 cytokine release following LPS stimulation. [less ▲]Detailed reference viewed: 42 (8 ULg)
Induced sputum in asthma: from bench to bedside.
; SCHLEICH, FLorence ; et al
in Current medicinal chemistry (2011), 18(10), 1415-22
During recent years there has been a growing interest in using non-invasive biomarkers to understand and monitor the airway inflammation in subjects with respiratory tract disorders and mainly asthma and ... [more ▼]
During recent years there has been a growing interest in using non-invasive biomarkers to understand and monitor the airway inflammation in subjects with respiratory tract disorders and mainly asthma and chronic obstructive pulmonary disease (COPD). Sputum induction is generally a well-tolerated and safe procedure and a European Respiratory Society Task Force has published a comprehensive review on sputum methodology. Induced sputum cell count and, to a lesser extent, mediator measurements have been particularly well validated. In asthma, the sputum and the cell culture supernatant can be used for the measurement of a variety of soluble mediators, including eosinophil-derived proteins, nitric oxide (NO) derivatives, cytokines and remodelling-associated proteins. Sputum eosinophilia (> 3%) is a classic feature of asthma although half of the patients seems to be non eosinophilic. Measuring the percentage of sputum eosinophils has proved to be useful in the clinical arena in helping to predict short term response to inhaled corticosteroids (ICS) and tailor the dose of ICS in the severe patients but there is scope for the application of other induced sputum markers potentially useful in clinical practice. The widespread application of induced sputum in asthma across the spectrum of disease severity has given insight into the relationship between airway function and airway inflammation, proposed new disease phenotypes and defined which of these phenotypes respond to current therapy, and perhaps most importantly provided an additional tool to guide the clinical management of asthmatic patients. To date sputum induction is the only non-invasive measure of airway inflammation that has a clearly proven role in asthma management. [less ▲]Detailed reference viewed: 41 (2 ULg)