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Sputum induction is a technique that covers the induction and the subsequent processing of the expectorate primarily for the analysis of cells and different inflammatory biomarkers present in the airways to further understand the pathophysiology of different inflammatory respiratory disorders such as asthma and chronic obstructive pulmonary disease (COPD) as well as the diagnosis of lung diseases such as lung cancer, tuberculosis, and Pneumocystis jirovecii pneumonia. It is a non-invasive, safe, cost-effective, and reliable technique reported to exhibit a high success rate. However, due to being technically demanding and time-consuming and having the need of employing trained staff, this technique is only used in restricted research centres and in limited centres of clinical use. When the sputum is collected after induction, the primary goal is to obtain a differential cell count and evaluate the molecular biomarkers of airway inflammation such as eosinophil cationic protein, eosinophil-derived neurotoxin, major basic protein, tryptase, cytokine production [e.g., interleukin (IL)-5], albumin, and fibrinogen. In addition, cytospins from the processed sputum are used for immunocytochemical staining of cellular products such as EG-2 reactive protein, granulocyte-macrophage colony-stimulating factor, tumour necrosis factor alpha, and IL-8 that play significant roles in understanding the pathophysiology of inflammatory airway diseases. Nowadays, this technique can be further used by performing an additional analysis such as flow cytometry and in situ hybridisation on the sputum supernatant to investigate more the immune response and pathophysiological process of such various respiratory diseases. In addition, the application of sputum fluid phase to assess the biomarkers could be used more routinely in pathological laboratories for diagnosing lung cancer, COPD, and asthma as well as for monitoring lung cancer progression and asthma and COPD treatment, allowing for early detection and a better treatment provided by the clinicians.

Astrid Crespo-Lessmann,1– 3,* Elena Curto,1– 3,* Eder Freddy Mateus Medina,1– 3 Esther Palones,1– 3 Alicia Belda Soler,1– 3 Soraya Sánchez Maza,1– 3 Lorena Soto-Retes,1– 3 Vicente Plaza1– 3 1Servicio de Neumología y Alergia, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain; 2Institut d’Investigació Biomédica Sant Pau, Barcelona, Spain; 3Departament de Medicina, Universitat Autònoma de Barcelona, Barcelona, Spain*These authors contributed equally to this workCorrespondence: Astrid Crespo-Lessmann, Servicio de Neumología y Alergia, Hospital de la Santa Creu i Sant Pau, Carrer Mas Casanovas 90, Barcelona, 08041, Spain, Tel +34-935565972, Fax +34 935565601, Email acrespo@santpau.catPurpose: The objectives of this study were, for patients attending a specialist asthma clinic at a tertiary care hospital, to determine, from sputum induction (SI), proportions of bronchial inflammatory phenotypes, demographic, clinical and functional characteristics of each phenotype, and the most accessible non-invasive inflammatory marker that best discriminates between phenotypes.Patients and Methods: Included were 96 patients with asthma, attending a specialist asthma clinic at a tertiary care hospital, who underwent testing as follows: SI, spirometry, fractional exhaled nitric oxide (FeNO), blood eosinophilia, total immunoglobulin E (IgE), and a skin prick test.Results: SI phenotypes were 46.9% eosinophilic, 33.3% paucigranulocytic, 15.6% neutrophilic, and 4.2% mixed. No significantly different clinical or functional characteristics were observed between the phenotypes. A positive correlation was observed between SI eosinophilia and both emergency visits in the last 12 months (p = 0.041; r = 0.214) and FeNO values (p = 0.000; r = 0.368). Blood eosinophilia correlated with SI eosinophilia (p = 0.001; r = 0.362) and was the best predictor of bronchial eosinophilia, followed by FeNO, and total blood IgE (area under the receiver operating characteristic curve (AUC-ROC) 72%, 65%, and 53%, respectively), although precision was only fair.Conclusion: In consultations for severe asthma, the most frequent phenotype was eosinophilic. Peripheral blood eosinophilia is a reliable marker for discriminating between different bronchial inflammatory phenotypes, is useful in enabling doctors to select a suitable biologic treatment and so prevent asthma exacerbation, and is a better predictor of bronchial eosinophilia than FeNO and IgE values.Keywords: asthma, sputum induction, phenotype, eosinophilia

Background: Most studies assessing pathophysiological heterogeneity in asthma have been conducted in high-income countries (HICs), with little known about the prevalence and characteristics of different asthma inflammatory phenotypes in low-and middle-income countries (LMICs). This study assessed sputum inflammatory phenotypes in five centres, in Brazil, Ecuador, Uganda, New Zealand (NZ) and the United Kingdom (UK).Methods: We conducted a cross-sectional study of 998 asthmatics and 356 non-asthmatics in 2016-20. All centres studied children and adolescents (age range 8-20 years), except the UK centre which involved 26-27 year-olds. Information was collected using questionnaires, clinical characterization, blood and induced sputum.Results: Of 623 asthmatics with sputum results, 39% (243) were classified as eosinophilic or mixed granulocytic, i.e. eosinophilic asthma (EA). Adjusted for age and sex, with NZ as baseline, the UK showed similar odds of EA (odds ratio 1.04, 95% confidence interval 0.37-2.94) with lower odds in the LMICs: Brazil (0.73, 0.42-1.27), Ecuador (0.40, 0.24-0.66) and Uganda (0.62, 0.37-1.04). Despite the low prevalence of neutrophilic asthma in most centres, sputum neutrophilia was increased in asthmatics and non-asthmatics in Uganda.Conclusions: This is the first time that sputum induction has been used to compare asthma inflammatory phenotypes in HICs and LMICs. Most cases were non-eosinophilic, including in settings where corticosteroid use was low. A lower prevalence of EA was observed in the LMICs than in the HICs. This has major implications for asthma prevention and management, and suggests that novel prevention strategies and therapies specifically targeting non-eosinophilic asthma are required globally. [ABSTRACT FROM AUTHOR]

Flow cytometry is a classical approach used to define cell types in peripheral blood. While DNA methylation signatures have been extensively employed in recent years as an alternative to flow cytometry to define cell populations in peripheral blood, this approach has not been tested in lung-derived samples. Here, we compared bronchoalveolar lavage with a more cost-effective and less invasive technique based on sputum induction and developed a DNA methylome-based algorithm that can be used to deconvolute the cell types in such samples. We analysed the DNA methylome profiles of alveolar macrophages and lymphocytes cells isolated from the pulmonary compartment. The cells were isolated using two different methods, sputum induction and bronchoalveolar lavage. A strong positive correlation between the DNA methylome profiles of cells obtained with the two isolation methods was found. We observed the best correlation of the DNA methylomes when both isolation methods captured cells from the lower parts of the lungs. We also identified unique patterns of CpG methylation in DNA obtained from the two cell populations, which can be used as a signature to discriminate between the alveolar macrophages and lymphocytes by means of open-source algorithms. We validated our findings with external data and obtained results consistent with the previous findings. Our analysis opens up a new possibility to identify different cell populations from lung samples and promotes sputum induction as a tool to study immune cell populations from the lung.

Aleksandra Rybka-Fraczek, Marta Dabrowska, Elzbieta M Grabczak, Katarzyna Bialek-Gosk, Karolina Klimowicz, Olga Truba, Patrycja Nejman-Gryz, Magdalena Paplinska-Goryca, Rafal Krenke Department of Internal Medicine, Pulmonary Diseases and Allergy, Medical University of Warsaw, Warsaw, PolandCorrespondence: Marta Dabrowska, Tel +48 22 599 2599, Fax +48 22 599 1069, Email mdabrowska@mp.plBackground: Eosinophilic inflammatory phenotype was thought to be the most common phenotype of cough variant asthma (CVA), nevertheless other phenotypes were also reported.Purpose: The study aimed to analyze the inflammatory phenotypes of CVA in relation to treatment response to the stepwise anti-asthmatic treatment.Patients and Methods: The study included 45 patients with chronic cough (CC) and suspicion of CVA (normal chest X-ray, presence of bronchial hyperresponsiveness and no history of wheezing or dyspnea) in whom induced sputum was successfully collected. Based on the cellular composition of the sputum, patients were divided into major inflammatory phenotypes: eosinophilic, neutrophilic, paucigranulocytic or mixed granulocytic. A stepwise treatment, including inhaled corticosteroids with long-acting β2-agonist, montelukast and short-term therapy with prednisone was initiated. Good treatment response was defined as the reduction in cough severity at least 20 mm from the baseline in visual analogue scale and improvement in cough-related quality of life assessed by the Leicester cough questionnaire at least 1.3 points after any of three steps.Results: Finally, 40/45 (88.9%) patients improved after therapy. Eosinophilic asthma was found in 13/40 (32.5%) patients, neutrophilic in 6/40 (15.0%) and paucigranulocytic pattern in 21/40 (52.5%) patients. No one demonstrated a mixed granulocytic phenotype. The response to the treatment was similar in all groups. However, the reduction in cough severity was inversely related to the percentage of sputum neutrophils (r = − 0.44, P = 0.003). We showed that the percentage of neutrophils in sputum > 46% may be considered as a predictor of poor response to anti-asthmatic therapy.Conclusion: The diversity of inflammatory phenotypes with paucigranulocytic preponderance was found in subjects with CVA. The response to anti-asthmatic treatment in patients with CVA was not related to the inflammatory phenotype. High neutrophil count in sputum may predict poor response to anti-asthmatic therapy in patients with CC and bronchial hyperresponsiveness.Keywords: bronchial hyperresponsiveness, chronic cough, cough variant asthma, paucigranulocytic, neutrophils, sputum induction

Background: HIV infection and TB are two major public health problems in most of the developing countries including India. TB also the most common opportunistic infection seen in HIV infected patients in India 1,2. Tuberculosis is a significant increase in the worldwide incidence of TB which is contributed majorly by HIV infection. AIM: To study the role of Sputum Induction to aid in the diagnosis of Smear Negative or Sputum Scare Presumptive Pulmonary Tuberculosis in adults with HIV. OBJECTIVES: 1. By doing the Sputum Induction using the Hypertonic Saline Nebulisation 2. Performing the AFB Direct Smear and CBNAAT tests in that Induced Sputum sample. MATERIAL & METHODS: Study Design: Prospective hospital based observational study. Study area: The present study was conducted in the department of TB & Respiratory medicine, Osmania Medical College, Hyderabad. Study Period: Mar. 2021 - Feb. 2022. Study population: The subjects of the study were selected among the HIV positive with Presumptive Pulmonary Tuberculosis patients who visited the outpatient department or had been admitted in our hospital who agreed for voluntary participation Sample size: A total of 50 Presumptive Pulmonary Tuberculosis with HIV co- infection were taken as sample size. Sampling method: Simple random Sampling Technique. Results: In the present study 74% of cases were having scarce sputum & 26% of cases were having smear negative samples where the sputum specimen acquisition by sputum Induction needed for diagnosis of Pulmonary Tuberculosis. CONCLUSION: Sputum induction is a safe, simple and valuable procedure to obtain adequate sputum samples in suspected cases of pulmonary tuberculosis and can obviate the need for much sophisticated and invasive procedures like bronchoscopy. Sputum induction improves the diagnostic yield for AFB in patients unable to expectorate adequate sputum sample. [ABSTRACT FROM AUTHOR]

Background: Host innate immune cells have been identified as key players in the early eradication of Mycobacterium tuberculosis and in the maintenance of an anti-mycobacterial immune memory, which we and others have shown are induced through epigenetic reprogramming. Studies on human tuberculosis immunity are dominated by those using peripheral blood as surrogate markers for immunity. We aimed to investigate DNA methylation patterns in immune cells of the lung compartment by obtaining induced sputum from M. tuberculosis- exposed subjects including symptom-free subjects testing positively and negatively for latent tuberculosis as well as patients diagnosed with active tuberculosis. Alveolar macrophages and alveolar T cells were isolated from the collected sputum and DNA methylome analyses performed (Illumina Infinium Human Methylation 450 k). Results: Multidimensional scaling analysis revealed that DNA methylomes of cells from the tuberculosis-exposed subjects and controls appeared as separate clusters. The numerous genes that were differentially methylated between the groups were functionally connected and overlapped with previous findings of trained immunity and tuberculosis. In addition, analysis of the interferon-gamma release assay (IGRA) status of the subjects demonstrated that the IGRA status was reflected in the DNA methylome by a unique signature. Conclusions: This pilot study suggests that M. tuberculosis induces epigenetic reprogramming in immune cells of the lung compartment, reflected as a specific DNA methylation pattern. The DNA methylation signature emerging from the comparison of IGRA-negative and IGRA-positive subjects revealed a spectrum of signature strength with the TB patients grouping together at one end of the spectrum, both in alveolar macrophages and T cells. DNA methylation-based biosignatures could be considered for further development towards a clinically useful tool for determining tuberculosis infection status and the level of tuberculosis exposure. [ABSTRACT FROM AUTHOR]

• Bronchoalveolar lavage (BAL) and induced sputum (IS) samples were investigated. • Microbiota compartmentalisation of the lower airway occurs in children with CF. • This compartmentalisation presents difficulties for consistent lung sampling. • IS captures the lower airway microbiota signature of BAL in 80% of cases. Spatial topography of the cystic fibrosis (CF) lung microbiota is poorly understood in childhood. How best to sample the respiratory tract in children for microbiota analysis, and the utility of microbiota profiling in clinical management of early infection remains unclear. By comparison with bronchoalveolar lavage (BAL), we assessed the ability of induced sputum (IS) sampling to characterise the lower airway microbiota. Sample sets from IS and two or three matched BAL compartments were obtained for microbiota analysis as part of the CF-Sputum Induction Trial (UKCRN_14615, ISRCTNR_12473810). Microbiota profiles and pathogen detection were compared between matched samples. Twenty-eight patients, aged 1.1–17.7 years, provided 30 sample sets. Within-patient BAL comparisons revealed spatial heterogeneity in 8/30 (27%) sample sets indicating that the lower airway microbiota from BAL is frequently compartmentalised in children with CF. IS samples closely resembled one or more matched BAL compartments in 15/30 (50%) sets, and were related in composition in a further 9/30 (30%). IS detected 86.2% of the Top 5 genera found across matched BAL samples. The sensitivity of IS to detect specific CF-pathogens identified in matched BAL samples at relative abundance ≥5% varied between 43 and 100%, with negative predictive values between 73 and 100%. Spatial heterogeneity of the lower airway microbiota was observed in BAL samples and presents difficulties for consistent lung sampling. IS captured a microbiota signature representative of the lower airway in 80% of cases, and is a straightforward, non-invasive intervention that can be performed frequently to aid pathogen diagnosis and understand microbiota evolution in children with CF. [ABSTRACT FROM AUTHOR]

Flow cytometry is a classical approach used to define cell types in peripheral blood. While DNA methylation signatures have been extensively employed in recent years as an alternative to flow cytometry to define cell populations in peripheral blood, this approach has not been tested in lung-derived samples. Here, we compared bronchoalveolar lavage with a more cost-effective and less invasive technique based on sputum induction and developed a DNA methylome-based algorithm that can be used to deconvolute the cell types in such samples. We analysed the DNA methylome profiles of alveolar macrophages and lymphocytes cells isolated from the pulmonary compartment. The cells were isolated using two different methods, sputum induction and bronchoalveolar lavage. A strong positive correlation between the DNA methylome profiles of cells obtained with the two isolation methods was found. We observed the best correlation of the DNA methylomes when both isolation methods captured cells from the lower parts of the lungs. We also identified unique patterns of CpG methylation in DNA obtained from the two cell populations, which can be used as a signature to discriminate between the alveolar macrophages and lymphocytes by means of open-source algorithms. We validated our findings with external data and obtained results consistent with the previous findings. Our analysis opens up a new possibility to identify different cell populations from lung samples and promotes sputum induction as a tool to study immune cell populations from the lung. [ABSTRACT FROM AUTHOR]

Background: Sputum smear microscopy examination and culture for tuberculosis (TB) remain a fundamental tool of diagnosis but may be negative up to 50% case of active pulmonary TB. Bronchoscopy to obtain sputum is invasive and not readily available. Alternative methods of obtaining sputum specimens are crucial in suspected pulmonary TB cases who are unable to expectorate. In this context, it may be beneficial to stimulate sputum production by administering a mist of hypertonic saline produced by ultrasonic nebulization. The aims of the study are to describe the experience of a tertiary center in Saudi Arabia with sputum induction (SI) for the investigation of patients suspected to have sputum scare TB. Methods: A retrospective cohort study was performed. All patients suspected of sputum scare TB and investigated with SI were included. Standard descriptive statistics were used. Categorical data presented as frequency were compared using the Chi square test. Continuous data presented as mean ± standard deviation were compared using Student's t test. Sensitivity, specificity, and predictive values were calculated. Results: Of 252 patients with suspected TB who underwent SI, 78 (31%) were ultimately diagnosed to have TB. Culture of induced sputum confirmed the diagnosis of TB in 44 (56.4%) of these patients. However, the diagnosis of TB would have been missed in 13.5% of the cohort if no further investigations were done. The incidence of complications was low. No patients required hospitalization or specialist intervention. Conclusions: SI is safe well tolerated and inexpensive. It may reduce the need for bronchoscopy in patients with suspected sputum scare TB. However, around 20% of TB can be missed by SI unless further investigations are performed. Hence, patients suspected to have sputum scare TB in whom the risk of bronchoscopy is high, a clinical decision on the appropriateness of empirical therapy is often required.

Jie Gao, Feng Wu, Sifang Wu, Xing Yang Department of Pulmonary and Critical Care Medicine, Huizhou the Third People’s Hospital, Guangzhou Medical College, Huizhou 516002, People’s Republic of ChinaCorrespondence: Sifang Wu; Xing YangHuizhou the Third People’s Hospital, Guangzhou Medical College, 1# Xuebei Ave., Huizhou, Guangdong, 516002, ChinaTel +86-13502436132; +86-13528085770Fax +86 752-2359648Email wsf197906@126.com; 87575589@qq.comBackground: Measurement of sputum is used to define airway inflammatory phenotypes. Cough variant asthma (CVA) is considered to be the initial stage of classic asthma (CA). The aim of this study was to describe the association between the different subtypes of CVA and CA.Methods: A total of 459 patients with CVA and CA were screened for the study. All included patients performed spirometry, underwent a bronchial challenge with methacholine and induced sputum according to the guidelines.Results: A higher frequency of female patients were found with CVA and the eosinophilic airway inflammation of CVA than in CA and the noneosinophilic airway inflammation of CA (p=0.004 and p=0.024, respectively). Bronchial hyper-responsiveness (BHR) was lower in eosinophilic CVA and CA (p=0.006), while no difference was found in noneosinophilic CVA and CA. Association between the percentage of sputum eosinophils and the FEV1 level fell below 20% of the baseline value (PD20) in CVA and CA (r= − 0.1245, p=0.0357 and r= − 0.2148, p=0.0014, respectively).Conclusion: Eosinophilia may be associated with more severe disease, yet there was no difference in spirometry between the eosinophilic and noneosinophilic groups, and the BHR difference was not dramatic.Keywords: cough variant asthma, airway inflammatory types, sputum induction, bronchial hyper-responsiveness

Background: Sputum smear microscopy examination and culture for tuberculosis (TB) remain a fundamental tool of diagnosis but may be negative up to 50% case of active pulmonary TB. Bronchoscopy to obtain sputum is invasive and not readily available. Alternative methods of obtaining sputum specimens are crucial in suspected pulmonary TB cases who are unable to expectorate. In this context, it may be beneficial to stimulate sputum production by administering a mist of hypertonic saline produced by ultrasonic nebulization. The aims of the study are to describe the experience of a tertiary center in Saudi Arabia with sputum induction (SI) for the investigation of patients suspected to have sputum scare TB. Methods: A retrospective cohort study was performed. All patients suspected of sputum scare TB and investigated with SI were included. Standard descriptive statistics were used. Categorical data presented as frequency were compared using the Chi square test. Continuous data presented as mean ± standard deviation were compared using Student's t test. Sensitivity, specificity, and predictive values were calculated. Results: Of 252 patients with suspected TB who underwent SI, 78 (31%) were ultimately diagnosed to have TB. Culture of induced sputum confirmed the diagnosis of TB in 44 (56.4%) of these patients. However, the diagnosis of TB would have been missed in 13.5% of the cohort if no further investigations were done. The incidence of complications was low. No patients required hospitalization or specialist intervention. Conclusions: SI is safe well tolerated and inexpensive. It may reduce the need for bronchoscopy in patients with suspected sputum scare TB. However, around 20% of TB can be missed by SI unless further investigations are performed. Hence, patients suspected to have sputum scare TB in whom the risk of bronchoscopy is high, a clinical decision on the appropriateness of empirical therapy is often required. [ABSTRACT FROM AUTHOR]

OBJECTIVES: This study aimed to analyze the efficiency of physiotherapy techniques in sputum induction and in the evaluation of pulmonary inflammation in asthmatic children and adolescents. Although hypertonic saline (HS) is widely used for sputum induction (SI), specific techniques and maneuvers of physiotherapy (P) may facilitate the collection of mucus in some asthmatic children and adolescents. METHODS: A randomized crossover study was performed in patients with well-controlled asthma, and 90 sputum samples were collected. Children and adolescents were assessed using spirometry and randomized at entry into one of three sputum induction techniques: (i) 3% hypertonic saline – HS technique; (ii) physiotherapy (oscillatory positive expiratory pressure, forced expiration, and acceleration of expiratory flow) – P technique; and (iii) hypertonic saline + physiotherapy – HSP technique. ClinicalTrials.gov: NCT03136042. RESULTS: The total cells (mL) and the percentage (%) of differential inflammatory cells were similar in all techniques. The sputum weight (g) in the HSP technique was significantly higher than that in the HS technique. In all techniques, the percentage of viable cells was >50%, and there was no difference between the HS and P techniques. Moreover, sputum induction did not cause any alterations in the pulmonary function of patients. CONCLUSION: The physiotherapy sputum collection technique was effective in obtaining viable cells from mucus samples and yielded the same amount of sputum as the gold standard technique (hypertonic saline). In addition, the physiotherapy maneuvers were both safe and useful for sputum induction in asthmatic children and adolescents with well-controlled asthma.

Objective: Assisting to medical workers both of phthisiology institutions and primary health care in identifying and timely diagnosing tuberculosis (TB) in children. Methods: The data of state statistics analyzed on the total number of detected cases of tuberculosis and the number of identified cases of tuberculosis among children in the Republic of Tajikistan for 2013-2017. In addition, during the same period studied the data of all patients treated by tuberculosis at the Dushanbe City Children's Tuberculosis Hospital. Results: The ratio of active TB among children and adults in the period 2013-2017 ranged from 10.8% to 11.8%. The ratio of the number of sick children with multiple drug resistance of TB (MDR) to the total number of cases of child TB in the same period showed a tendency to increase from 4.3% to 6.5%. In 2017, the incidence of pulmonary TB with MBT (+) was 54.8%, including 16% for children aged 0-4 years, 37.5% for 5-14 years, and 69.3% for children aged 15-17 years. Conclusion: The tuberculosis process in children has its own features. Timely diagnostics, including the induced collection of bronchial secretion and application of the latest genetic technologies, greatly accelerates the verification process of the diagnosis and detection of both sensitive and resistant forms of Mycobacterium tuberculosis. There is an increase in the primary drug resistance of TB among children, which again confirms the need for a thorough examination of all contact persons.

Abstract Background Sputum induction with hypertonic saline in obstructive airway diseases is generally safe. However, saline induces bronchoconstriction in some patients despite pre-medication with Salbutamol. Our objectives were to investigate the predictors of failure of Salbutamol to protect against saline-induced-bronchoconstriction in patients with asthma and COPD and to evaluate implications for asthma therapy. Methods Retrospective survey on a database of 3565 patients with obstructive airway diseases who had sputum induced with hypertonic saline. The effect of baseline FEV1, bronchitis and concomitant medication on saline-induced-bronchoconstriction (≥ 15% drop in FEV1) were examined by logistic regression analysis. A subgroup had this re-examined 8–12 weeks after decreasing long-acting-beta-2-agonist dose or after adding Montelukast, which included an assessment of mast cell activity in sputum. Results 222 (6.2%) patients had saline-induced-bronchoconstriction despite pre-treatment with inhaled Salbutamol. Baseline airflow obstruction (FEV1% predicted

Single short-term exposures to ozone are known to cause acute changes in pulmonary function and neutrophilic airway inflammation. The respiratory health effects of repeated exposures are not as well studied. Pulmonary function decrements are known to attenuate, but it is less clear how injury and inflammation are affected. Using sputum induction (SI) to sample respiratory tract lining fluid after single- and multiday exposures, we designed a study to test the hypothesis that neutrophils would increase after multiday exposure compared with single-day exposure. In a randomized, crossover design, 15 normal healthy subjects were exposed to O3 (0.2 ppm) under two conditions: for 4 hr for 1 day (1D) and for 4 hr for 4 consecutive days (4D). Pulmonary function testing was performed immediately before and after each 4-hr exposure. The SI was performed 18 hr after the end of the 1D and 4D conditions. The symptom and pulmonary function data followed a pattern seen in other multiday O3 exposure studies, with the greatest changes occurring on the second day. In contrast to previous studies using bronchoalveolar lavage, however, there was a significant increase in the percentage of neutrophils and a significant decrease in the percentage of macrophages after the 4D condition compared with the 1D condition. Given that SI likely samples proximal airways better than distal lung, these results add to the body of evidence that differential airway compartmental responses to O3 occur in humans and other species.

Abstract Objective To compare the serum glycerophospholipid levels in the inflammatory subtypes of asthma by using targeted metabolomic analysis. Methods Demographic and clinical data were collected from 51 patients with asthma between January 2015 and December 2015. Routine blood and sputum induction tests were performed. Eosinophilic asthma was defined as induced sputum containing ≥ 3% eosinophils, and neutrophilic asthma, as induced sputum containing ≥ 71% neutrophils. Serum metabolic glycerophospholipid profile was determined by liquid chromatography-mass spectrometry. Differences in glycerophospholipid levels between eosinophilic and non-eosinophilic asthma and between neutrophilic and non-neutrophilic asthma were analyzed using partial least squares discriminant analysis. Results The serum lysophosphatidylglycerol level was significantly higher in the group with ≥ 3% eosinophils in sputum than in the group with < 3% eosinophils in sputum. The area under the receiver-operating characteristic curve was ≥ 70%. There was no significant difference in the serum metabolic glycerophospholipid profile between the group with sputum neutrophils ≥ 71% and the group with sputum neutrophils < 71%. Conclusion Serum lysophosphatidylglycerol is produced abundantly in eosinophilic asthma and may be a biomarker of eosinophilic asthma. This information is helpful for identifying and tailoring treatment for the common asthma subtypes. [ABSTRACT FROM AUTHOR]

Background Although sputum is a good specimen for various examinations, such as cytology and microbiological culture, sputum induction (SI) is not a routine procedure in children. Objective To identify the efficacy of SI to obtain specimen from lower respiratory tract in children, identify side effects of SI, and the results of microbiological examination. Methods A cross sectional study was performed in children (aged 1 month to 18 years) who underwent SI. Sputum induction was performed by inhalation with hypertonic solution, consisted of salbutamol for 15 minutes continued with NaCl 3% solution for another 15 minutes. Sputum specimens were examined for number of alveolar macrophage cell, surfactant protein A (SP-A) concentration, also acid-fast bacili smear, and M. tuberculosis culture, or aerobic microbial culture. Results Forty subjects with lower respiratory tract infection participated in this study, and SI was succesfully performed in all subjects. Youngest subject was 2 month old, the eldest was 16 year 7 month old. Median duration of SI was 45 minutes, and majority of volume was 3 or 4 mL. Side effects were nosebleeds (40%) and vomiting (2.5%). Macrophage alveolar more than 5 cells in one specimen was found in 97.5% subjects. Surfactant protein A examination was performed in 30 specimens, and SP-A was detected in all specimens (median concentration 264.528 pg/ mL). Culture for M. tuberculosis was positive in 1 of 27 subjects, while acid fast bacili smear was negative in all examined subjects. Aerobic microbial culture was positive in 5 of 13 subjects. Conclusions Sputum induction has good efficacy in obtaining lower respiratory tract specimen and it is safe to perform in children. Specimen from sputum induction yields good positive result for aerobic microbial cultures.

Background and objectives: It is known that chronic obstructive pulmonary disease (COPD) development process is imperceptible and can be asymptomatic for 20 or more years. It is of great importance to diagnose early inflammatory changes that can lead to COPD in young asymptomatic cigarette smokers. The aim of our study was to analyze the cell spectrum of induced sputum (IS) of young cigarette smokers, with emphasis on T-regulatory cells. Materials and methods: A total of 20 healthy nonallergic smokers, 20 nonsmokers and 20 COPD patients were enrolled in the study. After lung function measurements were taken, we performed sputum induction and analyzed sputum cells. We evaluated the cell count of FOXP3-positive, CD4+ and CD8+ T lymphocytes by immunocytochemistry staining, and the cell count of macrophages and neutrophils by May-Grünwald Giemsa staining. Results: Induced sputum of smokers contained a higher absolute amount of macrophages and neutrophils when compared to nonsmokers. FOXP3-positive cells in the sputum of young smokers showed a statistically significant increase when compared to nonsmokers. Induced sputum of COPD patients contained an increased absolute amount of neutrophils and FOXP3-positive Treg cells when compared to nonsmokers. Regression analysis showed that the amount of FOXP-3 positive cells, neutrophils and macrophages in the induced sputum was increasing with the number of pack years. Conclusions: This study demonstrates that young smokers have early inflammatory changes in their airways that not only initiate nonspecific mechanisms recruiting neutrophils, but also involve specific immune mechanisms with recruitment of T regulatory lymphocytes. The lymphocyte response is probably adaptive.

Sputum induction is a technique that covers the induction and the subsequent processing of the expectorate primarily for the analysis of cells and different inflammatory biomarkers present in the airways to further understand the pathophysiology of different inflammatory respiratory disorders such as asthma and chronic obstructive pulmonary disease (COPD) as well as the diagnosis of lung diseases such as lung cancer, tuberculosis, and Pneumocystis jirovecii pneumonia. It is a non-invasive, safe, cost-effective, and reliable technique reported to exhibit a high success rate. However, due to being technically demanding and time-consuming and having the need of employing trained staff, this technique is only used in restricted research centres and in limited centres of clinical use. When the sputum is collected after induction, the primary goal is to obtain a differential cell count and evaluate the molecular biomarkers of airway inflammation such as eosinophil cationic protein, eosinophil-derived neurotoxin, major basic protein, tryptase, cytokine production [e.g., interleukin (IL)-5], albumin, and fibrinogen. In addition, cytospins from the processed sputum are used for immunocytochemical staining of cellular products such as EG-2 reactive protein, granulocyte-macrophage colony-stimulating factor, tumour necrosis factor alpha, and IL-8 that play significant roles in understanding the pathophysiology of inflammatory airway diseases. Nowadays, this technique can be further used by performing an additional analysis such as flow cytometry and in situ hybridisation on the sputum supernatant to investigate more the immune response and pathophysiological process of such various respiratory diseases. In addition, the application of sputum fluid phase to assess the biomarkers could be used more routinely in pathological laboratories for diagnosing lung cancer, COPD, and asthma as well as for monitoring lung cancer progression and asthma and COPD treatment, allowing for early detection and a better treatment provided by the clinicians., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Goncalves and Eze.)

Highlights • Sputum induction maximizes the yield of the Xpert MTB/RIF test in patients with advanced HIV. • The urine lateral flow lipoarabinomannan (LAM) test decreases costs when diagnosing tuberculosis in patients with advanced HIV. • Sputum culture adds little to the diagnostic yield of Xpert MTB/RIF. Abstract Background Tuberculosis is a major cause of mortality among HIV-infected inpatients, and the World Health Organization (WHO) recommends an algorithm to improve diagnosis. The urine lateral flow lipoarabinomannan (LAM) and sputum Xpert MTB/RIF tests are promising tools, but the optimal diagnostic algorithm is unclear. Methods This prospective cohort study enrolled HIV-positive inpatients with cough and WHO danger signs. The Xpert MTB/RIF test and mycobacterial culture were performed on sputum using sputum induction when necessary, and the LAM test was performed on stored urine. Tuberculosis was diagnosed by culture from any site. The diagnostic accuracy and costs of testing were determined for single and combined tests. Results Tuberculosis was confirmed in 169 of 332 patients (50.9%). The yield of LAM, Xpert MTB/RIF on spontaneous sputum (Xpert Spot), and Xpert MTB/RIF on spontaneous or induced sputum (Xpert SI) was 35.5%, 23.1%, and 90.5%, respectively. When LAM was placed before Xpert Spot and Xpert SI in an algorithm, the yield was 50.9% and 92.3%, respectively. Adding culture to Xpert MTB/RIF only increased the yield by 1.2% and 2.7%, respectively. Use of the LAM test reduced costs. Conclusions Sputum induction is important to increase the yield of Xpert MTB/RIF for seriously ill patients with HIV and cough. LAM testing has little effect on yield when sputum induction is available, but reduces costs and may have other benefits. [ABSTRACT FROM AUTHOR]

Rationale: Acute respiratory effects of low-level ozone exposure are not well defined in older adults.Objectives: MOSES (The Multicenter Ozone Study in Older Subjects), although primarily focused on acute cardiovascular effects, provided an opportunity to assess respiratory responses to low concentrations of ozone in older healthy adults.Methods: We performed a randomized crossover, controlled exposure study of 87 healthy adults (59.9 ± 4.5 yr old; 60% female) to 0, 70, and 120 ppb ozone for 3 hours with intermittent exercise. Outcome measures included spirometry, sputum markers of airway inflammation, and plasma club cell protein-16 (CC16), a marker of airway epithelial injury. The effects of ozone exposure on these outcomes were evaluated with mixed-effect linear models. A P value less than 0.01 was chosen a priori to define statistical significance.Measurements and Main Results: The mean (95% confidence interval) FEV1 and FVC increased from preexposure values by 2.7% (2.0-3.4) and 2.1% (1.3-2.9), respectively, 15 minutes after exposure to filtered air (0 ppb). Exposure to ozone reduced these increases in a concentration-dependent manner. After 120-ppb exposure, FEV1 and FVC decreased by 1.7% (1.1-2.3) and 0.8% (0.3-1.3), respectively. A similar concentration-dependent pattern was still discernible 22 hours after exposure. At 4 hours after exposure, plasma CC16 increased from preexposure levels in an ozone concentration-dependent manner. Sputum neutrophils obtained 22 hours after exposure showed a marginally significant increase in a concentration-dependent manner (P = 0.012), but proinflammatory cytokines (IL-6, IL-8, and tumor necrosis factor-α) were not significantly affected.Conclusions: Exposure to ozone at near ambient levels induced lung function effects, airway injury, and airway inflammation in older healthy adults. Clinical trial registered with www.clinicaltrials.gov (NCT01487005). [ABSTRACT FROM AUTHOR]

Aim of the work: This study aimed to analyze induced sputum in asthmatic patients under different forms of treatment and study factors that may affect sputum cellularity in asthmatic patients. Patients and methods: Eighty asthmatic patients were included. Patients with contra-indication for sputum induction were excluded. Spirometer, sputum induction, sputum processing, sputum total cell count, viability, centrifugation, staining and count were done. Results: Eighty patients were included in the study to investigate induced sputum in asthmatic patients under different forms of treatment. Patient’s sex 43 (53.8%) male and 37 (46.2%) female patients were included. Their mean age ± SD was 32.05 ± 10.87 years. Sputum cell indices of asthmatic patients were 35.22% neutrophilic inflammation, 17.81% eosinophilic inflammation and the lymphocytic inflammation was 26.48%. Conclusion: Study concluded that the use of sputum induction as noninvasive measurements of airway inflammation in the diagnosis and management of asthma is very important for every patient diagnosed with bronchial asthma before starting asthma management and for asthmatic patients who were not controlled by full asthma management to understand the type of airway inflammation.

Introduction Bronchiectasis is a heterogeneous entity, taking into account clinical characteristics, inflammatory response, effectiveness of treatment and frequency of exacerbations. In stable state non-cystic fibrosis (non-CF) bronchiectasis, little is known about non-invasive techniques used for evaluating airway inflammation in obstructive airway diseases. Objectives We sought to evaluate the associations between induced sputum and clinical/radiologic characteristics, and the differences between biomarkers expressing Th1 and Th2 response in patients with non-CF bronchiectasis and to compare our findings with a previously studied population of patients with asthma and COPD. Methods We evaluated prospectively collected data from subjects with bronchiectasis. Comparisons were made between clinical, radiographic and physiologic characteristics, as well as induced sputum markers using appropriate statistical tools. We compared the levels of sputum markers with those of a previously studied cohort of asthma and COPD patients. Results We enrolled 40 subjects (21 men, mean age 63.5 yrs) with bronchiectasis. Fifteen subjects (37.5%) had a neutrophilic phenotype, 7 (17.5%) had an eosinophilic phenotype, 3 (12.5%) had a mixed neutrophilic-eosinophilic phenotype and 15 (37.5%) had a paucigranulocytic phenotype. Subjects with sputum neutrophilia had more severe bronchiectasis in HRCT and higher levels of IL-8 in sputum, whereas subjects with eosinophilia had higher levels of FeNO, greater bronchodilator reversibility and higher sputum IL-13. Sputum IL-8 levels were higher in subjects exhibiting frequent exacerbations and correlated with neutrophils in sputum (r = 0.799), the extent of bronchiectasis in HRCT (r = 0.765) and post-bronchodilator FEV 1 (r = −0.416). Sputum IL-13 levels correlated with sputum eosinophils (r = 0.656) and bronchodilator reversibility (r = 0.441). Neutrophilic bronchiectasis exhibited comparable IL-8 levels to COPD, whereas eosinophilic bronchiectasis showed significantly lower IL-13 levels compared to asthma. Conclusions Sputum cell counts and IL-8 and IL-13 correlate with distinct clinical and functional measurements of disease severity and therefore may have a role for non-invasively assessing inflammation in non-cystic fibrosis bronchiectasis. [ABSTRACT FROM AUTHOR]

"nBackground: Sputum induction has been recently introduced as an effective and inexpensive method for obtaining high quality sputum samples in patients without spontaneous sputum. As all Iranian physicians might not be familiar with this method yet, the results of this study could be of help in this regard. "n "nMethods: During June 2010 to January 2011, all pulmonary tuberculosis (PTB) suspected patients, with clinical and/or radiological evidence in favor of PTB who had been referred to the Pulmonary Diseases department of Imam Khomeini Medical Center were enrolled in the study, if they were without spontaneous sputum. Sputum induction was performed using ultrasound nebulized hypertonic 3% sterile saline for 20 minutes. The laboratory was requested to report if the samples were of the intended quality (Polymorphonuclear Cells/Squamus Epithelial Cells≥2). The patients' demographic data, HIV serology and chest radiological findings in favor of PTB were recorded and analyzed."n "nResults: In 50 patients with suspected PTB [23 men (mean age (±SD), 51.21±20.24) and 27 women (mean age (±SD) 55.40±18.00)], cough was the most common complaint. The most prevalent radiological findings were infiltration and consolidation. PPD was positive in 21 (42%) patients. Sputum induction led to obtaining proper sputum samples in 90% of the patients. Positive sputum smear and culture were seen in 13 (26%) cases."n "nConclusion: Sputum induction is a cost-effective and minimally invasive method which is associated with satisfactory results for obtaining high quality sputum samples in patients without spontaneous sputum.

Sputum induction by inhalation of hypertonic saline is a noninvasive, simple, cost effective and safe procedure to collect respiratory secre-tions from lung airways for diagnosis of various respiratory diseases. Sputum induction has higher yield in comparison to spontaneous sputum, BAL, bronchial washing and gastric lavage. It is widely used to assess airway inflammation in asthma and chronic obstructive pulmonary disease (COPD). It can be used as a complementary tool to BAL both in research and in clinical monitoring of patients with interstitial lung disease (ILD). The cells, recovered from spontaneous coughing can be used to study lung cancer, respiratory infections and in diagnosis of pneumocystis carinii pneumonia in patients infected with human immunodeficiency virus. In developing countries having high prevalence of pulmonary tuberculosis, sputum induction (SI) can increase the diagnostic yield, resulting in better categorization of patients for treatment purposes. It increases case detection rate of smear negative pulmonary tuberculosis specially in area where facili-ties for more invasive and expensive techniques are not available.

The technique of sputum induction improves the yield of microbiological investigations for organisms such as Mycobacterium tuberculosis and Pneumocystis carinii. The aim of the study was to determine the safety of this method in children under the age of 18 months. Heart rate and oxygen saturation were monitored during the procedure and compared with measurements obtained during the conventional method of sputum collection in the same patients. Patients were also observed for other possible side effects. Forty samples of sputa were obtained from 20 patients. No clinical differences in heart rate and oxygen saturation were found between the two methods. Overall, oxygen saturation measurements below 80% were recorded in three patients. Increased coughing and mild epistaxis did occur more frequently during the sputum induction method. It was concluded that sputum induction is safe in small children, but a larger sample size needs to be studied.

Background Little is known about the association between gender and risk of TB infection. We sought to assess the impact of gender on TB prevalence among people with presumptive tuberculosis at a regional referral hospital in a high TB and HIV prevalence setting. Methods We analyzed data from two diagnostic TB studies conducted in rural, southwestern Uganda. People with presumptive tuberculosis were evaluated by chest X-ray, fluorescence microscopy, TB culture, and HIV testing. Our primary outcome of interest was TB infection, as defined by a positive TB culture. Our primary explanatory variable of interest was gender. We fit univariable and multivariable logistic regression models to investigate associations between TB infection and gender, before and after adjusting or possible confounding factors, including ability to produce sputum, age and residence. Results Between April 2010 and September 2012, 863 people with presumptive tuberculosis (PWPTB) were enrolled in the two studies at Mbarara Regional Referral Hospital (MRRH) in Uganda. Among them 664 (76.9%) were able to produce sputum. X-ray was suggestive of TB for 258 (66.5%) of males and 175 (44.8%) of female (p < 0.001). using microscopy 84 (20%) of males and 48 (10.9%) of females were diagnosed with TB (p < 0.001) while 122 (30.3%) of males and 76 (18.4%) of females were diagnosed with TB (p < 0.001) using TB culture. In multivariable logistic regression models, the odds of having TB was higher in males than females (AOR 2.2 (1.56-3.18 95%CI°, P < 0.001), after adjustment for age, HIV status, ability to produce sputum, and residence. Conclusion In Southwestern Uganda, TB prevalence is higher among male than female people with presumptive TB. The increased risk of TB among males is independent of other TB risk factors. These findings emphasize the need for gender-focused interventions aimed at reducing TB transmission. [ABSTRACT FROM AUTHOR]

Sputum induction is a procedure used to help patients expectorate samples of sputum for laboratory analysis. It is a simple, safe and standardised procedure which may avoid the use of more invasive and potentially harmful interventions such as fibreoptic bronchoscopy. This article gives an overview of the uses in particular categories of patients, arguments for and against the procedure, and some local data. [ABSTRACT FROM AUTHOR]

Summary: Introduction: The GOLD guidelines advocate not to institute inhaled corticosteroids (ICS) in patients with mild-to-moderate COPD. However, many patients do use ICS and in some patients, withdrawal is associated with deteriorating lung function and increased exacerbation rates. Unfortunately, physicians do not know in which patients they can stop ICS treatment safely. Aim: To identify predictors of COPD exacerbations after ICS withdrawal. Methods: During ICS treatment, post-bronchodilator spirometry, body plethysmography, and health status assessment were performed in 68 COPD patients using ICS. Additionally, sputum cell differentials, supernatant leukotriene B4, eosinophilic cationic protein, and myeloperoxidase, serum C-reactive protein and soluble intracellular adhesion molecule, and urinary desmosine were assessed. Sputum was also analysed for mRNA levels of haemoxygenase-1, tumour necrosis factor-α, RANTES, interleukin 5(IL-5), IL-10, IL-12, IL-13, transforming growth factor-β, and interferon-γ. Statistics: Cox regression analyses were performed using time to exacerbation as outcome variable to identify significant hazards for a COPD exacerbation after ICS withdrawal. Results: Higher sputum % eosinophils, higher sputum MPO/neutrophil level, longer duration of COPD symptoms, <40 packyears smoking, and ICS withdrawal in November, December or January were significant hazards (all p <0.05) for experiencing a COPD exacerbation after ICS withdrawal in a monovariate model. In a multivariate model, all factors proved independent predictors except for sputum MPO/neutrophil level. Conclusions: Decisions on whether or not inhaled corticosteroids can be safely withdrawn in mild-to-moderate COPD can be facilitated by assessment of sputum inflammation, particularly eosinophil numbers, next to packyears smoking, season, and duration of COPD symptoms. [ABSTRACT FROM AUTHOR]

Summary: Background: Nitric oxide (NO) measurements in exhaled air and hypertonic saline-induced sputum are commonly used biomarker sampling methods of the lower airways. Both sampling methods have been validated in asthmatic patients and healthy controls, however, data from chronic smokers are scarce. Objectives: To evaluate the reproducibility and differences in fractional exhaled NO (FeNO) values in asymptomatic chronic smokers and healthy, non-smoking controls. Furthermore, to test the effect of hypertonic saline sputum induction (SI) on FeNO levels in both study groups. Methods: 16 asymptomatic chronic smokers and 16 non-smokers participated in this study. Baseline FeNO and forced expiratory volume in 1 s (FEV1) were recorded pre- and 30 min post NaCl 4.5% SI (3 × 5 min) on 2 study days (±2 h; 4–10 days apart). Mixed ANOVA was used to estimate the intra-subject Coefficient of Variation (CV) % over days; changes in FeNO and FEV1 values before and after SI, were analyzed by a Student''s paired t-test.The difference between smokers and non-smokers was estimated by a Student''s t-test. Results: On day 1, FeNO values in smokers were significantly lower than in non-smokers, 10.6 ppb, and 18.4 ppb, respectively, (42% difference, p = 0.0028, 95% CI: −59%, −19%). In both study groups, FeNO measurements were reproducible, with an intra-subject CV of 27.2% and 19.2%, for smokers and non-smokers, respectively. SI significantly decreased FeNO levels in both study groups on day 1. In smokers, there was a mean reduction in FeNO of almost 37% (p = 0.0045, 95% CI: −53%, −14%), and in non-smokers a mean decrease of almost 37% (95% CI : −53%, −14%; p = 0.0045). In both study groups SI did not affect FEV1 (p > 0.94). Conclusions: Our data extend previous findings in asthmatics and healthy controls to asymptomatic chronic smokers: 1. FeNO measurements are reproducible in both smokers and non-smokers; 2. baseline FeNO levels in chronic smokers are lower than in non-smokers and 3. sputum induction by hypertonic saline reduces FeNO levels in both study groups, without affecting lung function. [Copyright &y& Elsevier]

Objective -- To improve the aetiological diagnosis in community-acquired pneumonia (CAP) increased efforts were made to obtain expectorated sputum specimens from patients with CAP. Design -- A prospective, clinical study. Patients were encouraged to cough spontaneously and to expectorate a sputum specimen. If unsuccessful, they were asked to inhale nebulized hypertonic saline to induce secretion and cough. Setting -- One primary health care centre in Örebro, Sweden. Subjects -- Patients attending the Health Centre with acute symptoms of CAP. Main outcome measures -- Availability and quality of sputum specimen from patients with CAP in primary care. Results -- 177 patients were included, 63% were women and the mean age was 51 years. 28% were smokers and 46% showed infiltrates on chest X-ray. Sputum specimens were obtained from 125 patients. Fifty-nine were expectorated spontaneously and 66 were induced. Ninety-one of the specimens were found to be acceptable, whereas 34 were discarded. Potential pathogens were found in 57% of the 91 specimens. Conclusion -- Acceptable sputum specimens can be obtained with some effort from approximately half of the patients in primary care. Sputum culture might improve the knowledge of the bacterial aetiology of CAP in selected patients and in epidemiological studies. [ABSTRACT FROM AUTHOR]

Background: Sputum induction (SI) has proved to be a reliable non-invasive tool for sampling inflammatory airway contents in asthma, with distinct advantages over collection of expectorated sputum (ES) and bronchoalveolar lavage (BAL). A study was undertaken to evaluate the safety of SI and to assess if it might be an equally valuable outcome tool in patients with cystic fibrosis (CF).Methods: The safety of the procedure was examined and sample volume, cell counts, cytokine concentrations, and bacterial culture results obtained by SI, spontaneous ES, and fibreoptic bronchoscopy were compared in 10 adults with CF.Results: SI was well tolerated and was preferred to BAL by all subjects. The mean (SE) sample volume obtained by SI was significantly greater than ES (6.74 (1.46) ml v 1.85 (0.33) ml, p = 0.005). There was no significant difference in the number of cells per ml of sample collected. There was a difference in the mean (SD) percentage of non-epithelial, non-squamous cells collected (67 (28)%, 86 (21)%, and 99 (1)% for ES, SI, and BAL, respectively). These percentage counts were different between ES and both SI and BAL (p=0.03 and p=0.006, respectively). Cell differential counts (excluding squamous cells) from all collection methods were similar (mean (SD) 84 (9)%, 87 (7)%, and 88 (11)% polymorphonuclear cells for ES, SI, and BAL, respectively). The concentrations of interleukin (IL)-8 and tumour necrosis factor (TNF)-alpha were the same in all three samples when corrected for dilution using urea concentration. The test specific detection rate for recovery of bacteriological pathogens was 79% for SI, 76% for ES, and 73% for BAL.Conclusion: SI offers safety advantages over BAL and may be a more representative airway outcome measurement in patients with CF. [ABSTRACT FROM AUTHOR]