151
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Once-daily inhaled glucocorticosteroid administration in controlled asthma patients. Pulm Pharmacol Ther 2008; 21:663-7. [PMID: 18479954 DOI: 10.1016/j.pupt.2008.03.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2007] [Revised: 03/25/2008] [Accepted: 03/26/2008] [Indexed: 11/21/2022]
Abstract
BACKGROUND Inhaled glucocorticosteroids are usually administered in two equal daily doses. To simplify the method of treatment, once-daily administration has been used. However, little information regarding whether once-daily treatment can sufficiently control airway inflammation is available. We aimed to investigate whether once-daily administration of inhaled glucocorticosteroids can control airway inflammation. METHODS Twenty-four well-controlled asthma patients were enrolled in a randomized crossover trial to compare the efficacies of once-daily and twice-daily administration of inhaled glucocorticosteroids. Initially, the patients were randomly assigned to receive either once-daily or twice-daily administration for 16 weeks. After an 8-week washout period, patients who originally received twice-daily administration were assigned to once-daily administration for 16 weeks and vice versa. We assessed the changes in the forced expiratory volume in 1s, morning and evening peak expiratory flows, asthma symptoms, health-related quality of life and fractional exhaled nitric oxide levels. RESULTS Patients with once-daily administration showed the same level of clinical control and lung functions as patients receiving twice-daily administration. There was no difference in the fractional exhaled nitric oxide levels between the beginning and end of the twice-daily treatment (35.69 and 33.23ppb, respectively). In contrast, the fractional exhaled nitric oxide level was significantly higher at the end of the once-daily treatment (33.87 and 39.38ppb, respectively, p< 0.001). CONCLUSION Although once-daily administration is sufficient for clinical control of asthma, it might not control airway inflammation sufficiently.
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152
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Martins P, Caires I, Pinto JR, da Mata PL, Torres S, Valente J, Borrego C, Neuparth N. Medição do óxido nítrico no ar exalado: Utilização na avaliação de crianças com história de sibilância. REVISTA PORTUGUESA DE PNEUMOLOGIA 2008. [DOI: 10.1016/s0873-2159(15)30230-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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153
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Bohadana A, Michaely JP, Teculescu D, Wild P. Reproducibility of exhaled nitric oxide in smokers and non-smokers: relevance for longitudinal studies. BMC Pulm Med 2008; 8:4. [PMID: 18304367 PMCID: PMC2292677 DOI: 10.1186/1471-2466-8-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2007] [Accepted: 02/28/2008] [Indexed: 11/10/2022] Open
Abstract
Background Currently, there is much interest in measuring fractional exhaled nitric oxide (FENO) in populations. We evaluated the reproducibility of FENO in healthy subjects and determined the number of subjects necessary to carry out a longitudinal survey of FENO in a population containing smokers and non-smokers, based on the assessed reproducibility. Methods The reproducibility of FENO was examined in 18 healthy smokers and 21 non-smokers. FENO was assessed once at 9 AM on five consecutive days; in the last day this measurement was repeated at 2 PM. Respiratory symptoms and medical history were assessed by questionnaire. The within- and between-session repeatability of FENO and log-transformed FENO was described. The power of a longitudinal study based on a relative increase in FENO was estimated using a bilateral t-test of the log-transformed FENO using the between-session variance of the assay. Results FENO measurements were highly reproducible throughout the study. FENO was significantly higher in males than females regardless of smoking status. FENO was positively associated with height (p < 0.001), gender (p < 0.034), smoking (p < 0.0001) and percent FEV1/FVC (p < 0.001) but not with age (p = 0.987). The between-session standard deviation was roughly constant on the log scale. Assuming the between-session standard deviation is equal to its longitudinal equivalent, either 111 or 29 subjects would be necessary to achieve an 80% power in detecting a 3% or a 10% increase in FENO respectively. Conclusion The good reproducibility of FENO is not influenced by gender or smoking habits. In a well controlled, longitudinal study it should allow detecting even small increases in FENO with a reasonable population size.
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Affiliation(s)
- Abraham Bohadana
- Institut National de la Santé et de la Recherche Médicale, INSERM, ERI 11, 54505 Vandoeuvre - lès-Nancy, France.
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154
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Louhelainen N, Myllärniemi M, Rahman I, Kinnula VL. Airway biomarkers of the oxidant burden in asthma and chronic obstructive pulmonary disease: current and future perspectives. Int J Chron Obstruct Pulmon Dis 2008; 3:585-603. [PMID: 19281076 PMCID: PMC2650600 DOI: 10.2147/copd.s3671] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The pathogenesis of asthma and chronic obstructive pulmonary disease (COPD) has been claimed to be attributable to increased systemic and local oxidative stress. Detection of the oxidant burden and evaluation of their progression and phenotypes by oxidant biomarkers have proved challenging and difficult. A large number of asthmatics are cigarette smokers and smoke itself contains oxidants complicating further the use of oxidant biomarkers. One of the most widely used oxidant markers in asthma is exhaled nitric oxide (NO), which plays an important role in the pathogenesis of asthma and disease monitoring. Another oxidant marker that has been widely investigated in COPD is 8-isoprostane, but it is probably not capable of differentiating asthma from COPD, or even sensitive in the early assessment of these diseases. None of the current biomarkers have been shown to be better than exhaled NO in asthma. There is a need to identify new biomarkers for obstructive airway diseases, especially their differential diagnosis. A comprehensive evaluation of oxidant markers and their combinations will be presented in this review. In brief, it seems that additional analyses utilizing powerful tools such as genomics, metabolomics, lipidomics, and proteomics will be required to improve the specificity and sensitivity of the next generation of biomarkers.
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Affiliation(s)
- Noora Louhelainen
- Department of Medicine, Division of Pulmonary Medicine, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland
| | - Marjukka Myllärniemi
- Department of Medicine, Division of Pulmonary Medicine, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland
| | - Irfan Rahman
- Department of Environmental Medicine and the Lung Biology and Disease Program, University of Rochester Medical Center, Rochester, New York, USA
| | - Vuokko L Kinnula
- Department of Medicine, Division of Pulmonary Medicine, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland
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155
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Cobos Barroso N, Pérez-Yarza EG, Sardón Prado O, Reverté Bover C, Gartner S, Korta Murua J. Óxido nítrico exhalado en niños: un indicador no invasivo de la inflamación de las vías aéreas. Arch Bronconeumol 2008. [DOI: 10.1157/13114655] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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156
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[Analysis of induced sputum in refractory asthma]. Presse Med 2007; 37:155-9. [PMID: 18061391 DOI: 10.1016/j.lpm.2007.05.033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2007] [Accepted: 05/10/2007] [Indexed: 11/20/2022] Open
Abstract
Induction of sputum by inhalation of hypertonic or isotonic fluid makes possible the safe and noninvasive harvesting of airway cells from patients with asthma, regardless of disease severity. Analysis of sputum cells has helped to identify different phenotypes of refractory asthma and shown that such asthma can be eosinophilic, neutrophilic, or both. Elevated eosinophil levels in sputum indicate a risk of exacerbation if the corticosteroid dose is reduced in stabilized patients. Surveillance of eosinophilia levels as an indicator for corticosteroid adjustment in refractory asthma makes it possible to reduce the frequency of severe exacerbations.
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157
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Taylor DR, Mandhane P, Greene JM, Hancox RJ, Filsell S, McLachlan CR, Williamson AJ, Cowan JO, Smith AD, Sears MR. Factors affecting exhaled nitric oxide measurements: the effect of sex. Respir Res 2007; 8:82. [PMID: 18005450 PMCID: PMC2231356 DOI: 10.1186/1465-9921-8-82] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2007] [Accepted: 11/15/2007] [Indexed: 11/29/2022] Open
Abstract
Background Exhaled nitric oxide (FENO) measurements are used as a surrogate marker for eosinophilic airway inflammation. However, many constitutional and environmental factors affect FENO, making it difficult to devise reference values. Our aim was to evaluate the relative importance of factors affecting FENO in a well characterised adult population. Methods Data were obtained from 895 members of the Dunedin Multidisciplinary Health and Development Study at age 32. The effects of sex, height, weight, lung function indices, smoking, atopy, asthma and rhinitis on FENO were explored by unadjusted and adjusted linear regression analyses. Results The effect of sex on FENO was both statistically and clinically significant, with FENO levels approximately 25% less in females. Overall, current smoking reduced FENO up to 50%, but this effect occurred predominantly in those who smoked on the day of the FENO measurement. Atopy increased FENO by 60%. The sex-related differences in FENO remained significant (p < 0.001) after controlling for all other significant factors affecting FENO. Conclusion Even after adjustment, FENO values are significantly different in males and females. The derivation of reference values and the interpretation of FENO in the clinical setting should be stratified by sex. Other common factors such as current smoking and atopy also require to be taken into account.
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Affiliation(s)
- D Robin Taylor
- Department of Respiratory Medicine, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand.
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158
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Hahn PY, Morgenthaler TY, Lim KG. Use of exhaled nitric oxide in predicting response to inhaled corticosteroids for chronic cough. Mayo Clin Proc 2007; 82:1350-5. [PMID: 17976354 DOI: 10.4065/82.11.1350] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
OBJECTIVE To evaluate our experience with patients who presented with chronic cough and how exhaled nitric oxide predicted response to inhaled corticosteroid (ICS) therapy. PATIENTS AND METHODS This retrospective observational study of 114 patients evaluated for chronic cough with measured exhaled nitric oxide and methacholine challenge testing was conducted from December 1, 2004, through November 30, 2005. Clinical records were extracted. Patients with no documented follow-up were contacted by telephone and administered a questionnaire. RESULTS In 64 patients, ICS therapy was started or the current ICS dose increased. Forty-one patients had elevated exhaled nitric oxide levels (defined as >or=35 ppb), 36 (88%) of whom had significant improvement in their chronic cough (likelihood ratio of a positive response, 4.9; 95% confidence interval, 2.2-10.9). Twenty-three patients with exhaled nitric oxide levels in the reference range were also prescribed ICS, and only 2 had cough improvement (likelihood ratio of a negative response, 0.07; 95% confidence interval, 0.02-0.25). Patients had documented follow-up that ranged from 4 weeks to 16 months. A cutoff of 38 ppb was found to best differentiate ICS responders and nonresponders. CONCLUSIONS Measurement of exhaled nitric oxide accurately predicted response to ICS therapy for chronic cough. Patients with a positive exhaled nitric oxide test result had a strong likelihood of response to ICS, whereas a negative exhaled nitric oxide test result indicated an unlikely response to ICS. This finding may potentially have an impact on how patients with chronic cough are evaluated and treated.
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Affiliation(s)
- Peter Y Hahn
- Division of Pulmonary and Critical Care Medicine, Mayo Clinic, 200 First St SW, Rochester, MN 55905, USA.
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159
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Kovesi T, Kulka R, Dales R. Exhaled nitric oxide concentration is affected by age, height, and race in healthy 9- to 12-year-old children. Chest 2007; 133:169-75. [PMID: 17925422 DOI: 10.1378/chest.07-1177] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
BACKGROUND The fractional concentration of exhaled nitric oxide (Feno) is a useful indicator of airway inflammation in children and adults with asthma. METHODS We determined the range of Feno concentrations and the factors affecting it in a large sample of healthy school children attending grades 4 through 6, in Windsor, ON, Canada. RESULTS Feno was measured in 657 children between 9.1 and 12.9 years of age. The range of Feno concentrations in healthy school children was 12.7 parts per billion (ppb) [95% confidence interval (CI), 11.8 to 13.7 ppb] in whites and 22.8 ppb [95% CI, 17.9 to 27.7 ppb] in Asian-Canadian children (p < 0.001). Feno values also appeared to be higher in African-Canadian children than in whites, although the CI was wide because of the small number of African-Canadian children sampled. Feno rose slightly but significantly with age (p = 0.007) and with height (p = 0.023). Body mass index and gender did not significantly alter the measured Feno. FVC had a nonsignificant effect on Feno. Participation in physical activity during the same day had a borderline-significant effect on measured Feno, but a reported history of a respiratory tract infection in the preceding 2 weeks did not. CONCLUSIONS Feno concentrations in healthy school-aged children appeared to be affected by race, and, to a lesser extent, by age and height. These factors should be taken into consideration when interpreting clinical results.
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Affiliation(s)
- Thomas Kovesi
- Department of Pediatrics, Children's Hospital of Eastern Ontario, 401 Smyth Rd, Ottawa, ON, Canada K1H 8L1.
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160
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Fortuna AM, Feixas T, Casan P. [Measurement of fraction of exhaled nitric oxide with the portable NIOX-MINO monitor in healthy adults]. Arch Bronconeumol 2007; 43:176-9. [PMID: 17386196 DOI: 10.1016/s1579-2129(07)60044-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Measurement of the fraction of exhaled nitric oxide (FENO) provides a noninvasive way to monitor asthma treatment in clinical practice. The aim of this study was to determine FENO reference values for measurements recorded with the portable NIOX MINO monitor in a group of healthy volunteers. We also assessed the association between values recorded by the portable monitor and the N-6008 chemiluminescence analyzer used in our pulmonary function laboratory. The FENO values obtained with the portable monitor were consistently higher than those recorded by the N-6008 analyzer; the cutoff value for the portable monitor was 34 ppb (mean + 2 SD). We detected a direct correlation (r=0.92) between the FENO measurements recorded by the 2 monitors (P=.001). The following equation expresses the relationship between measurements from the 2 devices: FENO(NIOX MINO) = 10 + [1.5 FENO(N-6008)]. We did not observe statistically significant correlations between FENO measurements and age, sex, body mass index, or spirometry.
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Affiliation(s)
- Ana María Fortuna
- Unidad de Función Pulmonar, Departamento de Neumología, Hospital de la Santa Creu i Sant Pau, Facultad de Medicina, Universidad Autónoma de Barcelona, Barcelona, España
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161
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Brindicci C, Ito K, Barnes PJ, Kharitonov SA. Differential flow analysis of exhaled nitric oxide in patients with asthma of differing severity. Chest 2007; 131:1353-62. [PMID: 17494785 DOI: 10.1378/chest.06-2531] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
BACKGROUND The majority of asthmatic patients achieve control of their illness; others do not. It is therefore crucial to validate/develop strategies that help the clinician monitor the disease, improving the response to treatment. METHODS We have quantified the inflammation in central and peripheral airways by measuring exhaled nitric oxide (NO) at multiple exhalation flows in 56 asthmatics at different levels of severity (mild, n = 10; moderate stable, n = 17; moderate during exacerbation, n = 11; severe, n = 18, 7 of whom were receiving oral corticosteroids) and 18 healthy control subjects. The reproducibility of the measurement was also assessed. RESULTS Bronchial NO (Jno) in patients with mild asthma (2,363 +/- 330 pL/s) [mean +/- SD] was higher than in patients with moderate stable asthma (1,300 +/- 59 pL/s, p < 0.0005), in patients with severe asthma receiving inhaled corticosteroids (ICS) [1,015 +/- 67 pL/s, p < 0.0005], and healthy control subjects (721 +/- 22 pL/s, p < 0.0001). There were no differences between Jno in patients with mild asthma compared to patients with severe asthma receiving ICS and oral corticosteroids (2,225 +/- 246 pL/s). Patients with exacerbations showed a higher Jno (3,475 +/- 368.9 pL/s, p < 0.05) compared to the other groups. Alveolar NO was higher in patients with severe asthma receiving oral corticosteroids (3.0 +/- 0.1 parts per billion [ppb], p < 0.0001) than in the other groups but was not significantly higher than in patients with moderate asthma during exacerbation (2.8 +/- 0.3 ppb). No differences were seen in NO diffusion levels between the different asthma groups. All the measurements were highly reproducible and free of day-to-day and diurnal variations. CONCLUSIONS Differential flow analysis of exhaled NO provides additional information about the site of inflammation in asthma and may be useful in assessing the response of peripheral inflammation to therapy.
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Affiliation(s)
- Caterina Brindicci
- Section of Airway Disease, National Heart and Lung Institute, Imperial College, Dovehouse Street, London, UK
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162
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Shaw DE, Berry MA, Thomas M, Green RH, Brightling CE, Wardlaw AJ, Pavord ID. The use of exhaled nitric oxide to guide asthma management: a randomized controlled trial. Am J Respir Crit Care Med 2007; 176:231-7. [PMID: 17496226 DOI: 10.1164/rccm.200610-1427oc] [Citation(s) in RCA: 241] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE Current asthma guidelines recommend adjusting antiinflammatory treatment on the basis of the results of lung function tests and symptom assessment, neither of which are closely associated with airway inflammation. OBJECTIVES We tested the hypothesis that titrating corticosteroid dose using the concentration of exhaled nitric oxide in exhaled breath (Fe(NO)) results in fewer asthma exacerbations and more efficient use of corticosteroids, when compared with traditional management. METHODS One hundred eighteen participants with a primary care diagnosis of asthma were randomized to a single-blind trial of corticosteroid therapy based on either Fe(NO) measurements (n = 58) or British Thoracic Society guidelines (n = 60). Participants were assessed monthly for 4 months and then every 2 months for a further 8 months. The primary outcome was the number of severe asthma exacerbations. Analyses were by intention to treat. MEASUREMENTS AND MAIN RESULTS The estimated mean (SD) exacerbation frequency was 0.33 per patient per year (0.69) in the Fe(NO) group and 0.42 (0.79) in the control group (mean difference, -21%; 95% confidence interval [CI], -57 to 43%; p = 0.43). Overall the Fe(NO) group used 11% more inhaled corticosteroid (95% CI, -17 to 42%; p = 0.40), although the final daily dose of inhaled corticosteroid was lower in the Fe(NO) group (557 vs. 895 microg; mean difference, 338 microg; 95% CI, -640 to -37; p = 0.028). CONCLUSIONS An asthma treatment strategy based on the measurement of exhaled nitric oxide did not result in a large reduction in asthma exacerbations or in the total amount of inhaled corticosteroid therapy used over 12 mo, when compared with current asthma guidelines. Clinical trial registered with www.controlled-trials.com (ISRCTN08067387).
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Affiliation(s)
- Dominick E Shaw
- Institute for Lung Health, Department of Respiratory Medicine and Thoracic Surgery, Glenfield Hospital, Leicester, United Kingdom
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163
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Travers J, Marsh S, Aldington S, Williams M, Shirtcliffe P, Pritchard A, Weatherall M, Beasley R. Reference ranges for exhaled nitric oxide derived from a random community survey of adults. Am J Respir Crit Care Med 2007; 176:238-42. [PMID: 17478616 DOI: 10.1164/rccm.200609-1346oc] [Citation(s) in RCA: 156] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE Measurement of the fraction of nitric oxide in exhaled breath (Fe(NO)) has been proposed as a noninvasive marker of airway inflammation. Before the widespread use of this test, there is a need to develop reference ranges to allow clinicians to interpret Fe(NO) measurements. OBJECTIVES To derive reference ranges for Fe(NO) and to determine which factors in health and disease influence Fe(NO) levels. METHODS Subjects aged between 25 and 75 years were drawn from a random sample of the predominantly white population of Wellington, New Zealand. MEASUREMENTS AND MAIN RESULTS Fe(NO) was measured using an online nitric oxide monitor in accordance with international guidelines. A detailed respiratory questionnaire and pulmonary function tests were performed. The geometric mean Fe(NO) was 17.9 parts per billion (ppb) with a 90% confidence interval for an individual prediction (reference range) for normal subjects of 7.8 to 41.1 ppb. Sex, atopy, and smoking status significantly affected Fe(NO) levels, and several reference ranges are presented adjusting for these factors. Asthma and allergic rhinitis were associated with higher Fe(NO). Measurement of Fe(NO) had poor discriminant ability to identify steroid-naive subjects with asthma. CONCLUSIONS The reference ranges presented may be used to assist in the interpretation of Fe(NO) measurements in white adults.
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Affiliation(s)
- Justin Travers
- Medical Research Institute of New Zealand, Wellington, New Zealand
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164
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Puthucheary ZA, Liu J, Bennett M, Trytko B, Chow S, Thomas PS. Exhaled nitric oxide is decreased by exposure to the hyperbaric oxygen therapy environment. Mediators Inflamm 2007; 2006:72620. [PMID: 17392577 PMCID: PMC1657071 DOI: 10.1155/mi/2006/72620] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Exhaled nitric oxide (eNO) detects airway inflammation. Hyperbaric oxygen therapy (HBOT)
is used for tissue hypoxia, but can cause lung damage. We measured eNO following
inhalation of oxygen at different tensions and pressures. Methods. Part 1, eNO was
measured before and after HBOT. Part 2, normal subjects breathed 40% oxygen. Results.
Baseline eNO levels in patients prior to HBOT exposure were significantly higher than in
normal subjects (P < .05). After HBOT, eNO significantly decreased in patients (15.4 ± 2.0 versus 4.4 ± 0.5 ppb, P < .001), but not in normal subjects, after either 100% O2 at increased pressure
or 40% oxygen, 1 ATA. In an in vitro study, nitrate/nitrite release decreased after 90 minutes
HBOT in airway epithelial (A549) cells. Conclusion. HBO exposure causes a fall in eNO.
Inducible nitric oxide synthase (iNOS) may cause elevated eNO in patients secondary to
inflammation, and inhibition of iNOS may be the mechanism of the reduction of eNO seen
with HBOT.
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Affiliation(s)
- Zudin A. Puthucheary
- UNSW and Department of Respiratory Medicine, Faculty of Medicine, Prince of Wales Hospital, Randwick, NSW 2031, Australia
| | - Jia Liu
- UNSW and Department of Respiratory Medicine, Faculty of Medicine, Prince of Wales Hospital, Randwick, NSW 2031, Australia
| | - Michael Bennett
- Hyperbaric Unit, Prince of Wales Hospital, Randwick, NSW 2031, Australia
| | - Barbara Trytko
- Hyperbaric Unit, Prince of Wales Hospital, Randwick, NSW 2031, Australia
| | - Sharron Chow
- UNSW and Department of Respiratory Medicine, Faculty of Medicine, Prince of Wales Hospital, Randwick, NSW 2031, Australia
| | - Paul S. Thomas
- UNSW and Department of Respiratory Medicine, Faculty of Medicine, Prince of Wales Hospital, Randwick, NSW 2031, Australia
- *Paul S. Thomas:
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165
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María Fortuna A, Feixas T, Casan P. Determinación de óxido nítrico en aire espirado (FENO) mediante un equipo portátil (NIOX-MINO® Aerocrine) en población sana. Arch Bronconeumol 2007. [DOI: 10.1157/13099536] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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166
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Gill M, Graff GR, Adler AJ, Dweik RA. Validation study of fractional exhaled nitric oxide measurements using a handheld monitoring device. J Asthma 2007; 43:731-4. [PMID: 17169823 DOI: 10.1080/02770900601031045] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
We tested reproducibility of exhaled nitric oxide (FE(NO)) and inter-operator handling when measured with a handheld device, NIOX MINO. We enrolled 20 volunteers using a priori goals of acceptable reproducibility to be mean within-subject standard deviation less than 3 parts per billion (ppb) for FE(NO) measurements less than 30 ppb, and mean coefficient of variation less than 10% for FE(NO) measurements more than 30 ppb. Seventeen subjects with measurements less than 30 ppb displayed a mean standard deviation of 1.15, and 3 subjects with FE(NO) more than 30 ppb had a mean coefficient of variation of 2.4%. We conclude that NIOX MINO demonstrates excellent reproducibility for all ranges of FE(NO).
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Affiliation(s)
- Michelle Gill
- The Department of Emergency Medicine, Loma Linda University School of Medicine, 11234 Anderson Street, Loma Linda, CA 92354, USA.
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167
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Chipps BE, Harder JM. Targeted interventions for difficult-to-treat asthma. Expert Opin Ther Targets 2007; 11:11-20. [PMID: 17150031 DOI: 10.1517/14728222.11.1.11] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Chronic persistent asthma has a significant burden in terms of healthcare-related expenses, decreased productivity and reduced quality of life for patients. Currently available guideline-directed therapy can control the majority of patients, but roughly one-third of patients will require additional care. This article reviews the barriers that hinder the ability of practitioners and patients to gain and maintain control of asthma, including inaccurate assessment measures, variability in patient response, and poor adherence. Strategies aimed at controlling difficult-to-treat disease, such as the use of biomarkers to assess control, are discussed. Newer and developing therapies that cater to specific types of asthmatic patients and may lead to improved outcomes in those patients for whom standard care is insufficient are also looked at.
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Affiliation(s)
- Bradley E Chipps
- Capital Allergy & Respiratory Disease Center, Sacramento, CA 95819, USA.
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168
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Stark H, Purokivi M, Kiviranta J, Randell J, Tukiainen H. Short-term and seasonal variations of exhaled and nasal NO in healthy subjects. Respir Med 2007; 101:265-71. [PMID: 16797173 DOI: 10.1016/j.rmed.2006.05.009] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2005] [Revised: 04/18/2006] [Accepted: 05/11/2006] [Indexed: 11/16/2022]
Abstract
Nitric oxide (NO) is an important biological mediator with a variety of cellular and tissue functions. Fractional exhaled (FE(NO)) and nasal NO (FN(NO)) are known to be altered in several respiratory tract disease and disorders. However, there are rather few studies into the reproducibility of FE(NO) or FN(NO) measurements in healthy subjects. The aim of this study was to examine both short- and long-term variations of FE(NO) and FN(NO). In addition to intraday, day-to-day and week-to-week variations, the seasonal variation was assessed. The data revealed that FE(NO) and FN(NO) levels were lower in the mornings compared to the afternoon values. There were clinically significant correlations in day-to-day (morning values 121.4+/-37.5 vs. 119.8+/-29.6, r=0.868, P=0.000), week-to-week (morning values 121.4+/-37.5 vs. 128.0+/-32.1, r=0.637, P=0.000) and seasonal (winter 133.5+/-29.7, summer 138.1+/-47.6, autumn 121.4+/-37.5, r=0.624, P=0.000) values of FN(NO). Day-to-day (morning values 14.6+/-6.7 vs. 14.2+/-5.1, r=0.784, P=0.000) week-to-week (morning values 14.6+/-6.7 vs. 15.4+/-7.3, r=0.738, P=0.000) and seasonal (autumn 14.6+/-7.2, winter 16.6+/-6.4, summer 17.4+/-8.0, r=0.709, P=0.000) levels of FE(NO) were also highly reproducible. Serial FE(NO) and FN(NO) measurements can be used in the monitoring of respiratory tract inflammation. Due to the diurnal variation of FE(NO) and FN(NO,) in long-term follow-up the measurements should be performed at the same time of day.
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Affiliation(s)
- Harri Stark
- Department of Respiratory Medicine, Kuopio University Hospital, FIN 70211 Kuopio, Finland.
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169
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Abstract
Assessing airway and lung inflammation is important for investigating the underlying mechanisms of asthma and COPD. Yet these cannot be measured directly in clinical research and practice because of the difficulties in monitoring inflammation. Noninvasive monitoring may assist in early recognition of asthma and COPD, assessment of its severity, and response to treatment, especially during disease exacerbations. There is increasing evidence that breath analysis may have an important place in clinical management of asthma and COPD. The article reviews the role of current noninvasive measurements of exhaled gases, such as nitric oxide (NO), inflammatory markers in exhaled breath condensate (EBC), and exhaled breath temperature, as well as novel methods in monitoring and management of asthma and COPD.
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170
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McGill C, Malik G, Turner SW. Validation of a hand-held exhaled nitric oxide analyzer for use in children. Pediatr Pulmonol 2006; 41:1053-7. [PMID: 16871592 DOI: 10.1002/ppul.20491] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Measurements of exhaled nitric oxide (FE(NO)) may be useful in the diagnosis and management of asthma in children. A new hand-held device (MINO, Aerocrine) for measuring FE(NO) has been marketed but has not been validated in a pediatric population. The objective is to validate the MINO against the NIOX analyzer. This was a randomized cross-over study where FE(NO) was measured in a single assessment using the MINO and NIOX. Children were recruited from a respiratory clinic and had six attempts to provide a FE(NO) measurement with each analyzer. Fifty-five children were enrolled, 33 boys, median age 9 years. A mean FE(NO) value was obtained in 39 children with MINO and 44 with NIOX. Paired mean FE(NO) values were obtained in 34 children and the values were higher for the NIOX (mean difference 3.9 ppb limits of agreement -1.1, 8.9). The differences between analyzers became greater at higher FE(NO) values. The first FE(NO) value using the MINO was 24 ppb and the mean of all FE(NO) values using the MINO was 27 ppb (difference not significant). Exhaled NO values were comparable between the two analyzers although there was greater consistency at lower values. The findings of the study do not contradict the manufacturer's recommendation that only one FE(NO) value is required with the MINO, however, we suggest that the mean of at least two values should be reported in children.
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Affiliation(s)
- Claire McGill
- Department of Child Health, University of Aberdeen, Aberdeen, United Kingdom
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171
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Taylor DR, Pijnenburg MW, Smith AD, De Jongste JC. Exhaled nitric oxide measurements: clinical application and interpretation. Thorax 2006; 61:817-27. [PMID: 16936238 PMCID: PMC2117092 DOI: 10.1136/thx.2005.056093] [Citation(s) in RCA: 346] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
The use of exhaled nitric oxide measurements (F(E)NO) in clinical practice is now coming of age. There are a number of theoretical and practical factors which have brought this about. Firstly, F(E)NO is a good surrogate marker for eosinophilic airway inflammation. High F(E)NO levels may be used to distinguish eosinophilic from non-eosinophilic pathologies. This information complements conventional pulmonary function testing in the assessment of patients with non-specific respiratory symptoms. Secondly, eosinophilic airway inflammation is steroid responsive. There are now sufficient data to justify the claim that F(E)NO measurements may be used successfully to identify and monitor steroid response as well as steroid requirements in the diagnosis and management of airways disease. F(E)NO measurements are also helpful in identifying patients who do/do not require ongoing treatment with inhaled steroids. Thirdly, portable nitric oxide analysers are now available, making routine testing a practical possibility. However, a number of issues still need to be resolved, including the diagnostic role of F(E)NO in preschool children and the use of reference values versus individual F(E)NO profiles in managing patients with difficult or severe asthma.
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Affiliation(s)
- D R Taylor
- Department of Medical and Surgical Sciences, Dunedin School of Medicine, University of Otago, P O Box 913, Dunedin, New Zealand.
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172
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Fritsch M, Uxa S, Horak F, Putschoegl B, Dehlink E, Szepfalusi Z, Frischer T. Exhaled nitric oxide in the management of childhood asthma: a prospective 6-months study. Pediatr Pulmonol 2006; 41:855-62. [PMID: 16850457 DOI: 10.1002/ppul.20455] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Fractional exhaled nitric oxide (FeNO) is elevated in asthma and reflects eosinophilic airway inflammation. The aim of this prospective, randomized, single-blind study was to examine whether the inclusion of repeated FeNO measurements into asthma monitoring leads to an improvement in asthma outcome. Forty-seven children with mild to moderate asthma were allocated to a FeNO group (n = 22) and to a control group (n = 25). In the FeNO group therapy was based on symptoms, beta-agonist use, lung function, and FeNO whereas in the control group therapy was based on symptoms, beta-agonist use and lung function only. Patients performed five visits in 6 weeks intervals. Frequency of respiratory symptoms, beta-agonist use, FEV(1)% predicted and the frequency of exacerbations were similar between groups. Patients in the FeNO group received higher doses of inhaled corticosteroids (ICS) (control group: median (interquartile range): 241 microg (26-607 microg); FeNo group: 316 microg (200-500 microg) and had significantly higher MEF(50)% predicted (control group: median (interquartile range): 68.5% (55.8-83.1%); FeNO group: 83.2% (62.9%-98.3%). At a cut-off point of 22.9 ppb FeNO the best predictive value for exacerbations with a sensitivity of 80% and specificity of 60% was found. Significant relationships were observed between FeNO and dose of ICS (beta = -8.77; P < 0.002), beta-agonist use 2 weeks prior to a visit (beta = 0.11; P < 0.05), asthma symptoms (beta = 0.02; P < 0.0001), and bronchial hyperresponsiveness (beta = 0.04; P = 0.02). In conclusion, FeNO was related to important markers of asthma control. A therapy regimen aimed at lowering FeNO in children with asthma improved parameters of small airway function, but was not able to improve clinical markers of asthma control.
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Affiliation(s)
- Maria Fritsch
- Department of General Paediatrics, University Children's Hospital, Vienna, Austria
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173
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Gelb AF, Flynn Taylor C, Shinar CM, Gutierrez C, Zamel N. Role of spirometry and exhaled nitric oxide to predict exacerbations in treated asthmatics. Chest 2006; 129:1492-9. [PMID: 16778266 DOI: 10.1378/chest.129.6.1492] [Citation(s) in RCA: 129] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
OBJECTIVE To evaluate the complementary roles of exhaled nitric oxide (NO) and spirometry to predict asthma exacerbations requiring one or more tapering courses of systemic corticosteroids. METHODS We prospectively studied 44 nonsmoking asthmatics (24 women) aged 51 +/- 21 years (mean +/- SD) who were clinically stable for 6 weeks and receiving 250 mug of fluticasone/50 mug of salmeterol or equivalent for 3 years. Total exhaled NO (FENO), small airway/alveolar NO (CANO), large airway NO flux (J'awNO), and spirometry were measured. RESULTS Baseline FEV(1) was 2.1 +/- 0.7 L, 70 +/- 20% of predicted after 180 mug of albuterol. Twenty-two of 44 asthmatics had one or more exacerbations over 18 months, 16 of 22 asthmatics had two exacerbations, and 6 of 22 asthmatics were hospitalized, including 1 asthmatic with near-fatal asthma. When baseline FEV(1) was </= 76% predicted, exacerbations occurred in 20 of 31 asthmatics (65%). If baseline FEV(1) was > 76% of predicted, exacerbations occurred only in 2 of 13 asthmatics (15%) [p = 0.003, chi(2)]. Using a receiver operating characteristic (ROC) curve for first exacerbation, the area under the curve was 0.67 with cutoff FEV(1) of 76% of predicted (sensitivity, 0.91; specificity, 0.50; positive predictive value, 0.65; negative predictive value, 0.85; positive likelihood ratio [LR(+)], 1.8; negative likelihood ratio [LR(-)], 0.18). When baseline FENO was >/= 28 parts per billion (ppb), exacerbations occurred in 13 of 17 asthmatics (76%); if baseline FENO was < 28 ppb, exacerbations occurred in only 9 of 27 asthmatics (33%) [p = 0.005, chi(2)]. Using the ROC curve for first exacerbation, the area under the curve was 0.71 with FENO cutoff point of 28 ppb (sensitivity, 0.59; specificity, 0.82; positive predictive value, 0.77; negative predictive value, 0.87; LR(+), 3.3; LR(-), 0.5). Independent of baseline FEV(1), FENO >/= 28 ppb increased the relative risk (RR) for exacerbation by 3.4 (95% confidence interval [CI], 1.3 to 9.1; Mantel-Haenszel, p = 0.007). An abnormal increase in CANO increased RR by 3.0 (95% CI, 0.9 to 9.9; p = 0.04), and abnormal J'awNO increased RR by 2.4 (95% CI, 1.0 to 5.6; p = 0.04). Independent of baseline FENO, FEV(1) </= 76% predicted increased RR by 1.7 (95% CI, 1.0 to 2.7; p = 0.02). Combined baseline FENO >/= 28 ppb and FEV(1) </= 76% of predicted identified 13 stable asthmatics with 85% probability for future exacerbation, whereas 9 asthmatics with FENO < 28 ppb and FEV(1) > 76% of predicted had a 0% probability of exacerbation. CONCLUSION Combining FENO and FEV(1) percentage of predicted can stratify risk for asthma exacerbation.
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Affiliation(s)
- Arthur F Gelb
- Lakewood Regional Medical Center, Lakewood, CA 90712, USA.
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174
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Malmberg LP, Petäys T, Haahtela T, Laatikainen T, Jousilahti P, Vartiainen E, Mäkelä MJ. Exhaled nitric oxide in healthy nonatopic school-age children: determinants and height-adjusted reference values. Pediatr Pulmonol 2006; 41:635-42. [PMID: 16703576 DOI: 10.1002/ppul.20417] [Citation(s) in RCA: 119] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Exhaled nitric oxide (FENO) was proposed as a marker of airway inflammation, but data about FENO in healthy children measured with standardized methods are so far limited. In order to assess the determinants of FENO in healthy children, we investigated a population-based sample of school-age children (n = 276) with a questionnaire, skin-prick tests, spirometry, and the measurement of FENO. The FENO of 114 nonatopic and nonsmoking children considered healthy were analyzed with stepwise multiple regression analysis, which showed significant associations with age, standing height, weight, and body surface area, but not with gender. Height was found to be the best independent variable for the regression equation for FENO, which on average showed an increase in the height range of 120-180 cm from 7 to 14 ppb. In the random sample of children, increased FENO was associated with atopy (odds ratio, 9.0; 95% confidence interval, 3.9-21.1; P < 0.0001), and significantly with allergic rhinitis and atopic dermatitis, but not with asthma. Respiratory symptom-free children with skin-prick test positivity had significantly higher FENO than healthy nonatopic subjects. We conclude that height is the best determinant of FENO in healthy children. Due to the strong effect of atopy, FENO data should not be interpreted without knowing the atopic status of the child. The present reference values of FENO may serve in clinical assessments for measuring airway inflammation in children.
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Affiliation(s)
- L P Malmberg
- Department of Allergy, Helsinki University Central Hospital, Helsinki, Finland.
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175
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Choi J, Hoffman LA, Rodway GW, Sethi JM. Markers of lung disease in exhaled breath: nitric oxide. Biol Res Nurs 2006; 7:241-55. [PMID: 16581895 DOI: 10.1177/1099800405286131] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Management of airway inflammation requires proper monitoring and treatment to improve long-term outcomes. However, achieving this goal is difficult, as current methods have limitations. Although nitric oxide (NO) was first identified 200 years ago, its physiological importance was not recognized until the early 1980s. Many studies have established the role of NO as an essential messenger molecule in body systems. In addition, studies have demonstrated a significant relationship between changes in exhaled NO levels and other markers of airway inflammation. The technique used to measure NO in exhaled breath is noninvasive, reproducible, sensitive, and easy to perform. Consequently, there is growing interest in the use of exhaled NO in the management of asthma and other pulmonary conditions. The purpose of this review is to promote a basic understanding of the physiologic actions of NO, measurement techniques, and ways that research findings might translate to future application in clinical practice. Specifically, the article will review the role of exhaled NO in regard to its historical background, mechanisms of action, measurement techniques, and implications for clinical practice and research.
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Affiliation(s)
- JiYeon Choi
- University of Pittsburgh School of Nursing, Pennsylvania 15261, USA.
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176
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Abstract
Exhaled NO (FENO) is a non-invasive, validated marker for asthmatic airway inflammation. Recently, a new hand-held NO-analyzer has been developed which makes it possible to monitor FENO at home. We assessed feasibility and analyzed variability of daily FENO home measurements. Twenty-one asthmatics (mean age 14.5 yr; range 8-25 yr) participated. Nineteen used a stable dose of inhaled corticosteroids and all of them were in a stable clinical condition. FENO was measured twice daily for 14 consecutive days. Measurements and symptom scores were recorded on a smart card in the analyzer. Symptom score items included well-being, wheeze, activity, and nocturnal symptoms. Measurements showed a success rate of 93%. We found a significant diurnal variation in FENO with geometric mean morning levels 14% higher than evening levels (95% CI: 4%-25%; p = 0.013). Individual subjects showed marked fluctuation of FENO. The mean intrasubject coefficient of variation of FENO was 40% for morning and 36% for evening values. FENO and cumulative symptom scores did not correlate. Home FENO measurements are feasible, and offer the possibility to asses airway inflammation on a daily basis. Further study is needed to interpret and evaluate possible benefits of FENO home monitoring.
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Affiliation(s)
- Mariëlle W Pijnenburg
- Department of Pediatric Respiratory Medicine, Erasmus MC-Sophia Children's Hospital, Erasmus University Medical Centre, Rotterdam, The Netherlands.
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177
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Ehrs PO, Sundblad BM, Larsson K. Quality of life and inflammatory markers in mild asthma. Chest 2006; 129:624-31. [PMID: 16537860 DOI: 10.1378/chest.129.3.624] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
STUDY OBJECTIVES The aim of this study was to explore the relationship between quality of life and measures of asthma, such as lung function, reversibility to bronchodilation, exhaled nitric oxide (NO), and bronchial responsiveness to direct and indirect stimulus in patients with mild asthma in a primary care setting. PATIENTS AND MEASUREMENTS Seventy-seven asthmatic patients not treated with glucocorticosteroids completed the Asthma Quality of Life Questionnaire. Spirometry was performed before and after bronchodilation, and bronchial challenges with methacholine and eucapnic dry air hyperventilation were conducted on separate days. NO in exhaled air and serum IgE were also analyzed. RESULTS We found no correlation between quality of life and any of the other parameters. There was a significant covariation between exhaled NO and bronchial responsiveness to methacholine and dry air, and also between FEV(1) (percentage of predicted) and reversibility to a bronchodilator. The levels of exhaled NO were higher in the asthmatic subjects with atopy than in the nonatopic asthmatics. CONCLUSIONS The measures used in our study do not reflect health-related quality of life in subjects with mild asthma. We conclude that in the clinical situation, quality of life and other measures of asthma provide complementary information.
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Affiliation(s)
- Per-Olof Ehrs
- Unit of Lung and Allergy Research, National Institute of Environmental Medicine, Karolinska Institutet, SE-171 77 Stockholm, Sweden.
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178
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Alving K, Janson C, Nordvall L. Performance of a new hand-held device for exhaled nitric oxide measurement in adults and children. Respir Res 2006; 7:67. [PMID: 16626491 PMCID: PMC1462993 DOI: 10.1186/1465-9921-7-67] [Citation(s) in RCA: 148] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2005] [Accepted: 04/20/2006] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Exhaled nitric oxide (NO) measurement has been shown to be a valuable tool in the management of patients with asthma. Up to now, most measurements have been done with stationary, chemiluminescence-based NO analysers, which are not suitable for the primary health care setting. A hand-held NO analyser which simplifies the measurement would be of value both in specialized and primary health care. In this study, the performance of a new electrochemical hand-held device for exhaled NO measurements (NIOX MINO) was compared with a standard stationary chemiluminescence unit (NIOX). METHODS A total of 71 subjects (6-60 years; 36 males), both healthy controls and atopic patients with and without asthma were included. The mean of three approved exhalations (50 ml/s) in each device, and the first approved measurement in the hand-held device, were compared with regard to NO readings (Bland-Altman plots), measurement feasibility (success rate with 6 attempts) and repeatability (intrasubject SD). RESULTS Success rate was high (> or = 84%) in both devices for both adults and children. The subjects represented a FENO range of 8-147 parts per billion (ppb). When comparing the mean of three measurements (n = 61), the median of the intrasubject difference in exhaled NO for the two devices was -1.2 ppb; thus generally the hand-held device gave slightly higher readings. The Bland-Altman plot shows that the 95% limits of agreement were -9.8 and 8.0 ppb. The intrasubject median difference between the NIOX and the first approved measurement in the NIOX MINO was -2.0 ppb, and limits of agreement were -13.2 and 10.2 ppb. The median repeatability for NIOX and NIOX MINO were 1.1 and 1.2 ppb, respectively. CONCLUSION The hand-held device (NIOX MINO) and the stationary system (NIOX) are in clinically acceptable agreement both when the mean of three measurements and the first approved measurement (NIOX MINO) is used. The hand-held device shows good repeatability, and it can be used successfully on adults and most children. The new hand-held device will enable the introduction of exhaled NO measurements into the primary health care.
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Affiliation(s)
- K Alving
- Department of Physiology and Pharmacology, Karolinska Institutet, SE-17177 Stockholm, Sweden
| | - C Janson
- Department of Medical Sciences, Uppsala University, Uppsala, Sweden
| | - L Nordvall
- Department of Women's and Children's Health, Uppsala University, Uppsala, Sweden
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179
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Barnes PJ, Chowdhury B, Kharitonov SA, Magnussen H, Page CP, Postma D, Saetta M. Pulmonary biomarkers in chronic obstructive pulmonary disease. Am J Respir Crit Care Med 2006; 174:6-14. [PMID: 16556692 DOI: 10.1164/rccm.200510-1659pp] [Citation(s) in RCA: 162] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
There has been increasing interest in using pulmonary biomarkers to understand and monitor the inflammation in the respiratory tract of patients with chronic obstructive pulmonary disease (COPD). In this Pulmonary Perspective we discuss the merits of the various approaches by reviewing the current literature on pulmonary biomarkers in COPD and underscore the need for more systematic studies in the future. Bronchial biopsies and bronchoalveolar lavage provide valuable information about inflammatory cells and mediators, but are invasive, so that repeated measurements have to be very limited in assessing any interventions. Induced sputum has provided considerable information about the inflammatory process, including mediators and proteinases in COPD, but selectively samples proximal airways and may not closely reflect distal inflammatory processes. Exhaled gases and breath condensate are noninvasive procedures, so repeated measurements are possible, but for some assays the variability is relatively high. There is relatively little information about how any of these biomarkers relate to other clinical outcomes, such as progression of the disease, severity of disease, clinical subtypes, or response to therapy. More information is also needed about the variability in these measurements. In the future, pulmonary biomarkers may be useful in predicting disease progression, indicating disease instability, and in predicting response to current therapies and novel therapies, many of which are now in development.
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Affiliation(s)
- Peter J Barnes
- National Heart and Lung Institute, Imperial College London, London, UK.
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180
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Taylor DR. Nitric oxide as a clinical guide for asthma management. J Allergy Clin Immunol 2006; 117:259-62. [PMID: 16461124 DOI: 10.1016/j.jaci.2005.11.010] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2005] [Revised: 11/07/2005] [Accepted: 11/07/2005] [Indexed: 11/16/2022]
Abstract
Asthma is a pathologically heterogeneous disease, and the phenotype is characterized by different types of airway inflammation. Exhaled nitric oxide (F(E)NO) measurements are a surrogate marker specific for eosinophilic airway inflammation. The latter is usually associated with steroid responsiveness, and hence, F(E)NO may be used to guide steroid requirements in certain clinical situations. High F(E)NO levels may be used to predict likely benefits with inhaled corticosteroid (ICS) therapy. Both high and low F(E)NO levels are prognostically significant when withdrawal of ICS treatment is being considered. Studies have shown that, just as for induced sputum, repeated F(E)NO measurements improve the cost-effectiveness of ICS therapy when used to guide dose requirements. In practice, F(E)NO measurements are useful in the management of severe or difficult asthma. High and low F(E)NO levels in symptomatic patients provide the clinician with information that enables active eosinophilic airway inflammation to be included or excluded. Either outcome is helpful in decision making. F(E)NO measurements complement the use of other tests in asthma, but more work is required to determine reference values and cut-points for appropriate interpretation.
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Affiliation(s)
- D Robin Taylor
- Department of Medicine, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand.
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181
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Boot JD, Panzner P, Diamant Z. A critical appraisal of methods used in early clinical development of novel drugs for the treatment of asthma. Pulm Pharmacol Ther 2006; 20:201-19. [PMID: 16584905 DOI: 10.1016/j.pupt.2006.02.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2006] [Revised: 02/06/2006] [Accepted: 02/14/2006] [Indexed: 11/16/2022]
Abstract
Asthma is a heterogeneous disorder characterized by chronic airway inflammation, hyperresponsiveness and remodeling. Being the hallmark of asthma, airway inflammation has become the most important target for therapeutic agents. Consequently, during the past decade various semi-and non-invasive methods have been explored to sample the airway inflammation in asthma. In this review, we provide a practical overview of the current status of various sampling techniques including sputum induction, exhaled breath analysis, and bronchoprovocation tests (BPTs). We focus on their applicability for monitoring in clinical practice and in intervention trials in asthma.
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Affiliation(s)
- J D Boot
- Centre for Human Drug Research, Zernikedreef 10, 2333 CL Leiden, The Netherlands
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182
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Buchvald F, Hermansen MN, Nielsen KG, Bisgaard H. Exhaled nitric oxide predicts exercise-induced bronchoconstriction in asthmatic school children. Chest 2005; 128:1964-7. [PMID: 16236842 DOI: 10.1378/chest.128.4.1964] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
BACKGROUND Exercise-induced bronchoconstriction (EIB) is of particular importance in children with asthma. It is an important measure of asthma control and should be monitored by exercise testing. However, exercise testing puts a large demand on health-care resources and is therefore not widely used in routine monitoring of pediatric asthma control. The fractional concentration of exhaled nitric oxide (FeNO) also reflects uncontrolled asthma. We hypothesized that FeNO may be used for prescreening of asthmatic children to exclude those with good asthma control unlikely to have EIB, thereby reducing the need for exercise testing. OBJECTIVE The aim of this study was to estimate the value of FeNO as a predictor of EIB in asthmatic children. METHODS Stable outpatient asthmatic school children performed standard exercise challenge tests and measurement of FeNO. RESULTS FeNO and response to a standardized submaximal exercise test on the treadmill were measured in 111 school children with asthma. EIB could be excluded with a probability of 90% in asthmatic children with FeNO levels < 20 parts per billion (ppb) without current inhaled corticosteroid treatment, and < 12 ppb in children with current inhaled corticosteroid treatment. CONCLUSION Measurement of FeNO is a simple, and time- and resource-efficient tool that may be used to screen for EIB testing and therefore optimizes the resources for exercise testing in pediatric asthma monitoring.
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Affiliation(s)
- Frederik Buchvald
- Danish Pediatric Asthma Centre, Department of Pediatrics, Copenhagen University Hospital, DK-2900 Gentofte, Niels Andersensvej 79, 2900 Hellerup, Denmark
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183
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Abstract
Delayed offline measurement of exhaled nitric oxide (eNO), although useful in environmental and clinical research, is limited by the instability of stored breath samples. The authors characterized sources of instability with the goal of minimizing them. Breath and other air samples were stored under various conditions, and NO levels were measured repeatedly over 1-7 d. Concentration change rates varied positively with temperature and negatively with initial NO level, thus "stable" levels reflected a balance of NO-adding and NO-removing processes. Storage under refrigeration for a standardized period of time can optimize offline eNO measurement, although samples at room temperature are effectively stable for several hours.
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Affiliation(s)
- William S Linn
- Environmental Health Service, Los Amigos Research and Education Institute, Downey, California, USA.
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184
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Vints AM, Oostveen E, Eeckhaut G, Smolders M, De Backer WA. Time-Dependent Effect of Nitrate-Rich Meals on Exhaled Nitric Oxide in Healthy Subjects. Chest 2005; 128:2465-70. [PMID: 16236910 DOI: 10.1378/chest.128.4.2465] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
BACKGROUND Exhaled nitric oxide (eNO) is a convenient noninvasive marker for airway inflammation in several pulmonary diseases. However, external factors such as nitrate-rich nutrition can affect the levels of eNO and thus compromise its diagnostic value. STUDY OBJECTIVES The objective of this investigation was to have a better understanding of the time-dependent effect of nitrate-rich meals on eNO in healthy subjects. STUDY DESIGN Forty-two healthy, nonsmoking volunteers (age range, 25 to 62 years) were recruited for the study. They had no recent respiratory tract infections and were free of pulmonary history, rhinitis, and atopic disorders. eNO was measured before, and 0.5, 2, 4, 12, 15, and 20 h after the intake of a nitrate-rich meal equivalent to 230 mg of nitrate. RESULTS The intake of a nitrate-rich meal increased eNO by 60% 2 h after the meal. Even after 15 h, the mean eNO value was still 22% higher than the baseline value. Only after 20 h did eNO return to the normal baseline level. CONCLUSION This finding stresses the importance of advising patients to avoid nitrate-rich nutrition at least 20 h before a scheduled measurement of eNO.
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Affiliation(s)
- Anne-Marie Vints
- Department of Respiratory Medicine, University Hospital Antwerp, Wilrijkstraat, 10, Edegem 2650, Belgium.
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185
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Hemmingsson T, Linnarsson D, Gambert R. Novel hand-held device for exhaled nitric oxide-analysis in research and clinical applications. J Clin Monit Comput 2005; 18:379-87. [PMID: 15957630 DOI: 10.1007/s10877-005-1158-z] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Changes in expired nitric oxide (NO) occur in airway inflammation and have proved to be important in the monitoring of inflammatory disease processes such as asthma. We set out to develop a novel hand-held NO-analyzer with a performance comparable to the present more costly and complex chemiluminescence instruments. The new device is based on a specially designed electrochemical sensor, where we have developed a novel sampling and analysis technology, compensating for the relatively slow response properties of the electrochemical sensor technique. A Lowest Detection Limit in NO-analysis from reference gas tests of less than 3 ppb and a response time of 15 seconds together with an average precision in human breath measurements of 1.4 ppb were obtained. We also show an agreement with the existing 'gold standard' FENO measurement technique, within 0.5 ppb in a group of 19 subjects together with a high linearity and accuracy compared to reference gases. The new analyzer enables affordable monitoring of inflammatory airway diseases in research and routine clinical practice.
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Affiliation(s)
- Tryggve Hemmingsson
- Sect. of Environmental Physiology, Dept. of Physiology and Pharmacology, Karolinska Institutet, SE-171 77 Stockholm, Sweden.
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186
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Napier E, Turner SW. Methodological issues related to exhaled nitric oxide measurement in children aged four to six years. Pediatr Pulmonol 2005; 40:97-104. [PMID: 15965893 DOI: 10.1002/ppul.20249] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
This study was designed to test five methodological issues related to measurement of fractional exhaled nitric oxide (FE(NO)) in children aged 4-6 years using commercially available apparatus. Participants attended two randomly selected schools. A respiratory questionnaire was completed. Measurements of FE(NO) were made on successive days, using a NIOX analyzer employing standard or modified methodologies. Ninety-one children participated in the study (mean age, 5.3 years; 46 boys). Using a standard methodology (n = 61), FE(NO) was successfully measured in 28 (46%) children, 1/12 aged 4 years, 12/25 aged 5 years, and 15/24 aged 6 years (trend test P = 0.01). On the first assessment, FE(NO) could be determined in more boys than girls (64% vs. 30%, respectively, P = 0.008), but this gender difference was not apparent on the second assessment. Exhaled NO was reproducible over a 24-hr period; the mean difference between repeated measurements of natural log (ln) FE(NO) was 0.016 parts per billion (ppb) (95% confidence limits, -0.479, 0.511), n = 20. Data from 35 assessments showed that values of FE(NO) did not alter over nine individual, successive measurements. Use of a modified methodology in 30 children increased success in obtaining FE(NO), but these values were unreliable. In conclusion, measurements of FE(NO) can be obtained in the majority of 5- and 6-year-old but not 4-year-old children. Exhaled NO measurements were reproducible over a 24-hr interval, and did not change over up to nine expiratory maneuvers in these young children.
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Affiliation(s)
- Edward Napier
- Department of Child Health, University of Aberdeen, Aberdeen, Scotland, UK
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187
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Shahid SK, Kharitonov SA, Wilson NM, Bush A, Barnes PJ. Exhaled 8-isoprostane in childhood asthma. Respir Res 2005; 6:79. [PMID: 16042771 PMCID: PMC1188076 DOI: 10.1186/1465-9921-6-79] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2005] [Accepted: 07/21/2005] [Indexed: 11/15/2022] Open
Abstract
Background Exhaled breath condensate (EBC) is a non-invasive method to assess airway inflammation and oxidative stress and may be useful in the assessment of childhood asthma. Methods Exhaled 8-isoprostane, a stable marker of oxidative stress, was measured in EBC, in children (5–17 years) with asthma (13 steroid-naïve and 12 inhaled steroid-treated) and 11 healthy control. Results Mean exhaled 8-isoprostane concentration was significantly elevated in steroid-naïve asthmatic children compared to healthy children 9.3 (SEM 1.7) vs. 3.8 (0.6) pg/ml, p < 0.01. Children on inhaled steroids also had significantly higher 8-isoprostane levels than those of normal subjects 6.7 (0.7) vs. 3.8 (0.6) pg/ml, p < 0.01. Steroid-naïve asthmatics had higher exhaled nitric oxide (eNO) than those of controls 28.5 (4.7) vs. 12.6 (1.5) ppb, p < 0.01. eNO in steroid-treated asthmatics was similar to control subjects 27.5(8.8) vs. 12.6(1.5) ppb. Exhaled 8-isoprostane did not correlate with duration of asthma, dose of inhaled steroids or eNO. Conclusion We conclude that 8-isoprostane is elevated in asthmatic children, indicating increased oxidative stress, and that this does not appear to be normalized by inhaled steroid therapy. This suggests that 8-isoprostane is a useful non-invasive measurement of oxidative stress in children and that antioxidant therapy may be useful in the future.
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Affiliation(s)
- Sukhbir K Shahid
- Section of Airway Disease, National Heart and Lung Institute, Imperial College London, London, UK
| | - Sergei A Kharitonov
- Section of Airway Disease, National Heart and Lung Institute, Imperial College London, London, UK
| | - Nicola M Wilson
- Department of Paediatrics, Royal Brompton Hospital, London, UK
| | - Andrew Bush
- Department of Paediatrics, Royal Brompton Hospital, London, UK
| | - Peter J Barnes
- Section of Airway Disease, National Heart and Lung Institute, Imperial College London, London, UK
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188
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Smith AD, Taylor DR. Is exhaled nitric oxide measurement a useful clinical test in asthma? Curr Opin Allergy Clin Immunol 2005; 5:49-56. [PMID: 15643344 DOI: 10.1097/00130832-200502000-00010] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
PURPOSE OF REVIEW Exhaled nitric oxide measurements (FENO) are easy to perform and are repeatable. Given the strong correlations between FENO and bronchial biopsy and induced sputum eosinophilia, as well as airway hyper-responsiveness, FENO may now be advocated as a surrogate for these tests in certain circumstances. They provide the opportunity to assess pathological rather than physiological changes in asthma. This review highlights recent advances in applying this technology to the diagnosis and ongoing assessment of asthma in the clinical and epidemiological settings. RECENT FINDINGS Epidemiological data confirm that whereas FENO measurements reflect the presence and severity of airway inflammation, levels do not correlate strongly with symptoms or lung function abnormalities. Although reference values and thresholds for an abnormal test still need to be agreed internationally, there are now sufficient data for clinicians to use the test meaningfully in clinical practice. Studies confirm the relatively high diagnostic accuracy of FENO measurements compared with conventional tests to distinguish asthma from nonasthma. Further, dose-response relationships for changes in FENO with inhaled steroids have been confirmed, and provide the basis for using FENO to assess asthma control and, potentially, to determine antiinflammatory treatment requirements. SUMMARY The measurement of FENO is evolving to provide a complementary role alongside existing pulmonary function tests. Further work is required to establish reference values and possibly prediction equations in relation to age and height. Its role in determining optimum steroid requirements in chronic asthma and to identify steroid responsiveness in chronic obstructive pulmonary disease are two important areas for future research.
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Affiliation(s)
- Andrew D Smith
- Respiratory Research Unit, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
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189
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Smith AD, Cowan JO, Brassett KP, Herbison GP, Taylor DR. Use of exhaled nitric oxide measurements to guide treatment in chronic asthma. N Engl J Med 2005; 352:2163-73. [PMID: 15914548 DOI: 10.1056/nejmoa043596] [Citation(s) in RCA: 734] [Impact Index Per Article: 38.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND International guidelines for the treatment of asthma recommend adjusting the dose of inhaled corticosteroids on the basis of symptoms, bronchodilator requirements, and the results of pulmonary-function tests. Measurements of the fraction of exhaled nitric oxide (FE(NO)) constitute a noninvasive marker that may be a useful alternative for the adjustment of inhaled-corticosteroid treatment. METHODS In a single-blind, placebo-controlled trial, we randomly assigned 97 patients with asthma who had been regularly receiving treatment with inhaled corticosteroids to have their corticosteroid dose adjusted, in a stepwise fashion, on the basis of either FE(NO) measurements or an algorithm based on conventional guidelines. After the optimal dose was determined (phase 1), patients were followed up for 12 months (phase 2). The primary outcome was the frequency of exacerbations of asthma; the secondary outcome was the mean daily dose of inhaled corticosteroid. RESULTS Forty-six patients in the FE(NO) group and 48 in the group whose asthma was treated according to conventional guidelines (the control group) completed the study. The final mean daily doses of fluticasone, the inhaled corticosteroid that was used, were 370 microg per day for the FE(NO) group (95 percent confidence interval, 263 to 477) and 641 microg per day for the control group (95 percent confidence interval, 526 to 756; P=0.003), a difference of 270 microg per day (95 percent confidence interval, 112 to 430). The rates of exacerbation were 0.49 episode per patient per year in the FE(NO) group (95 percent confidence interval, 0.20 to 0.78) and 0.90 in the control group (95 percent confidence interval, 0.31 to 1.49), representing a nonsignificant reduction of 45.6 percent (95 percent confidence interval for mean difference, -78.6 percent to 54.5 percent) in the FE(NO) group. There were no significant differences in other markers of asthma control, use of oral prednisone, pulmonary function, or levels of airway inflammation (sputum eosinophils). CONCLUSIONS With the use of FE(NO) measurements, maintenance doses of inhaled corticosteroids may be significantly reduced without compromising asthma control.
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Affiliation(s)
- Andrew D Smith
- Respiratory Research Unit, Department of Medicine, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
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190
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Smith AD, Cowan JO, Brassett KP, Filsell S, McLachlan C, Monti-Sheehan G, Peter Herbison G, Robin Taylor D. Exhaled nitric oxide: a predictor of steroid response. Am J Respir Crit Care Med 2005; 172:453-9. [PMID: 15901605 DOI: 10.1164/rccm.200411-1498oc] [Citation(s) in RCA: 233] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE The initial management of patients who present with persistent respiratory symptoms includes recognizing those with the potential to benefit from inhaled steroid therapy. To date, this has required undertaking a "trial of steroid" to identify responders. There is increasing evidence that steroid response is more likely in patients with eosinophilic airway inflammation, and this can be assessed indirectly using exhaled nitric oxide (FENO) measurements. OBJECTIVES We aimed to assess the predictive accuracy of FENO to identify steroid response in 52 patients presenting with undiagnosed respiratory symptoms in a single-blind, fixed-sequence, placebo-controlled trial of inhaled fluticasone for 4 weeks. METHODS Comparisons of predictive accuracy were made between FENO and other conventional predictors: peak flows, spirometry, bronchodilator response, and airway hyperresponsiveness measured at baseline. "Steroid response" was defined as change in symptoms, peak flows, spirometry, or airway hyperresponsiveness to adenosine based on established guidelines and recommendations. RESULTS Steroid response was significantly greater in the highest FENO tertile (> 47 ppb) for each endpoint. This outcome was independent of the diagnostic label. The predictive values for FENO were significantly greater than for almost all other baseline predictors, with an optimum cut point of 47 ppb. CONCLUSIONS FENO measurements greater than 47 ppb provide a means of predicting steroid response in patients with undiagnosed respiratory symptoms. Assessing airway inflammation is of more practical value than diagnostic labeling when considering the potential usefulness of inhaled antiinflammatory therapy.
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Affiliation(s)
- Andrew D Smith
- Otago Respiratory Research Unit, Dunedin School of Medicine, University of Otago Medical School, Dunedin, New Zealand
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191
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ATS/ERS Recommendations for Standardized Procedures for the Online and Offline Measurement of Exhaled Lower Respiratory Nitric Oxide and Nasal Nitric Oxide, 2005. Am J Respir Crit Care Med 2005; 171:912-30. [PMID: 15817806 DOI: 10.1164/rccm.200406-710st] [Citation(s) in RCA: 2494] [Impact Index Per Article: 131.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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192
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193
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Yildirim Z, Turkoz Y, Kotuk M, Armutcu F, Gurel A, Iraz M, Ozen S, Aydogdu I, Akyol O. Effects of aminoguanidine and antioxidant erdosteine on bleomycin-induced lung fibrosis in rats. Nitric Oxide 2005; 11:156-65. [PMID: 15491848 DOI: 10.1016/j.niox.2004.07.011] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2004] [Revised: 05/04/2004] [Indexed: 12/22/2022]
Abstract
Reactive oxygen and nitrogen species have been implicated in the pathogenesis of bleomycin-induced lung fibrosis. The effects of aminoguanidine and erdosteine on the bleomycin-induced lung fibrosis were evaluated in rats. The animals were placed into five groups: Vehicle + vehicle, vehicle + bleomycin (2.5 U/kg), bleomycin + aminoguanidine (200 mg/kg), bleomycin + erdosteine (10 mg/kg), and bleomycin + erdosteine + aminoguanidine. Bleomycin administration resulted in prominent lung fibrosis as measured by lung hydroxyproline content and lung histology, which is completely prevented by erdosteine and aminoguanidine. A strong staining for nitro tyrosine antibody in lung tissue and increased levels of lung NO were found in bleomycin group, that were significantly reduced by aminoguanidine and erdosteine. Aminoguanidine and erdosteine significantly prevented depletion of superoxide dismutase and glutathione peroxidase and elevated myeloperoxidase activities, malondialdehyde level in lung tissue produced by bleomycin. Data presented here indicate that aminoguanidine and erdosteine prevented bleomycin-induced lung fibrosis and that nitric oxide mediated tyrosine nitration of proteins plays a significant role in the pathogenesis of bleomycin-induced lung fibrosis. Also our data suggest that antifibrotic affect of antioxidants may be due to their inhibitory effect on nitric oxide generation in this model.
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Affiliation(s)
- Zeki Yildirim
- Medical Faculty, Department of Pulmonary Medicine, Inonu University, 44069 Malatya, Turkey.
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194
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Lex C, Payne DNR, Zacharasiewicz A, Li AM, Wilson NM, Hansel TT, Bush A. Sputum induction in children with difficult asthma: safety, feasibility, and inflammatory cell pattern. Pediatr Pulmonol 2005; 39:318-24. [PMID: 15678506 DOI: 10.1002/ppul.20159] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Difficult childhood asthma is defined by persistent symptoms despite maximal conventional therapy. We aimed to establish a safe method of sputum induction for these children and to study cytology and the relationship to exhaled nitric oxide (eNO). Sputum induction was performed in 38/40 children (aged 6-16 years) with difficult asthma, using 3.5% saline for four 5-min periods after bronchodilator pretreatment. Two children were excluded from sputum induction because postbronchodilator forced expired volume in 1 sec (FEV(1)) was <65% predicted. Seven of 38 children had symptoms (dyspnea and wheezing) during induction; of these, 3 experienced a fall in FEV(1) of >20% from postbronchodilator FEV(1), readily reversed with salbutamol. Sputum induction was successful in 28/38 children, with a higher success rate in children >/= 12 years than in younger children (87% vs. 50%, P = 0.02). Only 9/28 had abnormal sputum cytology; of these, 6 had predominant sputum eosinophilia (>2.5% eosinophils, </=54% neutrophils), while 3 had sputum neutrophilia (</=2.5% eosinophils, >54% neutrophils). Of 23 children with elevated eNO values, only 6 had sputum eosinophilia. In conclusion, sputum induction can be used to assess airway inflammation in children with difficult asthma, but abnormal sputum cytology is only present in a minority. Raised nitric oxide is only poorly predictive of sputum eosinophilia in these children.
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Affiliation(s)
- Christiane Lex
- Department of Respiratory Paediatrics, Royal Brompton Hospital, London, UK
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195
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Pijnenburg MW, Hofhuis W, Hop WC, De Jongste JC. Exhaled nitric oxide predicts asthma relapse in children with clinical asthma remission. Thorax 2005; 60:215-8. [PMID: 15741438 PMCID: PMC1747332 DOI: 10.1136/thx.2004.023374] [Citation(s) in RCA: 196] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Nitric oxide in exhaled air (FE(NO)) is a marker of eosinophilic airway inflammation. A study was undertaken to determine whether FE(NO) predicts asthma relapse in asymptomatic asthmatic children in whom inhaled corticosteroids are discontinued. METHODS Forty children (21 boys) of mean age 12.2 years on a median dose of 400 mug budesonide or equivalent (range 100-400) were included. FE(NO) was measured before and 2, 4, 12, and 24 weeks after withdrawal of steroids. A relapse was defined as more than one exacerbation per month, or need for beta agonist treatment on 4 days per week for at least 2 weeks, or diurnal peak flow variability of >20%. FE(NO) measurements were performed online with an expiratory flow of 50 ml/s. RESULTS Nine patients relapsed. Two and 4 weeks after withdrawal of steroids geometric mean FE(NO) in children who were about to relapse was higher than in those who did not relapse: 35.3 ppb v 15.7 ppb at 2 weeks (ratio 2.3; 95% CI 1.2 to 4.1; p = 0.01) and 40.8 ppb v 15.9 ppb at 4 weeks (ratio 2.6; 95% CI 1.3 to 5.1). An FE(NO) value of 49 ppb at 4 weeks after discontinuation of steroids had the best combination of sensitivity (71%) and specificity (93%) for asthma relapse. CONCLUSION FE(NO) 2 and 4 weeks after discontinuation of steroids in asymptomatic asthmatic children may be an objective predictor of asthma relapse.
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Affiliation(s)
- M W Pijnenburg
- Department of Paediatrics/Paediatric Respiratory Medicine, Erasmus Medical Centre/Sophia Children's Hospital, P O Box 2060, 3000 CB Rotterdam, The Netherlands
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196
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Kharitonov SA, Walker L, Barnes PJ. Repeatability of standardised nasal nitric oxide measurements in healthy and asthmatic adults and children. Respir Med 2005; 99:1105-14. [PMID: 16085212 DOI: 10.1016/j.rmed.2005.02.019] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2004] [Indexed: 11/16/2022]
Abstract
UNLABELLED Several nasal nitric oxide (NO) measurement techniques have been described, but there is not a widespread measurement technique for measurement of nasal NO. In this study we evaluated the repeatability of one technique of nasal NO measurements using the nasal application of the NIOX system. METHODS Three nasal NO measurements (NIOX Nitric Oxide Monitoring System, Aerocrine, Sweden) were made on a single occasion in 22 healthy subjects and 27 patients with asthma, aged 5-69 years. Nasal NO was sampled during breath hold from one nostril at a flow rate of 5 ml/s. RESULTS The repeatability of nasal NO assessed by the coefficient of variation (CV) was 12.5% (95% Confidence interval (CI) 11.0-14.7%) for the total population. Healthy adults had a significantly better repeatability than healthy children (P<0.008). The mean NO level for the total population was 837 ppb. The mean NO levels in children were lower than in the adults (751 and 897 ppb, respectively). The mean breath hold length needed to obtain a steady NO plateau for all subject categories combined was 20.4+/-6.01 s. The average number of attempts needed to obtain three approved NO measurements was 5.4 (range 3-13) for the total population. There were no significant differences between the different subject categories. When using two measurements per session instead of three, the overall CV was 10.5% (95% CI 8.8-13.1%). Most subjects found the measurements easy to perform and all of them would accept to do the examination as a routine. CONCLUSIONS Nasal NO measurements in NIOX may provide a useful reliable clinical tool to assess and monitor upper airways in different diseases, for example PCD and rhinitis, and are acceptable by both healthy and asthmatic adults and children, as a part of their routine visit to a physician.
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Affiliation(s)
- Sergei A Kharitonov
- Section of Airway Diseases, National Heart and Lung Institute, Imperial College, Dovehouse Street, London SW3 6LY, United Kingdom.
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197
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Chiron R, Vachier I, Godard P, Chanez P. [The measurement of exhaled nitric oxide, a new tool in the management of asthma?]. Presse Med 2005; 33:1451-8. [PMID: 15611680 DOI: 10.1016/s0755-4982(04)98953-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
A GOOD DIAGNOSTIC TEST FOR ASTHMA: Chronic airway inflammation, main feature of asthma, can be assessed by measuring the exhaled nitric oxide (NO) level. Measurement of NO is standardized, non-invasive and easy to use in both children and adults. Studies have shown that it is a good diagnostic test for asthma when NO is high. However, other conditions or pathologies must be searched for because they may influence the results. ITS PLACE IN TREATMENT: Although exhaled NO helps to characterise the patients with asthma, other studies are required to show that it can help to improve the follow-up of such patients. Nevertheless, this tool has not yet been validated in the daily treatment of asthma and further research is still ongoing.
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Affiliation(s)
- Raphaël Chiron
- Service des maladies respiratoires, Hôpital Arnaud de Villeneuve, 371 Avenue du Doyen Gaston Giraud, 34295 Montpellier Cedex 05, France.
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198
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Malmberg LP. Exhaled nitric oxide in childhood asthma--time to use inflammometry rather than spirometry? J Asthma 2004; 41:511-20. [PMID: 15360058 DOI: 10.1081/jas-120037652] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- L Pekka Malmberg
- Department of Allergology, Helsinki University Central Hospital, Helsinki, Finland.
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199
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Gelb AF, Taylor CF, Nussbaum E, Gutierrez C, Schein A, Shinar CM, Schein MJ, Epstein JD, Zamel N. Alveolar and airway sites of nitric oxide inflammation in treated asthma. Am J Respir Crit Care Med 2004; 170:737-41. [PMID: 15229098 DOI: 10.1164/rccm.200403-408oc] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The goal of this study was to identify airway and alveolar site(s) of inflammation using exhaled nitric oxide (NO) as a marker in treated patients with asthma, including response to oral corticosteroids, and correlate these sites with expiratory airflow limitation. In 53 (24 male) patients with asthma, age 43 +/- 23 years (mean +/- SD) and all on inhaled corticosteroids, post 180 microg aerosolized albuterol, FEV(1) was 74 +/- 23% predicted and FEV(1)/FVC was 68 +/- 11%. Exhaled NO at 100 ml/second was 27 +/- 23 ppb (p < 0.001 compared with normal, 12 +/- 15 ppb). Bronchial NO maximal flux was 2.4 +/- 3.1 nl/second (p < 0.001 compared with normal, 0.85 +/- 0.55). Alveolar NO concentration was 7.0 +/- 7.4 ppb (p = 0.01 compared with the normal value, 3.2 +/- 2.0 ppb). There was no significant correlation between FEV(1) % predicted or lung elastic recoil and NO bronchial flux or alveolar concentration. However, there was a weak but significant correlation between NO bronchial flux and alveolar concentration (Spearman r = 0.50, p < 0.001). In 10 subjects with asthma on inhaled corticosteroids, 5 days of 30 mg prednisone resulted in isolated significant decreases in NO alveolar concentration, from 13 +/- 10 to 4 +/- 4 ppb (p = 0.002). Despite treatment, including inhaled corticosteroids, patients with asthma may have ongoing separate airway and alveolar sites of NO inflammation, the latter responsive to oral corticosteroids.
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Affiliation(s)
- Arthur F Gelb
- Department of Pharmacy Services, Lakewood Regional Medical Center, Lakewood, California, USA.
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200
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Abstract
PURPOSE Asthma is now defined as a TH2-mediated inflammatory disease involving both large and small airways. However, assessment of airways inflammation is limited by techniques that are time consuming and possibly distressing to the patient. Exhaled nitric oxide, an easily and rapidly obtained noninvasive study, is a potential surrogate for measuring airways inflammation, but its clinical utility remains to be determined. This review examines the role of exhaled nitric oxide in assessing and directing therapy of asthmatic airways inflammation. RECENT FINDINGS It is well established that exhaled nitric oxide is increased in patients with untreated asthma and decreases with corticosteroid treatment. Exhaled nitric oxide also generally correlates with eosinophilic inflammation in asthmatic patients. Recent studies show that this correlation is especially pronounced in atopic subjects with asthma when compared with nonatopic subgroups. Recent studies also show that exhaled nitric oxide may be useful in identifying subclinical inflammation, assessing the antiinflammatory effects of asthma medications other than inhaled or oral corticosteroids, and heralding an asthma exacerbation. A number of new studies assert the utility of exhaled nitric oxide as a diagnostic tool for asthma. SUMMARY Exhaled nitric oxide may be a useful parameter for monitoring asthmatic inflammation, adjusting therapy, and diagnosing asthma, although prospective longitudinal trials investigating the correlation between exhaled nitric oxide and clinical outcomes are necessary to determine its utility.
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Affiliation(s)
- Michelle R Zeidler
- David Geffen School of Medicine at University of California, Los Angeles, USA.
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