RESUMEN

BACKGROUND: Significant risk factors for persistence of asthma later in life are family history of allergies, early allergic sensitization and bronchial hyperresponsiveness (BHR). The evolution of BHR in young children without allergic sensitization and with house dust mite allergy (HDM) was investigated. METHODS: In this retrospective analysis, electronic charts of 4850 young children with asthma and wheezy bronchitis between 2005 and 2018 were reviewed in order to study all patients ≤6 years with BHR assessed by methacholine provocation tests (MCT) at least once (n = 1175). Patients with more than two follow-up measurements were divided in group 1 (no allergic sensitization; n = 110) and group 2 (HDM allergy; n = 88). Additionally, skin prick test, exhaled nitrite oxide (eNO), and asthma treatment were analyzed. RESULTS: Forty-seven patients of group 1 aged median 4.3 years and 48 patients of group 2 aged median 4.7 years showed initially severe BHR <0.1 mg. At follow-up, patients with HDM were more likely to show persistence of severe BHR than non-sensitized patients (severe BHR group 1: n = 5 (10.6%) vs. group 2: n = 21 (43.8%), p < .001). In addition, 89.4% of group 1 had mild to moderate or no BHR, compared to only 56.2% of group 2. There was a significant difference in eN0 (median group 1: 9 ppb vs. group 2: 26 ppb, p < .001), at last follow-up. Age, sex, and asthma therapy had no effect on BHR. CONCLUSION: In young children without sensitization BHR normalizes, whereas HDM allergy indicates a persistence of asthma beyond infancy.

Asunto(s)

RESUMEN

BACKGROUND: Mild asthma is often characterized by normal spirometric values and a negative bronchodilation test (BDT), which makes accurate diagnosis challenging. The aim of our study was to evaluate the diagnostic accuracy of fractional exhaled nitric oxide (FeNO) in mild asthma. METHODS: In adults with symptoms suggestive of asthma and normal spirometry values, BDT, FeNO, BPT and skin prick testing were performed. Patients with positive BPT started inhaled corticosteroid (ICS) therapy. Those with positive response to ICS were considered asthmatics. RESULTS: There were 142 asthmatics and 140 non-asthmatics. No significant difference was found in BDT between the groups, p = 0.233. Median FeNO levels were significantly higher in the asthma group (49.5 ppb) than in the non-asthma group (23 ppb), p < 0.001. BPT was positive in 145 (51.42%) and negative in 137 (48.58%) patients. Positive response to ICS treatment was recorded in 142/145 (97.9%) patients. In diagnosing asthma, FeNO ≥ 25 ppb had a sensitivity of 75.4% and specificity of 47.9%. CONCLUSIONS: FeNO has insufficient sensitivity and specificity in mild asthma and the application of BPT is often necessary to establish an accurate diagnosis.

RESUMEN

OBJECTIVE: Airway hyperresponsiveness (AHR) is a hallmark of asthma. Methacholine challenge test which is mostly used to confirm AHR is not routinely available. The aim of this study was to investigate the predictive values of fractional exhaled nitric oxide (FeNO), impulse oscillometry (IOS), and plethysmography for the assessment of AHR in children with well-controlled asthma. METHODS: 60 children with controlled allergic asthma aged 6-18 years participated in the study. FeNO measurement, spirometry, IOS, and plethysmography were performed. Methacholine challenge test was done to assess AHR. PC20 and dose response slope (DRS) of methacholine was calculated. RESULTS: Mild to severe AHR with PC20 < 4 mg/ml was confirmed in 31 (51.7%) patients. Baseline FeNO and total specific airway resistance (SRtot)%pred and residual volume (RV)%pred levels in plethysmography were significantly higher and FEV1%pred, FEV1/FVC%pred, MMEF%pred values were lower in the group with PC20 < 4 mg/ml. FeNO, SRtot%pred, and RV%pred levels were found to be positively correlated with DRS methacholine. The higher baseline FeNO, frequency dependence of resistance (R5-R20) in IOS and SRtot%pred in plethysmography were found to be significantly related to DRS methacholine in linear regression analysis (ß: 1.35, p = 0.046, ß: 4.58, p = 0.002, and ß: 0.78, p = 0.035, respectively). The cut-off points for FeNO and SRtot% for differentiating asthmatic children with PC20 < 4 mg/ml from those with PC20 ≥ 4 mg/ml were 28 ppb (sensitivity: 67.7%, specificity: 72.4%, p < 0.001) and 294.9% (sensitivity: 35.5%, specificity: 96.6%, p = 0.013), respectively. CONCLUSION: IOS and plethysmography may serve as reliable and practical tools for prediction of mild to severe methacholine induced AHR in otherwise "seemingly well-controlled'' asthma.

Asunto(s)

RESUMEN

BACKGROUND: Asthma in athlete populations such as Olympic athletes has various pathogeneses. However, few reports are available on the features of asthma in the athlete population in clinical practice. In this study, we focused on classifying asthma in Japanese athlete population. METHODS: We performed a cluster analysis of data from pulmonary function tests and clinical biomarkers before administering inhaled corticosteroids (ICS) therapy in athlete population of individuals diagnosed with asthma (n = 104; male, 76.9%; median age, 16.0 years), based on respiratory symptoms and positive data on methacholine provocation tests. We also compared backgrounds, sports types, and treatments between clusters. RESULTS: Three clusters were identified. Cluster 1 (32%) comprised athletes with a less atopic phenotype and normal pulmonary function. Cluster 2 (44%) comprised athletes with a less atopic phenotype and lower percent predicted forced expiratory volume in 1 s (%FEV1) values, despite less symptomatic state. Cluster 3 (24%) comprised athletes with a strong atopic phenotype such as high eosinophil count in the blood and total serum immunoglobulin E level. After treatment with ICS or ICS plus long-acting ß-adrenergic receptor agonist for 6-12 months, %FEV1 values were significantly improved in Cluster 2 athletes, whereas Cluster 3 athletes had a significant decrease in the fraction of exhaled nitric oxide compared to pretreatment values. CONCLUSIONS: These data suggest three clusters exist in Japanese athlete population with asthma. Between the clusters, the characteristics differed with regard to symptoms, atopic features, and lower %FEV1 values. The pathogeneses between clusters may vary depending on the inflammation type and airway hyperresponsiveness.

Asunto(s)

RESUMEN

Objective To evaluate the diagnostic value of astograph methacholine provocation test for bronchial asthma.Methods A total of 238 asthma patients and 499 non-asthma patients participated in the detection by astograph methacholine provocation test.Statistical methods were used to analyze the differences of astograph parameters and find the indicators of asthma diagnosis and the critical value.Results Dmin,Cmin and PD15 were much lower in the asthma group (P ＜ 0.01),compared with the the non-asthma group,when SGrs,SGrs/Grs cont were much higher (P ＜ 0.01).SGrs was relevant with Dmin,Cmin,PD15 in the asthma group (P =0.000;r =0.685,r =0.657,r =0.639) as well as the SGrs/Grs cont did (P =0.000,r =0.775;r =0.740,r =0.708).In ROC analysis,Dmin presented an AUC of 0.661,the cutoff value was 2.71 unit,with a sensitivity of 0.739 and specificity of 0.551.PD15 presented an AUC of 0.746,the cutoff value was 4.856 5 unit,with a sensitivity of 0.693 and specificity of 0.684.Conclusion Astograph methacholine provocation test shows good sensitivity and specificity in the diagnosis of asthma,particularly when Dmin ≤ 2.71 Unit or PD15 ≤ 4.8565 Unit as the cutoff value.

RESUMEN

OBJECTIVE: Control of airway inflammation is the cornerstone of asthma management. The aim of the present pilot study was to assess the effects of a leukotriene receptor antagonist (LTRA) added to a basic treatment of inhaled corticosteroids (ICS) and long-acting beta-agonist (LABA) on airway hyperresponsiveness, inflammation, and quality of life in well-controlled patients with asthma. RESEARCH DESIGN AND METHODS: Seventeen patients (age 18-65, 11 women) with well-controlled asthma presenting airway hyperresponsiveness to mannitol and methacholine challenge were given add-on montelukast on a stable ICS + LABA for 4 weeks. Quality of life and selected parameters of airway inflammation were measured at baseline and at study end. (ClinicalTrials.gov (NCT01725360)). RESULTS: Adding montelukast to ICS + LABA resulted in an increase in mean FEV1 (+4.5%, p = 0.057), cumulated higher dose of mannitol (+32.5%, p = 0.023) and methacholine (+17.2%, 0.237) in the provocation test, lower airway reactivity with mannitol and methacholine (response dose ratio (RDR) -50.0%, p = 0.024 and -44.3%, p = 0.006, respectively), and improved airway sensitivity to mannitol and methacholine (+12.1%, p = 0.590 and +48.0%, p = 0.129 for PD15 and PD20 FEV1, respectively). Changes in inflammation parameters (blood eosinophil count, serum eosinophil cationic protein, and exhaled nitric oxide) were consistent with these findings. Asthma-related quality of life improved significantly in all domains and overall (from 5.3 at baseline to 6.1 at the final visit, p < 0.001). The main limitation was the absence of a control group. CONCLUSION: The consistency of the changes in airway hyperresponsiveness and inflammation as well as in quality of life observed with an add-on therapy with montelukast in well-controlled asthma patients during 4 weeks suggests that residual inflammation may represent an area for further improvement of asthma control to be explored in adequately powered randomized controlled trials.

RESUMEN

BACKGROUND: Deep inspiration not only has a bronchodilatory effect but also a bronchopro- tective effect. We compared the 2-min tidal breathing method and the five-breath dosimeter method to evaluate effect of deep inspiration on airway narrowing during methacholine provocation tests (MPT) in normal subjects. METHODS: Eleven normal volunteers (seven males and four females) inhaled five doses of methacholine (25mg/ml) at 5-min intervals during the 2-min tidal breathing method and the five-breath dosimeter method. MPT was cross-overly performed by the two methods. On first visit, a questionnaire for symptoms, allergy skin test, spirometry, and MPT (2-min tidal breathing and five-breath dosimeter method) were performed. On second visit, pulmonary function tests and methacholine challenge using the 25mg/mL dose were performed on two separate days at the same time each day. The perception of dyspnea during methacholine challenge was scored using modified Borg scale. The recovery time from maximal decrease in FEV1 to baseline FEV1 was checked without using bronchodilator after MPT. RESULTS: The maximal decreases in FEV1 and FVC during the 2-min tidal breathing method were 38.8+/-5.3% and 27.8+/-5.1%, respectively. The maximal decreases in FEV1 and FVC during the five-breath dosimeter method were 16.5+/-6.1% and 14.2+/-4.9%, respectively. Score on Borg scale during the 2-min tidal breathing method at methacholine dose 1 was from 0.5 to 7. The FEV1 and FVC at methacholine dose 1, 2, 3, 4, 5 showed significantly greater decreases during the 2-min tidal breathing method compared to those during the five-breath dosimeter method. There was significant correlation between maximal decrease in FEV1 during the five-breath dosimeter method and recovery time from decrease in FEV1 to baseline FEV1 (r=0.82; p<0.01). A significant correlation (r=0.79; p<0.05) was found between decrease in FEV1 at methacholine dose 1 during the 2-min tidal breathing method and perception score. CONCLUSION: These observations indicate that the continuous generation method produces more bronchoconstriction than the dosimeter method for delivering methacholine aerosol during MPT, suggesting inhibition of deep inspiration enhances methacholine induced airway narro- wing in normal subjects.

Asunto(s)

RESUMEN

PURPOSE: Intermittent bronchial obstruction and increased airway responsiveness to inhaled nonspecific stimuli are main features of asthma. We retrospectively studied a group of children with asthma to investigate the contribution of childhood asthma characteristics and degree of bronchial responsiveness in combination with other variables in the prediction of adult level of pulmonary function & bronchial responsiveness. METHODS: We carried out the retrospective study on 65 adult patients who had been performed methacholine provocation test at Yonsei university children's allergic clinic from March 1994 to July 1997. These cases were diagnosed bronchial asthma on childhood. RESULTS: 1) In this study 65 patients were investigated, 45 subjects(69.3%)(A) were negative on methacholine provocation test, & 20 subjects(30.7%)(B) were positive. 2) Age of onset of asthma, A group was earlier than B group.(1.2 vs. 3.8 year) 3) There was significant relationship between mean PC20-methacholine and % predicted FEV. 4) There was no significant difference between A & B group in the number of allergen & duration included in the immunotherapy. CONCLUSIONS: We conclude that age of onset, degree of symptoms, % predicted FEV of childhood asthma are relevant to predict the outcome of the adult pulmonary function level, and the childhood degree of bronchial responsiveness are important for the prediction of adult degree of bronchial responsiveness among children with asthma.

Asunto(s)

RESUMEN

BACKGROUND: Bronchial asthma is characterized by noctunal dyspnea, cough and wheezing because of airway hyperresponsiveness to nonspecific stimuli. These symptoms and signs are also observed in patients with congestive heart failure. Therefore, this is so called "cardiac asthma". There are lots of experimental and clinical datas to suggest that airway dysfunctions occur in acute and chronic congestive heart failure. However, it is still controversial whether bronchial hyperresponsiveness is present in patients with congestive heart failure. To assess whether bronchial hyperresponsiveness is present in patients with congestive heart failure and to demonstrate the relationship between bronchial responsiveness and vascular pressure, we performed methacholine provocation test in 11 patients with mitral valvular heart disease. METHODS: All patients were in the New York Heart Association functional class II and treated continuously with digoxin and/or dichlozid and/or angiotensin converting enzyme inhibitor except one patient. All patients were undergone right and left side heart catheterization for hemodynamic measurements. A 20 percent fall of peak expiratory flow rate were considered as positive response to methacholine provocation test. RESULTS: 1) Only one patient who has normal pulmonary artery pressure, pulmonary capillary wedge pressure, cardiac index was positive in methacholine provocation test. 2) Their mean pulmonary artery pressure, pulmonary capillary wedge pressure were 21.72 +/- 9.70mmHg, 15.45 +/-8.69mmHg respectively which were significantly higher. CONCLUSION: It is speculated that in stable congestive heart failure patients, bronchial responsiveness as assessed by methacholine provocation test may not be increased.

Asunto(s)

RESUMEN

PURPOSE: Bronchial asthma is a disorder that is characteized by symptoms of reversible airway obstruction and increased responsiveness of the bronchus and to quantify the degree of br onchial hyperresponsivenes can be very helpful in determing the severity of disease and the prognosis. But the Methacholine provocation test is not always easy to be performed in all patients. Thus we designed this trial to know the relationship between the degree of bronchial hype rresponsiveness by Methacholine and the severity of asthma symptoms, pulmonary function te st and atopic findings. METHODS: Methacholine provocation test was performed on 60 clinically stable asthma patients who visited the pediatric allergy clinic of Taegu Fatima Hospital from July, 1992 to June, 1 993. All patients were free of URI for at least 6 weeks and medications were withhold for 2 weeks for corticosteroid or beta receptor agonist and at least 2 days for theophylline. All subjects ha d FEV1 more than 70% of predicted value, and more than 20% of reversible obstruction. Disease severity score(DSS) was compared by the number of asthmatic attacts, clinical picture, therapeutic medications and the Airway reactivity score(ARS) was measured on the number of nonspecipic irritants provoking the bronchial hyperresponsivess. Methacholine provocation test was performed as follows; Normal saline was inhaled 5 times by tidal breath through De Vilbiss 646 inhaler and FEV1 was measured as baseline. According to Chai standardized method, Mathacholine was diluted to 0.075-25mg/ml concentration and inhaled 5 times and accumulated Methacholine was graded 0.375-225.0 Breath Units(One BU = 1 inhalation of 1 mg/ml). PD20 was determined to the concentration at which the FEV1 faIled to 20% below the baseline. RESULTS: 1) PD20 were distributed variably between 0.375 BU and 225.0 BU 2) Bronchial hyperresponsiveness was high on asthma with allergic rhinitis(p<0.05). 3) Bronchial hyperresponsiveness by Methacholine provocation test had significant correlation both DSS(r= -0.473; p<0.01) and ARS(r= -0.32; p<0.05). 4) Bronchial hyperresponsiveness by Methacholine provocation test had significant correlation to baseline FEV1/FVC ratio(r= -0.63; p<0.01). 5) Bronchial hyperresponsiveness by Methacholine provocation test had no statistical significant correlation to serum IgE value(r= -0.24; p<0.05). CONCLUSIONS: The severity of bronchial hyperresponsiveness by Methacholine provocation t est had significant correlation with DSS and ARS, and there was a close relation BHR to the baseline FEV1/FVC1 ratio too. Thus exact history about clinical pictures, medications, provocating irritants in asthmatic patients and baseline FEV1/FVC ratio can be very helpful in assessing the bronchial hyperresponsiveness.

Asunto(s)