Role of astograph methacholine provocation test in diagnosis of bronchial asthma / 实用医学杂志

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.

The effect of deep inspiration on methacholine induced bronchoconstriction / 천식및알레르기

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.

A Clincal Follow-up Study of Asthma from Childhood to Adulthood / 소아알레르기및호흡기학회지

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.

Relationship between Bronchial Hyperresponsiveness by Methacholine Provocation and the Severity of Asthma Symptoms, Pulmonary Function and Atopy

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.

Bronchial Responsiveness in Patients with Mitral Valvular Heart Disease / 결핵

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.