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At least 19 recordsLinked to original sources
PubMed1987

A new glass microfibre-based histamine analysis for allergy testing in children. Results compared with conventional leukocyte histamine release assay, skin prick test, bronchial provocation test and RAST.

A new microfibre method for allergy testing measuring histamine release from human basophil leukocytes is described. Samples of 50 microliter washed blood are challenged with the suspected allergens. Released histamine is bound to microfibres and measured by a spectrofluorometrical method after removal of interfering substances by washing. The microfibre method (HR-MM) was compared to the conventional histamine release assay using the Ficoll-Hypaque gradient method (HR-FH) in 19 allergic children tested with one of three allergens. In addition, a comparison was made between the microfibre method and in vivo provocation tests, i.e. skin prick test (SPT), bronchial provocation test (BPT) and allergen specific serum IgE (RAST). It was found that the same individuals responded with histamine release to the same allergens in both histamine release assays, and the dose-response curves were almost identical. A positive correlation was found between the in vivo and in vitro tests. Thus it is concluded that the new method can provide reproducible, analytically precise (at the nanogram level) histamine release results in pediatric cases where: a positive SPT does not correlate with case history; BPT may be considered too hazardous or inconvenient; confirmation of negative or inconclusive SPT or RAST is needed. In contrast to other histamine release assays it is a convenient diagnostic tool in children since only small amounts of blood are needed and at least 96 tests can be carried out in 2 1/2 h.

Asthma↗
PubMed1975

The correlation between skin tests, bronchial provocation tests and the serum level of IgE specific for common allergens in patients with asthma.

Cutaneous and bronchial immediate allergic reactivity and the serum level of IgE specific for each of four common inhalant allergens were determined for 153 asthmatic patients. Positive bronchial reactivity to an extract was not detected in any of the patients with a negative prick test reaction to that extract but did occur in 9% of the patients in whom the serum tests results for IgE specific to that allergen fell within the range regarded as negative. Highly significant correlation coefficients between the degree of bronchial and cutaneous allergic reactivity to the allergen extracts were found and these were slightly but significantly less than the correlation between the serum level of allergen specific IgE and the degree of bronchial allergic reactivity to the allergen extracts. These findings indicate that the results both of prick testing with appropriate extracts and estimation of the serum level of allergen specific IgE can be used to predict not only the presence of detectable bronchial reactivity to inhalant allergens but also the degree of this reactivity. However, for the routine investigation of asthmatic patients measurement of the serum level of allergen specific. IgE would appear to have little advantage over properly performed prick tests.

Aerosols↗
PubMed1993

[Bronchial provocation test in bronchial asthma].

Methacholine provocation test, bronchial reversibility test, aspirin inhalation test, and cough provocation test have been performed at our institute to examine pathophysiology and to diagnose bronchial diseases. Bronchial responsiveness to methacholine correlated to baseline pulmonary functions, especially to % predicted value of forced expiratory volume in 1 second (%FEV1) in asthma and sinobronchial syndrome. Bronchial reversibility was greater with beta 2-agonists than with muscarinic antagonists in asthma while it was less with beta 2-agonists than with muscarinic antagonists in sinobronchial syndrome. Our protocol for aspirin inhalation test consists of a screening test and threshold measurement test and is useful for diagnosis of analgesics-induced asthma. Capsaicin provocation test to measure airway cough receptor sensitivity is used to diagnose chronic cough.

Aspirin↗
PubMedDate not supplied

Decrease of beta-receptors after the antigen-specific bronchial provocation test in bronchial asthma.

Airway hyperreactivity to different stimuli is a characteristic feature of bronchial asthma. The beta-adrenergic theory, as proposed by Szentivanyi in 1968, tried to explain with beta-adrenergic dysfunction, the cause not only of bronchial hyperreactivity but of all atopic diseases. In a previous work, we found that asymptomatic asthmatic patients presented a number of beta-receptors similar to that of a normal control group, while symptomatic asthmatic patients presented a significantly decreased number when compared to both groups (40% decrease). In view of these results, we proposed to study the possible changes in the number of beta-receptors in asymptomatic asthmatic patients after a bronchial provocation test. Fifteen patients, diagnosed of bronchial asthma and sensitive to the house dust mite, D. pteronyssinus, were studied. All were free of medication and asymptomatic at least 90 days before the study. A test of specific bronchial provocation was performed on 10 patients, determining the number of beta-receptors in basal conditions, after 30 minutes and 24 hours. The other five patients underwent an unspecific provocation test with methacholine, with determination of the beta-receptor number at basal conditions, and 24 hours later. Only a significant decrease (30.4%) was found in the beta-receptor numbers, 24 hours after specific bronchial provocation with p less than 0.025 with the Student test for paired data. With regards the beta-adrenergic theory of atopy, in our opinion our results show that the detected decrease of beta-receptors would be the consequence and not the cause of atopic diseases.

Allergens↗
PubMed2005

Exhaled nitric oxide in the diagnosis of asthma: comparison with bronchial provocation tests.

BACKGROUND: Bronchial provocation tests such as exercise, methacholine (MCH), and adenosine-5'-monophosphate (AMP) challenges are used extensively in the diagnosis of asthma. A study was undertaken to determine whether exhaled nitric oxide (eNO) can be used to diagnose asthma in patients with non-specific respiratory symptoms and to compare this test with conventional provocation tests. METHODS: Patients with non-specific respiratory symptoms and normal spirometric parameters were included in the study. eNO was measured and exercise, MCH and AMP challenges performed in all subjects. Patients were defined as asthmatic based on clinical follow up 24 months after testing. RESULTS: Forty patients were considered asthmatic and 45 were not. The area under receiver operating characteristic curves gave values of 0.896 for eNO, 0.781 for exercise, 0.924 for MCH, and 0.939 for AMP (p = 0.033, 0.575 and 0.085 for eNO v exercise, MCH and AMP respectively). From our data, a cut off value of NO > 7 ppb at a flow rate of 250 ml/s best differentiates between asthmatics and non-asthmatics (sensitivity 82.5%, specificity 88.9%). Optimal cut off values for other tests were exercise: deltaFEV1 > or = 10% (sensitivity 57.9%, specificity 100%); PC20-MCH: < or = 3 mg/ml (sensitivity 87.5%, specificity 86.7%); and PC20-AMP: < or = 150 mg/ml (sensitivity 89.5%, specificity 95.6%). CONCLUSIONS: Measurement of eNO can be used as a safe, simple and rapid test for the diagnosis of asthma and is as good as bronchial provocation tests.

Adenosine Monophosphate↗
PubMedDate not supplied

Relationship between skin tests and bronchial provocation tests with allergens found in organic dusts in patients with bronchial asthma.

A group of 153 patients with bronchial asthma were subjected to bronchial provocation and intracutaneous tests with allergen from the gram negative bacterium Erwinia herbicola which commonly occurs in organic dusts. Of this group, 80 persons were also examined with both tests with the allergen of Aspergillus fumigatus and 96 persons with the house dust extract. The frequency of positive skin reactions to the tested allergens was much greater than that of the positive bronchial reactions. No significant correlation was found to exist between the frequency and intensity of the bronchial and skin reactions except for delayed and late reactions to Erwinia herbicola. The authors conclude that bronchial provocation tests represent a much more specific and reliable method in the assessment of the clinical status of patients with extrinsic asthma than do skin tests.

Adult↗
PubMed2005

[Indirect bronchial provocation tests: a new, specific group of bronchial provocation tests for asthma].

Asthma is characterized by a variable airway obstruction, bronchial hyperresponsiveness and airway inflammation. Usually, bronchial hyperresponsiveness is measured in the clinic by provocation with non specific stimuli such as histamine or methacholine. These stimuli are called direct, as they constrict the airways by a direct stimulation of airway smooth muscle. Pharmacological stimuli such as adenosine, tachykinins and bradykinin, and physical stimuli such as exercise, isocapnic hyperventilation or hypertonic saline, are called indirect stimuli: they stimulate inflammatory cells and/or neuronal cells and the released mediator and/or neurotransmitter causes the airways to narrow. In the past 10 years the mechanisms and receptors involved in the airway narrowing caused by these indirect bronchial challenges have been characterized. It has become clear that indirect challenges form a specific group of challenges that play a role in the diagnosis and the monitoring of asthma.

Adenosine↗
PubMed1984

A study on the reproducibility of specific bronchial provocation testing in children.

Bronchial provocation tests with housedust were carried out on thirty-five asthmatic children aged 4-13. Each patient was tested twice. Subjects were studied with two different doses of allergen: 1200 and 3600 micrograms. There was reproducibility in 80% of the seventy tests performed, allowing confirmation of the reliability of the test. Furthermore, reproducibility was better when lower doses of allergen were inhaled. The intensity of the bronchial response sometimes varied in the same subject. These variations were greater when the inhaled volume increased. Immediate and delayed reactions together and delayed reactions alone were frequent (60% of cases); this should therefore be taken into account when studying the reproducibility of specific bronchial provocation test.

Adolescent↗
PubMed1993

Allergen extracts. Standardization of preparations for bronchial provocation tests. A position paper. (EAACI Sub-committee on Bronchial Provocation Tests).

Standardization of allergen provocation tests of the airways requires standardization of each of the steps involved, including standardization of the extracts used. The value of international standards is emphasized and so is the determination of a clinically relevant potency. The allergen extracts used for bronchial provocation tests must be compared with qualitatively and quantitatively clinically relevant standards using complementary immunochemical and biological methods. Ideally the same extracts should be used for diagnosis (skin test, specific IgE determinations, provocations) and treatment (immunotherapy). The importance of the biological compared with the non-biological methods is that the biological methods are established in allergenic patients in order to select a clinically relevant potency of the allergen in question, and this potency ought to be confirmed in clinical trials. Once established the biological potency of an in-house preparation can be reproduced by supplementary in vitro methods. Very few commercial allergen preparations are available which fulfil the above-mentioned criteria.

Allergens↗
PubMedDate not supplied

[Usefulness of specific bronchial provocation tests in the diagnosis of compensable occupational allergic pneumopathies].

The A.A studied the bronchial reactivity of 309 subjects accusing a working respiratory disease. It had been valued the utility of specific provocation bronchial test for diagnosis of allergic bronchopneumopathies. The test, performed with working antigens pool, not only confirms the low percentage of allergic respiratory disease among considered workers (joiners, painters and millers) it also shows its sensibility only in subjects with a sure story of bronchial asthma. The A.A. say, that it's not really necessary to perform the test in all subjects that submit to diagnostic screening for industrial insurance reasons.

Asthma↗
PubMed1982

Clinical symptoms and results of skin test, RAST and bronchial provocation test in thirty-three papain workers: evidence for strong immunogenic potency and clinically relevant 'proteolytic effects of airborne papain'.

Seventeen out of thirty-three workers who have been exposed to airborne papain at their place of work regularly developed asthmatic symptoms such as shortness of breath, wheezing, coughing, sneezing, rhinorrhea and conjunctival irritation upon contact with this proteolytic enzyme. Investigations by RAST, skin test and bronchial provocation test proved IgE-mediated hypersensitivity to papain in fourteen symptomatic workers. Ten of these were in a screening investigation involving twenty-nine of the thirty-three workers; i.e. the incidence of IgE-mediated sensitization was 34.5% of this group. Bronchial provocation of as little as 0.001--0.5 mg of papain was shown to elicit immediate or dual asthmatic reactions in all eight tested workers with RAST values greater than 3 u/ml. On the other hand, inhalation of 0.5 mg of papain did not cause any remarkable change in non-exposed asthmatics. Occupation-related blood-stained nasal secretions and/or cutaneous flare reactions in all four heavily-exposed papain workers, of whom three had negative skin test and RAST results, suggest a direct effect of the proteolytically active enzyme on human tissue. There was a significant elevation (P less than 0.001) of serum trypsin inhibitory capacity in papain workers which seems to depend on the degree of exposure. No significant differences between symptomatic and asymptomatic workers in alpha 1-antitrypsin (Pi) phenotype subtypes were found.

Adult↗
PubMed1979

Papain-induced asthma: diagnosis by skin test, RAST and bronchial provocation test.

Seven out of eleven workers occupationally exposed to airborne papain developed immediate hypersensitive reactions, predominantly asthma and rhinitis. Skin tests and RAST with papain were positive in all symptomatic workers, but not in the four asymptomatic workers. Furthermore, out of forty non-exposed asthmatics, thirty-eight had negative RAST results and all had negative skin test results. Bronchial provocation tests with 0.15-0.5 mg papain performed in five patients with a positive case history showed in each case an immediate asthmatic reaction; in addition to that, one patient developed signs of a dual asthmatic reaction. Our results suggest that airborne papain is a highly immunogenic agent in humans, which induces type I allergic reactions in a large percentage of the exposed subjects.

Asthma↗
PubMed1994

[Clinical evaluation of whole blood histamine release test simultaneously testing multiple allergens--correlated with bronchial provocation test].

We compared the efficacy of the novel histamine release test (HRT), which allows the determination of many allergens at the same time using a small amount of whole blood, with other conventional allergen diagnostic tests. HRT and RAST were both performed along with bronchial provocation tests (BPT) on 44 bronchial asthma patients in whom the etiologic allergen could not be determined by either intracutaneous tests (ICT) or ophthalmic response tests (ORT). The HRT uses a microtiterplate on which glass fibers have 10 kinds of allergens affixed. The histamine release ability at 6 different concentrations of each kind of allergen was examined. The concordance of HRT with respect to BPT was the highest at 82% in comparison with RAST at 66%, ICT at 55% and ORT at 60%. With each of the allergens, HRT had the highest concordance with BPT. On the other hand, RAST, ICT and ORT showed different results depending on the allergens. The positive predictive value of HRT was the highest at 76% compared with RAST at 59%, ICT at 51% and ORT at 64%. From these results, we concluded that HRT is a more useful diagnostic method for the confirmation of a clinical allergy than other conventional diagnostic methods.

Adolescent↗
PubMed1991

Quantitative skin prick and bronchial provocation tests with platinum salt.

Occupational asthma due to platinum salts is a frequent disease in platinum refineries. The diagnosis is based upon a history of work related symptoms and a positive skin prick test with platinum salts. Bronchial provocation tests have not been performed in epidemiological studies because the skin test is believed to be highly specific and sensitive. As no reliable data about this issue currently exist, this study assesses the use of skin prick and bronchial provocation tests with methacholine and platinum salt in platinum refinery workers. Twenty seven of 35 workers, who were referred to our clinic with work related symptoms and nine control subjects with bronchial hyperreactivity underwent a skin prick test and bronchial provocation with methacholine and platinum salt. For skin prick and bronchial provocation tests with platinum salt a 10(-2)-10(-8) mol/l hexachloroplatinic acid solution, in 10-fold dilutions was used. Four of the 27 subjects and all controls showed neither a bronchial reaction nor a skin reaction. Twenty three subjects were considered allergic to platinum salt; 22 of these showed a fall of 50% or more in specific airway conductance after inhalation of the platinum salt solution. Four workers experienced a positive bronchial reaction despite a negative skin prick test. No correlation of responsiveness to methacholine with responsiveness to platinum salt was found, but the skin prick test correlated with the bronchial reaction to platinum salt (rs = 0.50, p less than 0.023, n = 22). One dual reaction was seen in bronchial provocation tests. Side effects of both skin tests and bronchial provocation tests with platinum salt were rare and were not encountered in workers without a skin reaction to platinum salt. It is concluded that bronchial provocation tests with platinum salts should be performed on workers with work related symptoms but negative skin tests with platinum salts.

Adult↗