PubMed HealthSearch

SEARCH · PubMed Health

Results for “Bronchial Provocation Tests”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2Linked to original sources

Specific IgE estimations by RAST in Japanese asthmatics compared with skin, passive transfer and bronchial provocation tests.

198 asthmatics and twenty healthy persons were studied by RAST and in vivo tests with four common inhalant allergens. (a) Higher RAST classes were elicited with mite (Dermatophagoides farinae) extract and lower classes with other allergens. The agreement between positive RAST and skin or P-K tests was highest with the mite extract. RAST sensitivity was dependent on the kinds of allergens and was most sensitive to mite extract. Positive RAST was most closely related to the prick test reactions. (b) RASTs to house dust and mite extract were examined in terms of the threshold dosage of house dust and also the types of bronchial response (early, dual and late) induced by a certain amount of house dust; higher RAST classes were found in subjects with bronchial response to the dual or early type, elicited by a threshold dosage of diluted extract, while lower RAST classes were found in cases of the late-type response elicited by the threshold dosage of concentrated extract. (c) Changes in IgE antibodies to house dust and mite extract were estimated in patients with positive house dust provocation. A greater increase occurred in cases of dual or early response, a smaller increase in those with a late response. Despite discordances in skin tests and RAST between house dust and mite extracts, the increases in IgE antibodies to mite extracts as well as house dust were observed in all cases, presumably caused by an allergenic identity between the allergens.

Adolescent

The effect of ICI 74,917 on asthma and bronchial provocation tests.

A study was made of the protective action of the anti-allergic drug ICI 74,917, a phenanthroline derivative, in specific allergen provocation tests and in combating clinical symptoms in thirteen asthmatic out-patients. It was found that ICI 74,917 was able to diminish allergen-induced bronchoconstriction significantly (P less than 0.01) during both the placebo period and during chronic treatment with ICI 74,917 for 4 weeks. The results obtained during these two periods did not differ significantly. There was not, however, any statistically significant difference in the symptom scores or PEF rates during the treatment with ICI 74,917 or placebo for 1 month. This may indicate that although ICI 74,197 is able to prevent bronchoconstriction in an allergen provocation test, it failed to improve asthma clinically. No signs of the phenomenon of tachyphylaxis were observed in the present study. The Student's t-test was used in the statistical analysis.

Adolescent

Relation between skin tests, inhalation tests, and histamine release from leucocytes and IgE in house-dust mite allergy.

This study was concerned with the correlation between skin test, bronchial provocation test, and histamine release from leucocytes and the serum level of total and allergen-specific IgE in patients atopic to house-dust mite allergen (Dermatophagiodes pteronyssinus) as measured by an intracutaneous skin test. It is concluded that, assuming a positive provocation test to be evidence of allergy, estimation of the allergen-specific IgE concentration in the serum will not offer any major advantages over the intradermal skin test in determining the clinical significance of house-dust mite allergy.

Asthma

[Bronchial antigen provocation tests with the use of whole body plethysmography].

Bronchial provocation tests are performed in order to reproduce the symptoms of extrinsic bronchial asthma. The bronchial obstruction induced hereby can be demonstrated by plethysmographic measurement of specific airway resistance, which is superior to spirometric parameters with regard to sensitivity and effort independence. A rise of specific airway resistance above 20 cmH2O X sec ("dyspnoea threshhold") can be used as the criterium of a positive result. In contrast to forced expiratory manoeuvres no spirometry induced asthma can occur. Automatic evaluation by electronic data processing is possible.

Aerosols

Reaginic bronchial allergy and the occurrence of reagins against mites in a representative sample of a local Swedish population.

This study involves an investigation of 185 subjects, aged 35--54 years, a representative sample of persons with chronic obstructive lung disease in a local Swedish population. Bronchial asthma was diagnosed in 86 persons, chronic bronchitis in 69 and a combination of bronchial asthma and chronic bronchitis in 30. Reaginic bronchial allergy as a provoking factor was considered as definite when the case history, an intracutaneous test, a bronchial provocation test and a radioallergosorbent test were all positive with regard to one and the same allergen. This was found in 28% of the asthmatics. In 16% of the asthmatics, the diagnosis of reaginic bronchial allergy was not supported by all the four diagnostic criteria used but was considered as probable since the case history or the bronchial provocation test was positive in association with a positive RAST or intracutaneous test with the same allergen. Reaginic (IgE) antibodies in serum to mites (Dermatophagoides pteronyssinus) were found in 20 subjects, 18 of whom also had a positive intracutaneous test for house dust. Four of these 20 subjects had definite and 12 had probable reaginic bronchial allergy. One of the remaining four subjects had chronic bronchitis without asthma. The percentage of definite reaginic bronchial allergy may possibly be increased when reliable bronchial provocations with mite allergen can be performed. Increased IgE levels in serum were found in only eight of the 51 asthmatics with reaginic bronchial allergy and in two of the 65 other asthmatics.

Adult

[Occupational asthma].

The diagnosis of occupational asthma requires the integration of a multiplicity of data; the history, cutaneous skin tests, biological tests, respiratory function tests and non-specific tests of bronchial hyperreactivity and specific bronchial provocation test. The history search for the presence of an atopic state, the occurrence of similar disorders in members of the same firm and also the timing of symptoms in relation to the occupational activities. Cutaneous tests are particularly helpful in IgE-mediated asthma in relation to the inhalation of animal or vegetable materials of glycoprotein origin. For haptens, the need for their prior coupling to a protein carrier causes problems which have not been entirely resolved. Laboratory tests run into the same snags. Respiratory function and non-specific bronchial provocation tests, confirm the diagnosis of asthma and enable the medium and long term prognostic to be assessed. Specific bronchial provocation tests are the most appropriate tests to establish an aetiological diagnosis in occupational asthma. Different technical methods are possible: quantitative administration of allergen aerosols, realistic tests, and tests using exposure chambers to achieve true test doses. The products responsible for occupational asthma are multiple. The different substances are characterised in a simplified manner: first animal matter (mammalian and arthropod allergens), secondly substances of vegetable origin (roots, leaves, flowers, grain and flour, wood and its derivates) and finally chemical products. The chemical products are primarily from the pharmaceutical and metal industries and above all from the plastics industry.

Allergens