methacholine challenge

methacholine challenge

[meth′əkō′lēn]
a method of measuring airway activity by an inhalation challenge test. The patient inhales a saline aerosol as a control, followed by increasing concentrations of methacholine chloride, a cholinergic drug. The test is used to confirm the diagnosis of asthma when symptoms are not present. This is a potentially dangerous test and should be performed only by qualified personnel, with resuscitation equipment readily available.
References in periodicals archive ?
Methacholine challenge tests were conducted between 1984 and 2000 using procedures adapted from Chatham et al.
Value of a negative aeroallergen skin-prick test result in the diagnosis of asthma in young adults: Correlative study methacholine challenge testing.
Airway hyper responsiveness was documented by a positive methacholine challenge test.
History and laryngoscopy ruled out asthma in half (13) of the patients mistakenly diagnosed with it; methacholine challenge testing excluded the other half.
A positive response is indicated when there is a 15% reduction in lung function from baseline compared to a 20% fall required by a methacholine challenge test.
In addition, patients with vitamin D concentrations below 30 ng/mL had significantly greater airway hyperresponsiveness to methacholine challenge than patients with adequate vitamin D concentrations.
significant bronchoprotection against methacholine challenge.
The drug also gives a prolonged, dose-dependent protection against inhaled methacholine challenge.
Chest examination revealed diffuse wheezing and a prolonged expiratory phase, and pulmonary function testing with a methacholine challenge confirmed hyperreactive airways.
The primary objective of the trial was to compare the ability of NCX 1020, budesonide and placebo to relax the bronchial smooth muscle of the airways following methacholine challenge (see note 2).