China
Africa
Explore chapters and articles related to this topic
Asthma Epidemiology, Etiology, Pathophysiology and Management in the Current Scenario
Published in Suvardhan Kanchi, Rajasekhar Chokkareddy, Mashallah Rezakazemi, Smart Nanodevices for Point-of-Care Applications, 2022
Manu Sharma, Aishwarya Rathore, Sheelu Sharma, Kakarla Raghava Reddy, Veera Sadhu, Raghavendra V. Kulkarni
Apart from the lung function test, there are many additional tests to diagnose asthma and these tests include fractional exhaled nitric oxide test, methacholine challenge, X-ray imaging, allergy testing, provocative test for exercise, and cold-induced asthma and sputum test. The fractional exhaled nitric oxide test is a quick, non-invasive test that measures the amount of nitric oxide in exhaled breath. The level of nitric oxide is higher in patients suffering from asthma. In methacholine challenge and allergy testing, the patient is exposed to methacholine which is a direct stimulant of airway smooth muscle and a triggering agent [15,16]. Asthmatic patients would react to methacholine and face mild constriction of airways [14]. Similar to the methacholine test, an allergy test can also be performed by exposing the patient to certain allergens followed by a skin test and blood test. The provocative test for exercise and cold-induced asthma involves testing of exercise and cold bronchoconstriction. The test involves measuring the airway obstruction before and after a patient is subject to rigorous exercise or several breaths of cold air. Apart from this, a simple blood and sputum test can also be used as a confirmatory test. For the blood sample test, a small peg-like device is attached to the finger of a patient and the device measures the amount of oxygen present in the blood. In the sputum test, the patient's sputum or mucus is tested for the presence of eosinophils with the help of eosin dye.
Bronchial Asthma and Idiopathic Pulmonary Fibrosis as Potential Targets for Hematopoietic Stem Cell Transplantation
Published in Richard K. Burt, Alberto M. Marmont, Stem Cell Therapy for Autoimmune Disease, 2019
Júlio C. Voltarelli, Eduardo A. Donadi, José A. B. Martinez, Elcio O. Vianna, Willy Sarti
Bronchial hyperresponsiveness is defined as an increased ability of the airway to narrow its caliber after exposure to nonspecific stimuli, including bronchoconstrictor pharmacologic agonists, such as histamine, acethylcholine, methacoline, and many other stimuli. After nonspecific stimuli provocation, patients presenting with bronchial hyperresponsiveness exhibit a 20% fall in the forced expiratory volume in the first second (FEV1). Usually, the magnitude of airway hyperresponsiveness correlates with the severity of asthma and with variations of the peak expiratory flow rate. An improvement in FEV1 may be observed after the inhalation of bronchodilators. The development of bronchial hyperresponsiveness in asthmatics has been associated with persistent airway inflammation, mainly caused by the activation of inflammatory cells such as mast cells, eosinophils, neutrophils and lymphocytes. Although the mechanisms responsible for airway hyperresponsiveness are not completely understood, the consequences of the persistent inflammation include airway wall thickening, loss of airway epithelium, airway edema, and altered airway smooth muscle function.21
Differences in lung function, bronchial hyperresponsiveness and respiratory health between elite athletes competing in different sports
Published in European Journal of Sport Science, 2023
Guro P. Bernhardsen, Julie Stang, Thomas Halvorsen, Trine Stensrud
In our study, BHR was assessed using a methacholine provocation test. However, eucapnic voluntary hyperpnoea (EVH) is now recommended by the International Olympic Committee -Medical Commission (IOC-MC) and is considered the most specific and sensitive provocation test for BHR in athletes. EVH acts indirectly through the release of inflammatory contractile mediators, and thus suggested to better mimic the trigger factors for EIB in athletes (Hull et al., 2016). Methacholine on the other hand, acts directly on muscarine receptors on the airway smooth muscle cells causing bronchoconstriction, and the test is considered to be similarly sensitive, but less specific than EVH (Boulet & O'Byrne, 2015). Even though EVH has a key role in diagnosing EIB in athletes, the test is not yet recommended as the “gold standard test” due to poor repeatability in mild asthmatic athletes (Hull et al., 2016). Further, as Boulet and O’Byrne state in their review (Boulet & O'Byrne, 2015), athletes may respond differently to different provocation tests, and they therefore suggest that more than one diagnostic test for asthma can be required.