Airway Response to a Bronchodilator in Healthy Parents of Infants With Bronchiolitis
Bronchiolitis is a viral disease of the lower respiratory tract resulting from inflammatory obstruction of the small airways. It occurs under 2 years of age and is characterized by the acute onset of serous nasal discharge, wheezing, cough, and dyspnea with obstructive pulmonary hyperinflation as seen on a chest roentgenogram.
A significant proportion of infants affected by bronchiolitis have clinical manifestations of asthma later on in childhood. Thus, even if there is no definite link between wheezing in infancy and asthma in childhood, about 30 percent of infants with bronchiolitis are expected to develop asthma.
Respiratory viral infections may be a pivotal component in the pathogenesis of airway hyperresponsiveness and asthma.
Recently, however, some investigators have shown that pre-illness lung function is predictive of subsequent wheezing diseases. Hence, infants who have lower lung function very early in life, before any lower respiratory tract illness, are at higher risk for developing subsequent wheezing illnesses. my canadian pharmacy phone number
It also has been suggested that there may be a genetic predisposition to develop bronchiolitis and that such infants have hyperresponsive airways even before they become infected.’ In this regard, Gurwitz and associates reported a high incidence of bronchial hyperreactivity, as defined by methacholine challenge, in the first-degree relatives of children who had contracted bronchiolitis.
Also, the responsiveness to a bronchodilator drug may be a useful guide to the presence of bronchial reactivity in epidemiologic studies of obstructive airway disease. This test is safe, is relatively inexpensive, and is in widespread use. Indeed, the airway responsiveness to a bronchodilator is tested several times daily in most clinical respiratory function laboratories to assist in the diagnosis of asthma. In addition, recently it has been reported that a significant increase in expiratory airflow following inhalation of a P2-agonist is suggestive of nonspecific airway hyperreactivity in children with normal baseline lung function tests.
Hence, in order to assess the role of genetic factors and environmental influences related to development or persistence of bronchial responsiveness, we have studied the bronchodilator response in healthy parents of infants with bronchiolitis compared with the response in healthy parents of infants who did not have bronchiolitis.
Category: Respiratory Symptoms
Tags: bronchodilator, bronchodilator response, hyperreactivity, hyperresponsiveness, infants bronchiolitis, lung function