Differential diagnosis of wheezing in children. Remarks based on a postgraduate lecture.

In order to differentiate asthma from other disorders resembling it, one should 
attempt to define clearly what we mean by asthma and wheezing. 
A most simplistic statement would define asthma as a recurring form 
of dyspnea marked by wheezing breath sounds. The incompleteness of this 
definition is apparent: asthma is really a symptom complex of labored 
wheezing breathing, characterized by hyperreactivity of the bronchi to various stimuli, 
resulting in generalized narrowing of the airways, variable in scope, and 
often reversible by sympathomimetics, theophylline derivatives, and corticosteroids. A variety of 
conditions must be considered when studying the wheezing child. These include 
asthmatic bronchitis, acute bronchitis, spasmodic croup, allergic cough, habit cough, foreign 
body, cystic fibrosis (mucoviscidosis), right middle lobe syndrome, and upper and 
lower respiratory tract conditions simulating asthma. 