The first step in dealing with the asthma patient is to make sure it is asthma. Although, many cases of recurrent cough and wheezing in children and adults are due to asthma, other conditions are often misdiagnosed as asthma. In adults, the differential diagnosis of asthma includes
chronic obstructive pulmonary disease (COPD),
chronic bronchitis or emphysema,
congestive heart failure,
gastroesophageal reflux disease,
mechanical obstruction of the airways,
tumor/neoplasm, and
vocal cord dysfunction.
Infrequent causes of wheezing include
pulmonary embolism,
pulmonary infiltrates with eosinophilia, and
some medications (e.g., angiotensin-converting enzyme (ACE) inhibitors) (NHLBI 1997).
In children, chronic cough is a problem, which needs differentiation asthma, or not asthma? Chronic productive cough with purulent sputum is a reason for concern in children and is not usually a symptom of asthma. The younger the child, the more the need to exclude underlying disease at an early stage (de Jongste and Shields 2003).
Wheezing in children can be an allergic (i.e. asthma) or nonallergic response (Lemanske 2003; Weinberger 2003). Nonallergic wheezing in children occurs during acute infections, including viral bronchiolitis. Coughing and wheezing in bronchiolitis is difficult to distinguish from asthma. The differential diagnosis of children with frequent respiratory infection and wheezing should include
airway obstruction with a foreign body,
bronchitis,
pneumonia/bronchiolitis,
cystic fibrosis,
bronchopulmonary dysplasia (in premature infants),