Differentials
Bronchiolitis
SIGNS / SYMPTOMS
Onset in the first 18-24 months of life. May not have associated atopy. Associated with maternal smoking and acute illness. Sometimes retrospective diagnosis made once the child has left the infantile age range.
Wheeze often accompanied by crackles on auscultation.
INVESTIGATIONS
Suggestive symptoms and a positive test result for causative viruses (e.g., respiratory syncytial virus or parainfluenza viruses).[135]
Episodic (viral) wheeze
SIGNS / SYMPTOMS
Wheeze triggered only by viral infections.
INVESTIGATIONS
None reliable.
Suggestive symptoms and a positive test result for causative viruses are useful.
Inhaled foreign body
SIGNS / SYMPTOMS
History of sudden onset of symptoms such as cough, wheeze, or choking is suggestive. Differential air entry or wheeze exists on auscultation. Chronic symptoms include recurrent episodes of wheeze.
INVESTIGATIONS
Inspiratory and expiratory chest radiographs may reveal asymmetry of chest expansion due to the "ball-valve" mechanism of the foreign body. Chronic changes include collapse and consolidation distal to the obstruction.
Bronchoscopy is necessary for confirmation of the diagnosis and retrieval of the foreign body.
Recurrent aspiration
SIGNS / SYMPTOMS
History of vomiting may be present. Gastroesophageal reflux and swallowing incoordination are risk factors.
Focal signs of pneumonitis or pneumonia may be present on exam acutely during episodes.
Chronic aspiration may be complicated by the development of bronchiectasis (suggested clinically by localized crepitations, decreased air entry, and clubbing).
INVESTIGATIONS
Focal signs of pneumonitis or pneumonia on chest radiography. Chronic changes include those of bronchiectasis (bronchial wall thickening and dilation).
Cardiac failure
SIGNS / SYMPTOMS
Other features of cardiac failure are present (tachycardia, gallop rhythm, or hepatomegaly). Associated with congenital or acquired heart disease.
INVESTIGATIONS
Cardiomegaly and pulmonary edema may be present on chest radiography.
Cystic fibrosis (CF)
SIGNS / SYMPTOMS
Airway inflammation associated with CF may precipitate wheeze, cough, and respiratory distress. CF due to milder mutations may present with difficult-to-control asthma. Asthma may coexist with CF. Failure to thrive may be present.
INVESTIGATIONS
Sweat test: sweat chloride 60 mEq/L or greater on repeat samples is diagnostic (levels of 40-59 mEq/L should be considered as indeterminate and suspicious).[136]
Primary ciliary dyskinesia
SIGNS / SYMPTOMS
Associated with neonatal respiratory distress and recurrent childhood otitis media and sinusitis.
While wheeze may occur, the predominant feature is a daily and year-round chronic moist cough.
An important differential to consider in difficult-to-manage chronic asthma.
50% have situs inversus (Kartagener syndrome).
Signs and symptoms present in the first year of life.
Tracheomalacia
SIGNS / SYMPTOMS
Characterized by expiratory stridor or monophonic expiratory wheeze. Recurrent acute episodes of stridor, wheeze, dyspnea, or cough usually present during the first 2 years of life.
INVESTIGATIONS
Bronchoscopy demonstrating collapse of the trachea during expiration.
Bronchomalacia
SIGNS / SYMPTOMS
Characterized by expiratory stridor or monophonic expiratory wheeze. Recurrent acute episodes of stridor, wheeze, dyspnea, or cough usually present during the first 2 years of life.
INVESTIGATIONS
Bronchoscopy demonstrating collapse of the bronchus during expiration.
Protracted bacterial bronchitis
SIGNS / SYMPTOMS
Bronchitis is characterized by moist cough in combination with wheeze, and may be caused by bacterial or viral infection. Bacterial cause is suggested by purulent lower airway secretions and response to adequate antibiotic course.[131][139]
INVESTIGATIONS
In bacterial bronchitis the sputum culture or bronchoalveolar lavage will most commonly isolate Haemophilus influenzae or Streptococcus pneumoniae.[140]
Vocal cord dysfunction
SIGNS / SYMPTOMS
Paradoxical adduction of the vocal cords during inspiration resulting in high-pitched inspiratory stridor and dyspnea that may be misinterpreted as wheeze. An expiratory component may be present. Typically loudest over the central airways. May be spontaneous or exercise-induced.
INVESTIGATIONS
Exercise testing may reproduce the characteristic symptoms.
Spirometry during an episode demonstrates blunting of inspiratory volume loop.
Hyperventilation
SIGNS / SYMPTOMS
More common in later childhood or adolescence. Associated with anxiety. No associated wheeze on auscultation, and good air entry.
INVESTIGATIONS
No obstructive pattern on spirometry during a hyperventilation episode.
Physiologic exertional dyspnea
SIGNS / SYMPTOMS
Perception of breathlessness during exercise alone.
INVESTIGATIONS
Exercise testing may help distinguish.
Use of this content is subject to our disclaimer