Sandbox: Bronchiolitis DD

Diseases	Symptoms	Signs	Diagosis
			Lab tests	Imaging
Bronchiolitis			No specific lab findings Viral tests like ELISA and immunoassays may be done in case of RSV infection. Pulmonary function test is performed to exclude other lung diseases.	No specific imaging findings.
Asthma			Lab tests are not specific for asthma but they are performed to exclude other diseases. Serum examination shows elevated level of esoinophils due to allergy.	CT scan shows dilated bronchi, bronchial wall thickening and air trapping.
COPD
Bacterial pneumonia
Pulmonary embolism
Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia
Influenza
Common cold
Tuberculosis
Interstitial pneumonitis (Hamman - Rich syndrome)
Foreign body aspiration
Sarcoidosis
Pertussis			Nasopharyngeal swab Culture Serology to detect pertussis toxin.	No remarkable imaging findings.

Differential diagnosis of bronchiolitis: Asthma, COPD, sarcoidosis, pneumonia, heart failure, DIPNECH, foreign body inhalation, pulmonary embolism and GERD (in case it is associated with asthma).