Table 1.

Symptoms, lung function alterations, and structural abnormalities at different ages.

	Symptoms	Lung Function	Structural Abnormalities
Toddler	Wheezing	Tidal flow-volume technique Rapid thoraco-abdominal compression technique (RVRTC) ↓Respiratory System Compliance	HRCT Multifocal hyperlucent areas Subpleural opacities
Preschool-age	Wheezing	Forced oscillation technique, multiple breath wash out tests, spirometry if compliant ↓FVC, FEV1, reactance and resistance	HRCT Air trapping Subpleural opacities Mosaic perfusion Peribronchial thickening Emphysema
School-age	Wheezing Cough	Spirometry and DLCO ↑RV, RV/TLC ↓FEV1, FEF25-75, DLCO
Adolescence and adulthood	Breathlessness Wakening with cough Sedentary life Leg discomfort during exercise	Spirometry and DLCO, stress test ↓FEV1, FEF25-75, DLCO Fixed airflow obstruction	HRCT Air trapping Subpleural opacities Bullous disease