The prevalence of children ILD is higher in the younger patients: more than 30% of patients are less than 2 years at diagnosis, as recorded by the recent ERS Task Force. 7% have parental consanguinity and nearly 10% of case siblings were affected by similar diseases. There is a male predominance with a sex ratio of 1.4. The presenting clinical manifestations are often subtle and nonspecific. The onset of symptoms is, in most cases, insidious and many children may have had symptoms for years before the diagnosis of ILD is confirmed. However, the majority of patients has symptoms for less than one year at the time of initial evaluation. The clinical manifestations vary from asymptomatic presentation with radiological features suggestive of ILD to more characteristic presence of respiratory symptoms and signs such as cough, tachypnea and exercise intolerance [9, 60] . These varying presentations are also reflected in the report published by Fan et al. who systematically evaluated the clinical symptoms and physical findings of 99 consecutive children with ILD [2] . Common symptoms at presentation included cough, dyspnea, tachypnea and chest wall retraction, exercise limitation and frequent respiratory infections. Cough is observed in almost 75% of the patients, is normally non-productive and does not disturb sleep. Tachypnea is observed in 80% of patients and is usually the earliest and most common respiratory symptom. Unexplained fever is also reported in almost one third of infants. Failure to thrive (37%), tiring during feeding and weight loss are also common symptoms, mainly in young patients. Although a history of wheezing may be elicited in almost 50% of the patients, wheezing is documented by physical examination in only 20% of the cases.