Paediatric interstitial lung disease

Interstitial lung disease (ILD) in children (chILD) is very different in many aspects to the adult disease. First, chILD is rare, estimated at 0.36 per 100,000, compared with 60– 80 per 100,000 for ILD in adults [1]. Secondly, the spectrum of conditions, in particular in infancy, is much wider than in adults. The conditions encompass growth and developmental issues, as well as immunological problems. The consequence is that paediatricians are even less advanced than adult physicians when it comes to making diagnoses by radiology and bronchoalveolar lavage (BAL), and this, combined with the rarity of the conditions, means that there have been no randomised controlled trials of treatment. Thus, chILD is very much work in progress. However, chILD is a really important topic for adult chest physicians; some of the paediatric diseases may in fact present in adult life, and if diagnostic awareness is not heightened, patients may disappear into a dustbin category such as usual interstitial pneumonia (UIP). Furthermore, rare genetic abnormalities may lead to an understanding of modifier genes important in adult ILD. In this regard, it is a pity that recent guidelines saw fit to ignore chILD altogether [2]. This chapter will first review recent advances in the classification of ILD in children, and then discuss presentation, diagnosis and differential diagnosis, as well as what little is known about treatment options.