Children's interstitial and diffuse lung disease.

Children's interstitial and diffuse lung disease (chILD) is a rare heterogenous group of conditions, with symptoms often overlapping with more common conditions, impeding diagnosis and frustrating parents and clinicians alike. Clinical collaborations are improving diagnostic precision, disease phenotyping, mechanistic understanding, and interventional therapeutic capability; however, with over 200 conditions, chILD requires greater aligned international collaboration to address the knowledge gaps. The use of genetics plays an increasing part in diagnosis, and thus might help to align current classification systems. Empirical therapeutics are few, of no proven benefit, and with important side-effects, particularly in infants. Novel therapeutics postulated for several chILD conditions on the basis of mechanistic observations are in development and represent real hope for those conditions to which they apply. Broader therapeutics against the downstream effects (ie, fibrosis) are under consideration for chILD conditions, but require adequately validated biological outcome measures, which the chILD community urgently needs to address.