Interstitial lung diseases (ILD) in children represent a heterogeneous group of rare and not well defined disorders. Genetic abnormalities of surfactant proteins B (SFTPB) and more recently C (SFTPC) have been shown to be related to these pathologies. However, variability in the lung disease phenotype suggests the involvement of other surfactant-associated genes such as ABCA3 (ATP-binding cassette, sub-family A, member, 3). Thus, the aim of this project is: 1) to assess the prevalence of SFTPC mutation in children with chronic lung diseases, 2) to precise clinical and radiological features of children with SFTPC mutation, and 3) to identify environmental or genetic factors that may explain the extreme variability of this disease.

The first stage of this project will be to constitute a clinical, radiological, biological database of children (1 moth-17 years) with severe respiratory distress and/or an unexplained chronic ILD. Mutations in SFTPC, SFTPB and ABCA3 will be further identified by sequencing and documented with using the parents blood samples.

Inclusion Criteria:

• Children from 1 month to 17 years old with radiological alveola-interstitial syndrome and:
• Oxygen weaning failure > 1 month in term newborn babies(>37th week of PCA)or> 40 weeks of PCA in preterm babies
• or
• Chronic respiratory disease define by chronic hypoxia and/or clinical signs of respiratory distress (cough, retractions, crackle)

Exclusion criteria:

• informed consent denied
• absence of social security

French pulmonary units participating to the study