Abstract
Fibroblast growth factor 10 (FGF10) is a signaling molecule with a
well-established role for lung branching morphogenesis. Rare
heterozygous, deleterious variants in the FGF10 gene are known
causes of the lacrimo-auriculo-dento-digital (LADD) syndrome as well as
aplasia of lacrimal and salivary glands (ALSG). Previous studies
indicate that pathogenic variants in FGF10 can cause lethal human
developmental disorders of the lung, but reports on diffuse lung disease
caused by pathogenic variants in the FGF10 gene are lacking. We
describe four children with postnatal onset of severe diffuse lung
disease and heterozygous variants in FGF10, each detected by
whole exome or whole genome sequencing. All children presented with
postnatal respiratory failure. Two children died within the first 2 days
of life, one patient died at age of 12 years and one patient is alive at
age of six years, but still symptomatic. One patient presented signs of
severe dental caries suggestive for ALSG or LADD-syndrome.
Histopathological analysis of lung biopies from the two children with
early postpartum demise revealed diffuse developmental disorder
representing acinar dysplasia. Sequential biopsies of the child with
survival until the age of 12 years revealed alveolar simplification and
progressive interstitial fibrosis. Our report extends the phenotype of
FGF10-related disorders to diffuse developmental disorders of the
lung and early onset lung fibrosis. Therefore, FGF10-related
disorder should be considered even without previously described
syndromic stigmata in children with postnatal respiratory distress, not
only when leading to death in the neonatal period but also in case of
persistent respiratory complaints.