Genetic Dysfunctions of the Surfactant System in Children: Results of a Multicenter Study

Aim: Genetic, clinical, laboratory-instrumental and morphological characteristics of genetic dysfunctions of the surfactant system in children, therapy and outcomes of the disease. Design: Multicentre, ambispective, open-label, descriptive pilot longitudinal study. Materials and methods. We observed 17 children from 16 families with identified mutations in the SFTPC, ABCA3, NKX2-1 genes. Methods used: genealogical, Sanger sequencing, clinical exome sequencing, computed tomography and histological examination of the lungs. Results. The study included 8 children with congenital deficiency of surfactant protein C, 8 children with brain-lung-thyroid syndrome and 1 patient with congenital deficiency of protein ABSA3. Based on the results of a genetic examination of patients, nucleotide variants c.218T>C were identified in 2 out of 8 patients with a mutation in the SFTPC gene, which is the most common according to the literature. In 5 children, the mutations were hereditary. Congenital deficiency of surfactant protein C, ABCA3 protein and brain-lung-thyroid syndrome were characterized by clinical, computed tomography, and morphological signs of interstitial lung disease. Despite complex respiratory, anti-inflammatory therapy, the frequency of deaths in congenital deficiency of surfactant protein C was 37.5%. Conclusion. Children with severe respiratory distress syndrome of newborns, interstitial lung disease with the development of severe chronic respiratory failure, burdened with a family history should undergo genetic testing to detect mutations in the genes SFTPB, SFTPC, ABCA3. The patient's combination of respiratory symptoms with congenital hypothyroidism and neurological pathology is the basis for genetic examination for NKX2-1 gene mutations to exclude the brain-lung-thyroid syndrome. Keywords: genetic dysfunctions of the surfactant system, congenital deficiency of surfactant protein C, congenital deficiency of ABCA3 protein, brain-lung-thyroid syndrome, NKX2-1 gene, children.