Neonatal osteosclerotic bone dysplasia (Raine syndrome)

Background: Raine syndrome is a rare autosomal recessive neonatal osteosclerotic bone dysplasia caused due to mutations in the FAM20C gene. It has an early and aggressive onset which often results in death in the first few weeks of life, although there have been cases of patients surviving into childhood. Clinical Description: We describe the case of a neonate girl born with microcephaly, proptosis, triangular mouth, depressed flat nasal bridge, mid-face hypoplasia, low set ears, high-arched palate, and a wide-open anterior fontanelle. Based on the clinical phenotype, the differentials considered were a congenital infection and Crouzon syndrome. Management: Infantogram revealed generalized osteosclerosis. Based on the radiological phenotype, the differentials considered include Thanatophoric dysplasia, osteopetrosis, and Achondroplasia. Search for concealed anomalies revealed dysmorphic features in the brain and kidneys. The clinical exome demonstrated a heterozygous missense and heterozygous nonsense variant in exon-7 of the FAM20C gene, which established the diagnosis of Raine syndrome. Conclusion: Genetic analysis based on phenotype can aid in the early diagnosis of dysmorphic children and help in instituting appropriate management