Smith–magenis syndrome. A unique neonatal presentation among the Arab population

Abstract

Smith–Magenis Syndrome (SMS) is a rare multisystem genetic disorder caused by a heterozygous deletion of or a heterozygous pathogenic variant in RAI1 on chromosome 17p11.2. characterized by the variable intellectual deficit, sleep disturbance, brachycephaly, midface hypoplasia, prognathism, hoarse voice, speech delay with or without hearing loss, psychomotor and growth retardation, cutaneous features, and behaviour problems. Our reported case is a term newborn diagnosed antenatally in the feto-maternal unit to have large multi-cystic dysplastic left kidney and unilateral cerebralventriculomegaly. The genetic disorder was suspected due to symmetric IUGR and dysmorphic features. Chromosomal micro-array confirmed the diagnosis of Smith-Magenis Syndrome.MRI brain confirmed Dandy-Walker spectrum malformation. Ultrasound abdomen showed left multi-cystic dysplastic kidney. Smith-Magenis Syndrome is usually diagnosed in childhood and little is known about its presentation in neonates especially in the Arab population. Our patient presented with Intra-cranial haemorrhage, seizures, thrombocytopenia, feeding difficulty, hypoglycemia and acute kidney injury; which all resolve before discharge.