LAUSR

Introduction Partial trisomy 3p results from an unbalanced translocation or de novo duplication. Clinical features include of structural brain abnormalities, dysmorphic facies, congenital heart defects, learning disability and hypoplastic genitalia. We report the clinical manifestations of a case of partial trisomy 3p. Case report The female proband, now 3 years and 9 month female was born to a 33 year old Caucasian mother with 2 neurodevelopmentally normal male children. Intrauterine growth restriction and microcephaly identified antenatally prompted investigation. Fetal MRI at 21 weeks gestation demonstrated dilation of the occipital horn of the right lateral ventricle. Amniocentesis confirmed partial trisomy of chromosome 3 The infant was born at term with no resuscitation or respiratory support required. Echocardiogram revealed a secundum atrial septal defect, muscular ventricular septal defect and a restrictive patent ductus arteriosus. Neonatal MRI demonstrated several structural abnormalities: A parieto–occipital encephalocele measuring 2×3.7 cm containing brain tissue and cerebrospinal fluid Dilation of the occipital horn Bilateral atresia of lateral ventricles Areas of cortical malformation An abnormal corpus callosum Abdominal and hip ultrasound examination were normal. The encephalocele was successfully repaired in the neonatal period. Post operative recovery was complicated by development of hydrocephalus requiring a ventriculo-peritoneal shunt. At 10 and 18 months the patient had seizures related to intercurrent illness and fever. She has never had an afebrile seizure. At present this child is 3 years 9 months with global developmentally delay in all domains. She can walk unaided but has difficulty running. She can use stairs with support but has not progressed to cycling a tricycle. She is visually impaired secondary to a cortical impairment, requiring corrective lenses. She has bilateral sensorineural hearing loss with a cochlear implant. E has remained medically well to this point and has avoided hospital admissions. She requires intensive multidisciplinary involvement by community allied health professionals including physiotherapy, speech and language therapy and occupational therapy. Her parents hope she will be able to access mainstream education with support. Given the rarity of her condition with few reported cases in the medical literature, her long term developmental outcome remains unclear. References Partial 3p trisomy and different rearrangements involving chromosome 3 in the proposita’s family, De Pinto Neto et al, American Journal of Medical Genetics, 1980