title: [Trisomy 18 syndrome: A case report].
abstract: BACKGROUND
  The trisomy 18 syndrome occurs due to the presence of an extra chromosome 18 in most cases. The prevalence in infants is estimated at 1:6000 to 1:8000. Those affected have a high mortality rate, only 4% may survive their first year of life. There are few reported cases exceeding five years of age.
  
  
  OBJECTIVE
  The aim of this paper is to report a case of trisomy 18 of long survival with oral cavity features not described in the literature, and to provide information to physicians and paediatricians about aetiology, phenotype, survival and genetic counselling.
  
  
  METHODS
  A 7 year-old female patient with 2 karyotypes performed by lymphocyte culture showing 47XX+18 in all metaphases. She presented with growth deficiency, dysmorphic facies, severe psychomotor retardation and cognitive disability, inability to feed, lack of verbal language, sensorineural hearing loss, ataxia, cerebellar hypoplasia, and genitals with hypoplastic labia majora and minora. In the oral cavity: dome shaped palate, macroglossia, absence of upper central incisors and first upper and lower molars in mouth. X-ray findings showed formation of missing teeth, with late eruption being concluded.
  
  
  CONCLUSIONS
  In cases of trisomy 18 syndrome there is an increased risk of neonatal and infant mortality. The clinical characteristics in utero and in neonates have been well described. Since few cases exceeding five years of age have been reported, the phenotype is yet to be established. In the case being reported we describe oral cavity findings not documented in the literature.
authors.affiliation: Ginecólogo y obstetra, Magíster en Ciencias Básicas Medicas, Embriología y Genética, Profesor titular, Escuela de Ciencias Básicas Médicas, Universidad del Valle, Cali, Colombia. Electronic address: saldarriaga@correounivalle.edu.co.
authors.forename: Wilmar
authors.initials: W
authors.lastname: Saldarriaga
authors.affiliation: Estudiante de Pregrado, Escuela de Odontología, Universidad del Valle, Cali, Colombia.
authors.forename: Heidy
authors.initials: H
authors.lastname: Rengifo-Miranda
authors.affiliation: Profesor, Escuela de Ciencias Básicas Médicas, Universidad del Valle, Cali, Colombia.
authors.forename: Julián
authors.initials: J
authors.lastname: Ramírez-Cheyne
mesh_terms: D002648:Child; D002887:Chromosomes, Human, Pair 18; D005260:Female; D006801:Humans; D007621:Karyotyping; D009056:Mouth Abnormalities / Q000235:genetics*; D010641:Phenotype; D013534:Survival; D014314:Trisomy / Q000503:physiopathology*; D000073842:Trisomy 18 Syndrome
keywords: Edward's syndrome; Full trisomy 18; Sobrevida; Survival; Síndrome de Edwards; Síndrome de trisomía 18; Síndrome de trisomía 18 completo; Trisomy 18