Pediatric
Chromosomal anomalies
Trisomy 18

Author: Elena Puscasiu, M.D. (see Authors page)

Revised: 19 April 2016, last major update February 2016

Copyright: (c) 2002-2016, PathologyOutlines.com, Inc.

PubMed Search: Trisomy 18 [title] pediatrics

Related: Congenital anomalies general, Trisomy 21, Trisomy 13


Cite this page: Trisomy 18. PathologyOutlines.com website. http://pathologyoutlines.com/topic/pediatrictrisomy18.html. Accessed January 19th, 2017.
Terminology
  • Trisomy 18 syndrome, Edwards syndrome
Essential Features
  • General:
    • Hypoplasia of skeletal muscle and subcutaneous tissue
    • Hypertonicity
  • CNS:
    • Mental deficiency
    • Facial palsy
  • Craniofacial:
    • Prominent occiput
    • Narrow biparietal diameter
    • Short palpebral fissures
    • Small oral opening
    • Narrow palatal arch
    • Micrognathia
  • Ears:
    • Low set
    • Malformed
  • Hands:
    • Clenched hand
    • Overlapping of index finger over third
    • Fifth finger over fourth
  • Feet:
    • Rocker bottom feet
    • Syndactyly of second and third toes
  • Thorax:
    • Short sternum
    • Small nipples
  • Abdominal wall:
    • Inguinal / umbilical hernia
    • Meckel diverticulum
    • Omphalocele
  • Pelvis: small with limited hip abduction
  • Cardiac:
    • Ventricular septal defect
    • Patent ductus arteriosus
    • Atrial septal defect
  • Lung: malsegmentation to absence of right lung
  • Renal:
    • Horseshoe defect
    • Hydronephrosis
    • Polycystic kidney
  • Skin:
    • Cutis marmorata
    • Hirsutism of forehead and back
    • Redundancy
  • Genitalia:
    • Male cryptorchidism
    • Female hypoplasia of labia major
Epidemiology
  • The second most common pattern of human malformation: 0.3 in 1000 newborns
  • 3:1 female to male
Pathophysiology
  • ~80% are due to nondisjunction
Prognostic Factors
  • Most embryos are spontaneously aborted
  • More than 50% die by 2 months of age
  • Almost all die in the first year
Clinical Images

Images hosted on Other server:

Missing Image

Features

Missing Image Missing Image

Clenched overlapping fingers

Missing Image

Facial features

Molecular / Cytogenetics Images

Image hosted on Other server:

Missing Image

Karyotype