Chromosomal anomalies
Trisomy 13

Topic Completed: 1 February 2016

Revised: 30 April 2019

Copyright: 2002-2019,, Inc.

PubMed Search: Trisomy 13 [title] pediatric

Related: Congenital anomalies general, Trisomy 8, Trisomy 9, Trisomy 21, Trisomy 18

Elena Puscasiu, M.D.
Page views in 2019 to date: 94
Cite this page: Puscasiu E. Trisomy 13. website. Accessed November 12th, 2019.
  • Trisomy 13 syndrome, Patau syndrome
  • It occurs in 1 in 5000 live births
  • The risk increases with increasing maternal age
Clinical features
  • CNS: holoprosencephaly, severe intellectual disability
  • Craniofacial: microcephaly, sloping forehead, absent philtrum, cleft lip, cleft palate, cleft tongue, micrognathia
  • Eyes: microphthalmia, colobomata of iris, retinal dysplasia, shallow supraorbital ridges, upslanting, palpebral fissures, absent eyebrows, hypotelorism, anophthalmos, cyclopia
  • Nose: cebocephaly, ethmocephaly / proboscis
  • Ears: abnormal helices
  • Hands: distal palmar axial triradii, narrow hyperconvex fingernails, polydactyly of hands, simian crease
  • Feet: polydactyly of feet
  • Pelvis: hypoplasia
  • Cardiac: ventricular septal defect, patent ductus arteriosus, atrial septal defect, dextroposition
  • Abdominal: omphalocele
  • Renal: polycystic kidney, hydronephrosis, horseshoe kidney
  • Skin: capillary angiomata of forehead, localized scalp defects in parieto-occipital area, loose skin of the posterior neck
  • Genitalia: male cryptorchidism, female bicornuate uterus
Prognostic factors
  • Most embryos with Patau syndrome are spontaneously aborted
  • 73% die by 4 months of age
  • 91% die in the first year of life
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