Although Patau syndrome (Trisomy 13) was first reported cytogenetically in 1960 by Patau, the clinical description of this syndrome dates back as early as 1657 in Bartholin writings. Patau syndrome (Trisomy 13) is a rare chromosomal disorder with an incidence of 1 in 16.000 live births. Trisomy 13 is the third most common autosomal trisomy after trisomy 21 (Down syndrome) and trisomy 18 (Edward syndrome). Most of the cases are due to skull and facial abnormalities; heart, kidney malformations; and/or other physical and mental abnormalities. Most cases are lost in the first days of life, mostly due to severe cardiac anomalies. In this clinical report, a newborn with Patau syndrome with the finding of acalvaria is presented.

Keywords: trisomy 13, Patau syndrome, acalvaria