Alobar holoprosencephaly with cyclopia - autopsy-based observations from one medical center.

Holoprosencephaly, a major congenital malformation of the brain, consists in a complete or partial failure of the prosencephalon to divide into separate hemispheres. Alobar holoprosencephaly with cyclopia was analyzed on the basis of autopsy reports performed for hospitals admitting patients from the Lublin Region in Eastern Poland in the period of 20 years (1981-2000). The malformation was found in seven newborns - five girls, one boy and one child with sex not established due to agenesia of the genital organs, all autopsied in the years 1990-1999. According to clinical data, none of the mothers (age 24-39 years) was exposed to any prescribed or over-the-counter (OTC) drugs during pregnancy, but one was exposed to paints in early pregnancy. The proboscis was present in four of seven cases. Six of seven children displayed additional congenital malformations. In two cases intrapancreatic accessory spleen suggesting trisomy 13 was found. Alobar holoprosencephaly with cyclopia is a rare lethal congenital anomaly frequently accompanied by other malformations and characterized by large variations in incidence.