October 1996 • Volume 31 • Number 10
An unusual case of monozygotic
epigastric heteropagus twinning
Epigastric heteropagus refers to unequal and asymmetric conjoined twins in
which the dependent component (parasite) is smaller and usually attached to the
epigastrium of the dominant component (autosite). Epigastric heteropagus is a
very rare type of conjoined twins. It is generally assumed that conjoined twins
represent a form of monozygotic twinning, but there has been no confirmation of
this monozygotic hypothesis. Epigastric heteropagus twins differ in several ways
from symmetrical conjoined twins. These include male preponderance, and no major
connection of vessels, bowels, or bones. These significant characteristics
suggest to the authors that the fusion of two fertilized ova and the atrophy of
one fetus resulted in this interesting malformation. However, a DNA study
indicated monozygotic origin in their case. The possible pathogenesis was
ischemic atrophy of the body structure of the monozygotic conjoined twins at an
early gestational age.
(J Pediatr Surg 1996 Oct;31(10):1457-60)
- Department of Pediatric Surgery, Yonsei
University College of Medicine, Seoul, Korea.
