Aplasia cutis congenita in a setting of fetus papyraceus associated with small fetal abdominal circumference and high alpha-fetoprotein and amniotic acetylcholinesterase.

Fetus papyraceus is the fetal death of one or more fetuses in a multiparous pregnancy. The surviving infants can experience extensive aplasia cutis in an H-shaped distribution over the flanks and abdomen as a consequence of the loss of their fetal sibling. We report the case of a monochorionic, diamniotic pregnancy complicated by a single fetal death at 13 weeks of gestational age. Aplasia cutis of the surviving twin was suggested in utero by three criteria: high amniotic and maternal alpha-fetoprotein, detectable acetylcholinesterase, and small abdominal circumference on prenatal ultrasound. This constellation of findings in the setting of fetus papyraceus can be an indicator of aplasia cutis in the surviving fetus.