RESUMEN
BACKGROUND: Aplasia cutis congenita (ACC) is a heterogeneous condition that can be associated with fetus papyraceus. Few reports exist documenting genetic investigations in ACC or determining the etiology and recurrence risks. OBJECTIVE: We present a Frieden group 5 ACC with fetus papyraceus along with molecular studies. RESULTS: The newborn had multifocal aplasia cutis congenita involving the head, trunk, and limbs with cerebral ischemic changes demonstrated by imaging. The newborn had a monochorionic twin fetus papyraceus. The array cytogenetic analysis was normal. CONCLUSION: Supported by the ischemic cerebral damage, a monochorionic twin fetus papyraceus (monochorionic twins often have vascular anastomoses), and a normal cytogenetic array, this ACC with Frieden group 5 may have resulted from rapid but non-fatal exsanguination of the surviving twin into the dead twin. This type of ACC may have a low recurrence risk.