# Extensive Type V Truncal Aplasia Cutis Congenita in a Surviving Twin With Fetus Papyraceus: A Case Report

## TL;DR

A rare case of skin absence in a surviving twin is reported, linked to a deceased co-twin and supporting a vascular disruption theory.

## Contribution

This case report provides a clinical example supporting the vascular disruption hypothesis in type V ACC.

## Key findings

- The patient exhibited classic type V ACC with symmetrical trunk lesions and no systemic abnormalities.
- Conservative treatment led to re-epithelialization and atrophic scarring with a good prognosis.
- The case supports the vascular disruption hypothesis as the primary cause of type V ACC.

## Abstract

Aplasia cutis congenita (ACC) is a rare developmental anomaly characterized by the absence of skin at birth. Type V ACC is a distinct subtype associated with fetus papyraceus—the compressed remnant of a deceased co‐twin—and typically manifests as symmetrical, linear, or stellate lesions involving the trunk and proximal extremities. The proposed mechanism involves ischemic or thromboembolic injury to the surviving twin due to shared placental circulation.

We describe a 30‐day‐old female neonate, the surviving twin of a dichorionic gestation, whose co‐twin was delivered as a fetus papyraceus. The patient presented with extensive, bilaterally symmetrical, linear, and plaque‐like areas of absent skin involving the anterior and posterior trunk. No scalp, limb, or mucosal involvement was observed. Systemic examination and laboratory workup were unremarkable. Based on the characteristic lesion pattern and obstetric history, a diagnosis of type V ACC was established. The patient was treated conservatively with topical calcipotriol and meticulous wound care, leading to progressive re‐epithelialization and residual atrophic scarring.

This case illustrates the classic presentation of type V ACC associated with fetus papyraceus and supports the vascular disruption hypothesis as the predominant pathogenic mechanism. Awareness of this rare entity facilitates early diagnosis, appropriate conservative management, and accurate counseling of parents regarding the excellent prognosis and low recurrence risk.