The following information may help to address your question:
What is aplasia cutis congenita?
Aplasia cutis congenita
is a condition in which there is congenital
(present from birth) absence of skin, with or without the absence of underlying structures such as bone.
It most commonly affects the scalp, but any location of the body can be affected.
While most people with aplasia cutis congenita have no other abnormalities, some people have congenital malformations involving the cardiovascular (heart), gastrointestinal, genitourinary, and central nervous systems.
The cause of this condition is unclear and appears to be multifactorial (many different factors appear to play a role); contributing factors may include teratogens
, trauma, and compromised blood flow to the skin.
Last updated: 9/17/2016
What causes aplasia cutis congenita?
There is no one cause for all cases of aplasia cutis congenita.
The condition is thought to be multifactorial, which means that several factors likely interact to cause the condition.
Factors that may contribute include genetic factors; teratogens (exposures during pregnancy that can harm a developing fetus) such as methimazole, carbimazole, misoprostol, and valproic acid; compromised vasculature to the skin; and trauma.
Some cases may represent an incomplete or unusual form of a neural tube defect
cases of aplasia cutis congenita have been reported.
Cases that appear to be genetic may be inherited
in an autosomal dominant
or autosomal recessive
Last updated: 9/17/2016
What does aplasia cutis congenita commonly look like?
Aplasia cutis congenita is characterized by the absence of a portion of skin in a localized or widespread area at birth. It most commonly (70%) manifests as a solitary defect on the scalp, but sometimes it may occur as multiple lesions. The lesions are noninflammatory and well demarcated, and they range in size from 0.5-10 cm. Aplasia cutis congenita may be circular, oval, linear, or stellate (star-shaped) in configuration.
The appearance varies depending on when the lesion occurred in utero.
Defects in the skin that form early in gestation may heal before delivery and appear as an atrophic, membranous, or parchment-like scar with associated alopecia (absence of hair), whereas less mature defects present as ulcerations. Most lesions occur on the scalp vertex (crown) just lateral to the midline, but defects may also occur on the face, the trunk, or the limbs, sometimes symmetrically. The depth may involve only the epidermis (the outer-most layer of skin) and the upper dermis (the second of the three major layers of skin), resulting in minimal alopecic scarring, or the defect may extend to the deep dermis, the subcutaneous tissue
(fat), or rarely the periosteum, the skull, and the dura.
Last updated: 9/30/2015
What other conditions can be associated with aplasia cutis congenita?
Most patients with aplasia cutis congenita have no other abnormalities, although the condition may be associated with isolated physical anomalies or congenital malformations involving the cardiovascular, gastrointestinal, genitourinary, and central nervous systems.
Larger lesions are more likely to be associated with other defects. Lesions with findings such as vascular flushing, tethering (which may be a sign of a dural attachment), or abnormal surrounding hair may signal further abnormalities and warrant evaluation.
Associated malformation syndromes
may include Opitz
, and oculocerebrocutaneous
, 4p(-), X-p22 microdeletion syndromes
13–15, and chromosome
16–18 defects. Aplasia cutis congenita may also be found in association with an overt or underlying embryologic malformation, such as meningomyelocele
, or spinal dysraphism (one or more vertebrae do not form normally). Aplasia cutis congenita in association with fetus papyraceus
is apparently due to ischemic or thrombotic events in the placenta and fetus. Blistering or skin fragility and/or absence or deformity of nails in association with aplasia cutis congenita is a well-recognized presentation of epidermolysis bullosa
Scalp aplasia cutis congenita lesions may be seen in association with distal limb reduction anomalies (anomalies involving underdevelopment of the ends of the limbs), generally with autosomal dominant inheritance, or sporadically (not inherited) in association with epidermal and organoid nevi (moles on the skin and the organs).
Maternal ingestion of the hyperthyroid drug methimazole or herpes simplex virus or varicella-zoster virus infection in the womb may also be associated with aplasia cutis congenita.
Frieden created a classification system for aplasia cutis congenita consisting of 9 groups based on the number and location of the lesions and the presence or absence of associated malformations. To read more about this classification system, click here.
Last updated: 9/30/2015
What complications can arise with aplasia cutis congenita?
Major complications of aplasia cutis congenita are hemorrhage, secondary local infection, and meningitis
If the defect is small, recovery is uneventful, with gradual growth of the skin and formation of a hairless scar over a period of several weeks. Small bony defects usually close spontaneously during the first year of life. Large or numerous scalp defects may require excision and primary closure if possible, rotation of a flap to fill the defect, or the use of tissue expanders. Trunk and limb defects, despite large size, usually become covered with skin and form atrophic scars.
Last updated: 9/30/2015
Is aplasia cutis congenita inherited?
Not all cases of aplasia cutis congenita are inherited. In order to establish a cause in each case, a detailed history should be done, including a review of maternal medications taken during the pregnancy and evidence of infections such as varicella or herpes viruses. A complete physical examination can be performed to search for associated physical anomalies or recognizable malformation syndromes, some of which may be inherited.
A thorough family history
is very important.
When aplasia cutis congenita is inherited, autosomal dominant inheritance is most common. In this type of inheritance, only one abnormal gene is needed in order for the disease to develop. Often, one of the parents has the disease. An affected person has a 50% chance in each pregnancy to pass along the altered gene. Some cases of aplasia cutis congenita exhibit autosomal recessive inheritance. In this type of inheritance, two copies of an abnormal gene must be present in order for the disease or trait to develop. Typically, an individual with a recessive condition has inherited one altered gene from each of his/her parents (both of whom are carriers and not affected).
If you are concerned about the risks for your children, you may also wish to seek the advice of a genetics professional. This type of medical professional can conduct the aforementioned evaluations and help to determine if your aplasia cutis congenita is inherited. They can also provide you with more specific risks regarding your chances to pass along aplasia cutis congenita to your offspring.
Last updated: 5/12/2016
How can I find a genetics professional in my area?
Last updated: 7/15/2016
We hope this information is helpful. We strongly recommend you discuss this information with your doctor. If you still have questions, please
GARD Information Specialist
Please see our Disclaimer.