Harlequin Color Change
Harlequin color change can look alarming at first, but it is usually harmless. This phenomenon often appears in newborns when one half of the body turns red while the other half stays pale.
Doctors believe the main cause is the immaturity of the autonomic nervous system, which controls blood vessel movement and skin color. This change often shows up within the first few days of life, especially when a baby is lying on one side. The side facing down may appear flushed, while the opposite side looks lighter. The change is temporary and fades on its own, often within minutes.
While most cases are not linked to illness, harlequin color change can sometimes appear in other contexts, such as certain neurological conditions or issues with blood flow.
Definition of Symptom
Harlequin color change is a temporary skin phenomenon most often seen in newborns. It appears as a sharp color difference between the two halves of the body, usually divided at the midline. One side looks red or flushed, while the other side remains pale.
This presentation is also called the harlequin sign. It is usually harmless and short-lived, often lasting only a few minutes before the skin tone returns to normal. The change may occur when the baby is lying on one side, with the lower side becoming red.
In adults, the term can also relate to symptoms of harlequin syndrome, a rare condition involving changes in skin color and sweating on one side of the face or body. Unlike the newborn color change, this syndrome relates to nerve function.
Key Features of Harlequin Color Change
- A distinct boundary along the body’s midline.
- One side is either red or flushed.
- The other half remained unchanged or appeared pale.
- Usually resolves without treatment.
| Term | Description |
|---|---|
| Harlequin color change | Temporary skin color difference in newborns. |
| Harlequin sign | Visible split of red and pale skin across the body. |
| Harlequin syndrome | Condition with one-sided flushing and sweating. |
Possible Causes/Diseases Condition
Harlequin color change often appears in newborns when one side of the body turns red while the other remains pale. This reaction is usually temporary and linked to immaturity of the autonomic nervous system. It typically resolves on its own as the infant grows.
- Harlequin syndrome is a related but different condition. It happens when the sympathetic nerves on one side of the face or body do not work normally. This leads to one side flushing or sweating while the other side stays unchanged. Triggers may include heat, exercise, or emotional stress.
Some vascular birthmarks can cause skin color differences that look like harlequin changes. Examples include:
- Port-Wine Stain: A flat, reddish mark caused by widened blood vessels.
- Hemangioma of Infancy: A harmless growth of blood vessels that may appear as a raised red area.
- Nascent Hemangioma of Infancy: An early form of hemangioma that starts as a faint mark before developing further.
These vascular conditions differ from harlequin color change because they usually last longer instead of being temporary. However, they may be confused with it in early stages.
| Condition | Key Feature | Typical Course |
|---|---|---|
| Harlequin color change | Temporary half-body color shift | Resolves with age |
| Harlequin syndrome | Asymmetry in flushing/sweating | May persist, rare |
| Port-wine stain | Permanent flat red patch | Persists, may darken |
| Hemangioma of infancy | Raised red growth | Often shrinks over time |
Other Non-Disease Causes
Harlequin color change does not always signal a disease. In many cases, it appears in healthy newborns. Their immature nervous systems can cause sudden shifts in blood vessel tone, leading to one side of the body turning red while the other looks pale.
Changes in body position often trigger this effect. When a baby lies on the side, gravity can influence blood flow, creating a temporary line of color change. This usually fades within minutes without treatment. Anesthesia can also cause this effect. Certain medications used during surgery can affect the autonomic nervous system, producing uneven flushing or sweating on one side of the body. These changes are temporary and fade as the drugs wear off.
Emotional or physical stress can also play a role. Stress may cause uneven vessel dilation, leading to a short-lived harlequin effect. This response is more noticeable in infants but may also occur in adults under strain. In some cases, minor injury or pressure on the skin can bring out a harlequin-like pattern. The effect is usually harmless and clears once circulation returns to normal.
| Non-Disease Cause | Typical Trigger | Duration |
|---|---|---|
| Healthy newborns | Immature vessel control | Seconds to minutes |
| Position changes | Lying on one side | Short, fades quickly |
| Anesthesia | Surgical drugs | Temporary |
| Stress | Emotional or physical strain | Brief |
| Injury/pressure | Local circulation changes | Resolves quickly |
How It Causes the Symptom
Harlequin color change happens when the autonomic nervous system does not send signals evenly to both sides of the face or body. When sympathetic nerves work only on one side, that side flushes and sweats, while the other side stays pale and dry. The clear midline separation makes the contrast very noticeable. Key factors involved include:
- Sympathetic nerve activity → controls blood flow and sweat glands.
- Sudomotor fibers → regulate sweating.
- Vasomotor fibers → control skin blood vessels.
| Side of Body | Effect |
|---|---|
| Intact nerve side | Flushing, sweating |
| Blocked nerve side | Pale, no sweating |
In newborns, the color change may appear due to immature autonomic control. In adults, triggers such as exercise, heat, emotional stress, or spicy food can bring out the symptom. Some treatments, like prostaglandin E1 given to infants with heart conditions, may also influence blood vessel tone and contribute to temporary color changes. The condition usually reflects a localized nerve issue rather than a problem with the skin itself.
Possible Complications
In most newborns, harlequin color change is harmless and resolves without treatment. Episodes are usually brief and do not cause lasting effects. However, in rare cases, the change in skin color may signal an underlying medical condition. These can include issues with the nervous system, circulation, or heart function. Some infants may experience longer or more frequent episodes.
If this occurs, doctors may look for other symptoms such as breathing problems, abnormal heart rate, or poor feeding. In older children or adults, similar one-sided color changes may point to Harlequin syndrome, which is linked to nerve pathway disruption. This can sometimes occur after surgery, trauma, or medical procedures. Possible complications include:
- Misdiagnosis leading to unnecessary testing.
- Anxiety for parents or caregivers.
- Rare association with neurological or cardiovascular disorders.
| Situation | Possible Concern | Action Needed |
|---|---|---|
| Newborn with brief episodes | Usually benign | Observation only |
| Prolonged or frequent changes | Could suggest other illness | Medical evaluation |
| Adult with one-sided flushing/sweating | Possible Harlequin syndrome | Specialist referral |
When to Seek Medical Attention
Harlequin color change in newborns often appears briefly and then fades without treatment. In most cases, it is harmless and linked to temporary changes in blood vessel control. Watch for symptoms that last longer than a few minutes or occur very often. If the skin change does not go away quickly, it may signal another condition. Seek medical care if the baby shows other signs such as:
- Breathing problems
- Feeding difficulties
- Unusual sleepiness or irritability
- Persistent or repeated color changes
In older children or adults, sudden one-sided flushing or sweating may point to Harlequin syndrome, a rare nervous system disorder. Contact a doctor if these changes interfere with daily life or appear with headaches, dizziness, or vision problems.
Seek urgent medical help if symptoms come with severe pain, chest discomfort, weakness, or trouble speaking. These could signal a more serious problem that needs immediate care.
