Harlequin syndrome is a rare disorder affecting the body's autonomic nervous system, specifically impacting facial flushing and sweating.
Understanding Harlequin Syndrome
Harlequin syndrome, also known as Harlequin sign, is characterized by a distinct, asymmetric flushing and sweating pattern on the face. One side of the face appears normal, while the other exhibits redness (flushing) and may or may not sweat.
Cause
According to references, Harlequin syndrome is a rare dysautonomic syndrome caused by the unilateral blockade of the T2-T3 fibers carrying sudomotor and vasomotor supply to the face. This means there's a disruption in the nerve pathways that control sweating and blood vessel dilation on one side of the face. This disruption often occurs in the T2-T3 thoracic spinal nerves.
Symptoms
The primary symptom is the noticeable difference in color between the two sides of the face, especially during situations that would normally trigger facial flushing, such as:
- Exercise
- Heat exposure
- Emotional stress
One side of the face remains pale, while the other becomes flushed. Sweating may be absent on the flushed side or may be excessive.
Diagnosis
Diagnosis is usually made based on clinical observation of the characteristic facial flushing asymmetry. Further testing may be done to rule out other underlying conditions.
Treatment
Treatment primarily focuses on managing the symptoms. In some cases, treating the underlying cause (if identified) can resolve the syndrome.
Summary
In short, Harlequin Syndrome is a rare condition resulting in uneven facial flushing and sometimes sweating, due to nerve pathway disruptions affecting one side of the face.
