Pediatric auriculotemporal nerve (Frey) syndrome.

504 CMAJ, April 2, 2013, 185(6) © 2013 Canadian Medical Association or its licensors A14-month-old boy was referred to the pediatric otolaryngology clinic with recurrent episodes of redness and warmth over his right cheek. The patient had been born at term by an induced vaginal delivery with the assistance of forceps. Shortly after birth, a 5-mm hematoma was seen in front of his right ear, which subsequently resolved. The episodes of facial flushing, each of which lasted for a few minutes, began when the patient was 6 months old and were always triggered by chewing solid foods. There was no history of pruritis, urticaria or other complaints to suggest a food allergy. On examination, we noted a warm erythematous area in front of the patient’s right ear and over his cheek (Figure 1). After consultations with pediatric dermatology and allergy, auriculo temporal nerve syndrome was diagnosed. Auriculotemporal nerve syndrome, also known as Frey syndrome, is an uncommon clinical entity in children. It is widely thought to be the result of aberrant cross-innervation of auriculotemporal nerve fibres following injury to this region. Because both the parasympathetic and sympathetic nerve fibres use acetylcholine neurotransmitters, they can undergo cross regeneration such that impulses to the salivary gland paradoxically stimulate the sweat glands and subcutaneous vessels in the distribution of the au ri culotemporal nerve. Pediatric auriculotemporal nerve syndrome can be characterized clinically as facial erythema and warmth; it is less commonly associated with the production of tears, as is seen in adults. Because the syndrome is believed to be associated with local trauma, operative vaginal deliveries, particularly with the assistance of forceps, may be implicated in the cause of this condition. The condition has also been reported following trauma (e.g., condylar fracture, post seizure) and infection (e.g., herpes zoster). Although long-term follow-up is not well documented in the literature, no proven treatments exist, and spontaneous remission or a dramatic reduction in symptoms has been reported to occur with growth. For this reason, no specific therapy is recommended.