Frey's syndrome without hyperhidrosis

Auriculotemporal Frey syndrome not associated with surgery or diabetes: systematic review

Patients who undergo salivary gland, neck, or facelift surgery or suffer from diabetes mellitus often develop Frey syndrome (also known as auriculotemporal syndrome or gustatory sweating). Frey syndrome has been occasionally reported to occur in subjects without history of surgery or diabetes but this variant of Frey syndrome has not been systematically investigated. We searched for original articles of Frey syndrome unrelated to surgery or diabetes without date and language restriction. Article selection and data extraction were performed in duplicate. Our systematic review included 76 reports describing 121 individual cases (67 males and 54 females) of Frey syndrome not associated with surgery or diabetes. The age at onset of symptoms was ≤ 18 years in 113 (93%) cases. The time to diagnosis was 12 months or more in 55 (45%) cases. On the other hand, an allergy evaluation was performed in half of the cases. A possible cause for Frey syndrome was detected in 85 (70%) cases, most frequently history of forceps birth (N = 63; 52%). The majority of the remaining 22 cases occurred after a blunt face trauma, following an auriculotemporal nerve neuritis or in association with a neurocutaneous syndrome. The cause underlying Frey syndrome was unknown in 36 cases.   Conclusion: Frey syndrome not associated with surgery or diabetes almost exclusively affects subjects in pediatric age and is uncommon and underrecognized. Most cases occur after forceps birth. There is a need to expand awareness of this pseudo-allergic reaction among pediatricians and allergists. What is Known: • Pre-auricular reddening, sweating, and warmth in response to mastication or a salivary stimulus characterize Frey syndrome. • It usually occurs after salivary gland surgery and in diabetes. What is New: • In children, Frey syndrome is rare, and most cases occur after a forceps-assisted birth. • In childhood, this condition is often erroneously attributed to food allergy.

Frey Syndrome

OBJECTIVE

To describe the features of Frey syndrome (auriculotemporal nerve dysfunction with gustatory flushing) in childhood.

STUDY DESIGN

A multicenter, retrospective, descriptive observational national case series study was conducted with the help of French academic societies. Diagnostic criteria were based on clinical history, and sometimes also on photographs or provocation tests.

RESULTS

Forty-eight cases were identified, with 2 subtypes: 35 unilateral and 13 bilateral. Associated sweating was reported in only 10% of cases. Diagnosis was made in only 20% of children at the first consultation and inappropriate dietary restriction was prescribed for 21%. Instrumented vaginal delivery was significantly associated with unilateral forms (OR [unilateral vs bilateral] = 29; 95% CI 3.99-311.58; P < .001). The outcome was favorable overall with 57% regression, 20% recovery, and only 23% persistence of initial symptoms. Regression was more frequent in unilateral forms (OR = 6.60; 95% CI 1.23-44.04; P = .016), observed in 69% of unilateral forms at a median age of 27 (24-48) months. Recovery predominated in bilateral forms (OR = 0.05; 95% CI 0-0.38; P = .001), observed in 58% of bilateral cases at a median age of 8 (7-9) months.

CONCLUSIONS

Frey syndrome in childhood is a rare but benign condition with mild symptoms and a favorable outcome in most cases. Unilateral forms are mostly associated with instrumented delivery. Pediatricians should be familiar with this disorder in order to avoid misdiagnosis, mainly as food allergy, and unnecessary referrals and tests.

Infantile Frey's syndrome

Frey's syndrome in children is rare and often erroneously attributed to food allergy. Here we describe a case of Frey's syndrome in an infant and provide a review of the literature. Awareness of this condition is important for the Otolaryngologist in order to avoid unnecessary medical costs and procedures and provide reassurance to both parents and primary care providers in the setting of this benign condition.