Frey syndrome

A healthy and normally developing girl was born at 41 weeks via forceps-assisted vaginal delivery. Starting around 6 months of age, during meals (and especially when eating sour foods like citrus fruit), she routinely developed acute-onset flushing of the left cheek in a stereotyped linear pattern (Figure 1A and Video S1) and persisting into childhood (Figure 1B). This was not bothersome to her and was not associated with any systemic symptoms. The flushing completely disappeared within 30 min after eating. The Minor starch-iodine test showed no evidence of hyperhidrosis.¹

Auriculotemporal syndrome (“Frey syndrome”) is due to dysfunction of the auriculotemporal nerve (a branch of the mandibular division of the trigeminal nerve, V3). Mechanical injury to the nerve (e.g., during forceps-assisted birth or parotid gland surgery) leads to nerve regeneration with aberrant innervation of the sweat glands of the skin. Thus, activation of the parotid gland during meals induces skin flushing in a V3 distribution. In this patient, anticipatory guidance given to daycare providers helped preempt concerns about food allergies.

The pathophysiology of the syndrome was first described by Dr. Łucja Frey (1889–1942), a Polish physician and scientist who was murdered by the Nazis during World War II.^2-4

Audrey C. Brumback: Conceptualization; investigation; visualization; writing—original draft.

Audrey C. Brumback serves on the editorial board of Annals of the Child Neurology Society.