Frey's syndrome (also known as Baillarger's syndrome, Dupuy's syndrome, auriculotemporal syndrome, or Frey-Baillarger syndrome) is a rare neurological disorder resulting from damage to or near the

parotid glands The parotid gland is a major salivary gland in many animals. In humans, the two parotid glands are present on either side of the mouth and in front of both ears. They are the largest of the salivary glands. Each parotid is wrapped around the ma ...

responsible for making saliva, and from damage to the

auriculotemporal nerve The auriculotemporal nerve is a branch of the mandibular nerve (CN V3) that runs with the superficial temporal artery and vein, and provides sensory innervation to various regions on the side of the head. Structure Origin The auriculotempor ...

often from surgery. The symptoms of Frey's syndrome are redness and sweating on the cheek area adjacent to the ear (see

focal hyperhidrosis Focal hyperhidrosis, also known as primary hyperhidrosis, is a disease characterized by an excessive sweating localized in certain body regions (particularly palms, feet and underarms). Studies suggest that this condition, affecting between 1% and ...

). They can appear when the affected person eats, sees, dreams, thinks about or talks about certain kinds of food which produce strong salivation. Observing sweating in the region after eating a

lemon The lemon (''Citrus limon'') is a species of small evergreen trees in the flowering plant family Rutaceae, native to Asia, primarily Northeast India (Assam), Northern Myanmar or China. The tree's ellipsoidal yellow fruit is used for culin ...

wedge may be diagnostic.

Signs and symptoms

Signs and symptoms include

erythema Erythema (from the Greek , meaning red) is redness of the skin or mucous membranes, caused by hyperemia (increased blood flow) in superficial capillaries. It occurs with any skin injury, infection, or inflammation. Examples of erythema not asso ...

(redness or flushing) and sweating in the cutaneous distribution of the

, usually in response to

gustatory The gustatory system or sense of taste is the sensory system that is partially responsible for the perception of taste (flavor). Taste is the perception produced or stimulated when a substance in the mouth reacts chemically with taste receptor ...

stimuli. There is sometimes pain in the same area, often burning in nature. Between attacks of pain there may be numbness or other altered sensations ( anesthesia or paresthesia). This is sometimes termed "gustatory neuralgia".

Causes

Frey's syndrome often results as a complication of surgeries of or near the

parotid gland The parotid gland is a major salivary gland in many animals. In humans, the two parotid glands are present on either side of the mouth and in front of both ears. They are the largest of the salivary glands. Each parotid is wrapped around the ma ...

or due to injury to the auriculotemporal nerve, which passes through the parotid gland in the early part of its course. The auriculotemporal branch of the mandibular branch (V3) of the

trigeminal nerve In neuroanatomy, the trigeminal nerve ( lit. ''triplet'' nerve), also known as the fifth cranial nerve, cranial nerve V, or simply CN V, is a cranial nerve responsible for sensation in the face and motor functions such as biting and chew ...

carries parasympathetic fibers to the parotid salivary gland and

sympathetic fibers The autonomic nervous system (ANS), formerly referred to as the vegetative nervous system, is a division of the peripheral nervous system that supplies internal organs, smooth muscle and glands. The autonomic nervous system is a control system t ...

to the sweat glands of the

scalp The scalp is the anatomical area bordered by the human face at the front, and by the neck at the sides and back. Structure The scalp is usually described as having five layers, which can conveniently be remembered as a mnemonic: * S: The ski ...

. As a result of severance and inappropriate regeneration, the parasympathetic nerve fibers may switch course to a sympathetic response, resulting in "gustatory sweating" or sweating in the anticipation of eating, instead of the normal salivary response. It is often seen with patients who have undergone

endoscopic thoracic sympathectomy Endoscopic thoracic sympathectomy (ETS) is a surgical procedure in which a portion of the sympathetic nerve trunk in the thoracic region is destroyed. ETS is used to treat excessive sweating in certain parts of the body (focal hyperhidrosis), fac ...

, a surgical procedure wherein part of the

sympathetic trunk The sympathetic trunks (sympathetic chain, gangliated cord) are a paired bundle of nerve fibers that run from the base of the skull to the coccyx. They are a major component of the sympathetic nervous system. Structure The sympathetic trunk lies j ...

is cut or clamped to treat sweating of the hands or blushing. The subsequent regeneration or nerve sprouting leads to abnormal sweating and salivation. It can also include discharge from the nose when smelling certain food. Rarely, Frey's syndrome can result from causes other than surgery, including accidental trauma, local infections, sympathetic dysfunction and pathologic lesions within the parotid gland. An example of such rare trauma or localized infection can be seen in situations where a hair follicle has become ingrown, and is causing trauma or localized infection near or over one of the branches of the auriculotemporal nerve.

Diagnosis

Diagnosis is made based on clinical signs and symptoms and a starch-iodine test, also known as the Minor test. The affected area of the face is painted with iodine which is allowed to dry, then dry corn starch is applied to the face. The starch turns blue on exposure to iodine in the presence of sweat.

Treatments

* Injection of botulinum toxin A * Surgical transection of the nerve fibers (a temporary treatment) * Application of an ointment containing an

anticholinergic drug Anticholinergics (anticholinergic agents) are substances that block the action of the neurotransmitter called acetylcholine (ACh) at synapses in the central and peripheral nervous system. These agents inhibit the parasympathetic nervous system ...

such as scopolamine Cochrane reviews of interventions to either prevent or treat Frey's syndrome have found little or no evidence to support their effectiveness or safety, and conclude that further clinical trials are needed.

Epidemiology

The condition is rare, although the exact incidence is unknown. The disorder most often occurs as a complication of the surgical removal of a parotid gland (

parotidectomy A parotidectomy is the surgical excision (removal) of the parotid gland, the major and largest of the salivary glands. The procedure is most typically performed due to neoplasms (tumors), which are growths of rapidly and abnormally dividing cells ...

). The percentage of individuals who develop Frey syndrome after a parotidectomy is controversial and reported estimates range from 30 to 50 percent. In follow-up examinations, approximately 15 percent of affected individuals rated their symptoms as severe. Frey syndrome affects males and females in equal numbers.

History

It is named after Łucja Frey-Gottesman. The disorder was first reported in medical literature by Baillarger in 1853. A neurologist from Poland, Dr. Lucja Frey, provided a detailed assessment of the disorder and coined the term "auriculotemporal syndrome" in 1923.

References

External links

{{Oral pathology Salivary gland pathology Syndromes affecting the nervous system Rare syndromes