Compensatory hyperhidrosis is a form of neuropathy. It is encountered in patients with

myelopathy Myelopathy describes any neurologic deficit related to the spinal cord. The most common form of myelopathy in humans, '' cervical spondylotic myelopathy (CSM)'', also called ''degenerative cervical myelopathy'', results from narrowing of the spina ...

, thoracic disease,

cerebrovascular disease Cerebrovascular disease includes a variety of medical conditions that affect the blood vessels of the brain and the cerebral circulation. Arteries supplying oxygen and nutrients to the brain are often damaged or deformed in these disorders. The ...

, nerve trauma or after surgeries. The exact mechanism of the phenomenon is poorly understood. It is attributed to the perception in the

hypothalamus The hypothalamus () is a part of the brain that contains a number of small nuclei with a variety of functions. One of the most important functions is to link the nervous system to the endocrine system via the pituitary gland. The hypothalamus ...

(brain) that the

body temperature Thermoregulation is the ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is very different. A thermoconforming organism, by contrast, simply adopts the surrounding temperatur ...

is too high. The sweating is induced to reduce body heat. Excessive sweating due to

nervousness Nervous may refer to: * nervousness * Nervous system, a network of cells in an animal's body that coordinates movement and the senses ** Nervous tissue, the cells of the nervous system that work in aggregate to transmit signals Music * "Nervous" ...

anger Anger, also known as wrath or rage, is an intense emotional state involving a strong uncomfortable and non-cooperative response to a perceived provocation, hurt or threat. A person experiencing anger will often experience physical effects, suc ...

, previous

trauma Trauma most often refers to: *Major trauma, in physical medicine, severe physical injury caused by an external source * Psychological trauma, a type of damage to the psyche that occurs as a result of a severely distressing event *Traumatic inj ...

or fear is called

hyperhidrosis Hyperhidrosis is a condition characterized by abnormally increased sweating, in excess of that required for regulation of body temperature. Although primarily a benign physical burden, hyperhidrosis can deteriorate quality of life from a psycholog ...

. Compensatory hyperhidrosis is the most common side effect of

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), faci ...

, a surgery to treat severe

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% an ...

, often affecting just one part of the body. It may also be called ''rebound'' or ''reflex hyperhidrosis''. In a small number of individuals, compensatory hyperhidrosis following sympathectomy is disruptive, because affected individuals may have to change sweat-soaked clothing two or three times a day. According to Dr. Hooshmand, sympathectomy permanently damages the temperature regulatory system. The permanent destruction of thermoregulatory function of the

sympathetic nervous system The sympathetic nervous system (SNS) is one of the three divisions of the autonomic nervous system, the others being the parasympathetic nervous system and the enteric nervous system. The enteric nervous system is sometimes considered part of ...

causes latent complications, e.g., RSD in contralateral extremity. Following surgery for axillary (armpit), palmar (palm) hyperhidrosis (see

) and

blushing Blushing is the reddening of a person's face due to psychological reasons. It is normally involuntary and triggered by emotional stress associated with passion, embarrassment, shyness, fear, anger, or romantic stimulation. Severe blushing ...

, the body may sweat excessively at untreated areas, most commonly the lower back and trunk, but can be spread over the total body surface below the level of the cut. The upper part of the body, above the sympathetic chain transection, the body becomes anhidrotic, where the patient is unable to sweat or cool down, which further compromises the body's

thermoregulation Thermoregulation is the ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is very different. A thermoconforming organism, by contrast, simply adopts the surrounding temperature ...

and can lead to elevated core

temperature Temperature is a physical quantity that expresses quantitatively the perceptions of hotness and coldness. Temperature is measured with a thermometer. Thermometers are calibrated in various temperature scales that historically have relied on ...

, overheating and

hyperthermia Hyperthermia, also known simply as overheating, is a condition in which an individual's body temperature is elevated beyond normal due to failed thermoregulation. The person's body produces or absorbs more heat than it dissipates. When extreme ...

. Below the level of the sympathetic chain interruption, body temperature is significantly lower, creating a stark contrast that can be observed on thermal images. The difference in temperatures between the sympathetically under- and overactive regions can be as high as 10 Celsius.

Variations

Gustatory sweating or

Frey's syndrome 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 responsible for making saliva, and ...

is another presentation of

autonomic neuropathy Autonomic neuropathy (AN or AAN) is a form of polyneuropathy that affects the non-voluntary, non-sensory nervous system (i.e., the autonomic nervous system), affecting mostly the internal organs such as the bladder muscles, the cardiovascular sys ...

. Gustatory sweating is brought on while eating, thinking or talking about food that produces a strong salivary stimulus. It is thought that ANS fibres to

salivary glands The salivary glands in mammals are exocrine glands that produce saliva through a system of ducts. Humans have three paired major salivary glands ( parotid, submandibular, and sublingual), as well as hundreds of minor salivary glands. Salivar ...

have become connected in error with the sweat glands after

nerve regeneration Neuroregeneration refers to the regrowth or repair of nervous tissues, cells or cell products. Such mechanisms may include generation of new neurons, glia, axons, myelin, or synapses. Neuroregeneration differs between the peripheral nervous system ...

. Apart from sweating in the anhidrotic area of the body, it can produce

flushing Flushing may refer to: Places * Flushing, Cornwall, a village in the United Kingdom * Flushing, Queens, New York City ** Flushing Bay, a bay off the north shore of Queens ** Flushing Chinatown (法拉盛華埠), a community in Queens ** Flushing ...

goosebumps ''Goosebumps'' is a series of children's horror fiction novels by American author R. L. Stine, published by Scholastic Corporation, Scholastic Publishing. The protagonists in these stories are tweens or young teens who find themselves in scary ...

, drop of body temperature -

vasoconstriction Vasoconstriction is the narrowing of the blood vessels resulting from contraction of the muscular wall of the vessels, in particular the large arteries and small arterioles. The process is the opposite of vasodilation, the widening of blood ve ...

and

paresthesia Paresthesia is an abnormal sensation of the skin (tingling, pricking, chilling, burning, numbness) with no apparent physical cause. Paresthesia may be transient or chronic, and may have any of dozens of possible underlying causes. Paresthesias ar ...

. Aberrant gustatory sweating follows up to 73% of surgical sympathectomies and is particularly common after bilateral procedures. Facial sweating during salivation has also been described in

diabetes mellitus Diabetes, also known as diabetes mellitus, is a group of metabolic disorders characterized by a high blood sugar level (hyperglycemia) over a prolonged period of time. Symptoms often include frequent urination, increased thirst and increased ...

cluster headache Cluster headache (CH) is a neurological disorder characterized by recurrent severe headaches on one side of the head, typically around the eye(s). There is often accompanying eye watering, nasal congestion, or swelling around the eye on the a ...

, following

chorda tympani The chorda tympani is a branch of the facial nerve that originates from the taste buds in the front of the tongue, runs through the middle ear, and carries taste messages to the brain. It joins the facial nerve (cranial nerve VII) inside the facia ...

injury, and following facial

herpes zoster Shingles, also known as zoster or herpes zoster, is a viral disease characterized by a painful skin rash with blisters in a localized area. Typically the rash occurs in a single, wide mark either on the left or right side of the body or face. ...

. Phantom sweating is another form of autonomic neuropathy. It can be observed in patients with nerve damage (following accidents),

and as a result of sympathectomy. Phantom sweating is a sensation that one is sweating, while the skin remains dry. Affected people can not distinguish whether it is real sweating or just a sensation. The phenomena is experienced in the anhidrotic, denervated area of the body, presenting an abnormal sympathetic nervous system function.

Mechanism

The term 'compensatory' is largely misleading, as it indicates that there is a compensatory mechanism that takes effect after sympathectomy, in which the body 'redirects' the sweating from the palms or face to other areas of the body. Sweating after sympathetic surgery is a reflex cycle between the sympathetic system and the anterior portion of the hypothalamus. Reflex sweating will not happen if hand sweating can be stopped without interrupting sympathetic tone to the human

brain The brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It consists of nervous tissue and is typically located in the head ( cephalization), usually near organs for special ...

. Compensatory hyperhidrosis is aberrant

functioning. The only study evaluating the total body sweat prior and shortly after sympathectomy concluded that patients produce more sweat after the surgery, just not so much in the areas treated by the surgery.

Epidemiology

Of people that have a sympathectomy, it is impossible to predict who will end up with a more severe version of this disorder, as there is no link to gender, age or weight. There is no test or screening process that would enable doctors to predict who is more susceptible.

References

{{reflist Neurological disorders