Hyperhidrosis

Hyperhidrosis is the condition characterized by abnormally increased perspiration, in excess of that required for regulation of body temperature.

Classification
Hyperhidrosis can either be generalized or localized to specific parts of the body. Hands, feet, armpits, and the groin area are among the most active regions of perspiration due to the relatively high concentration of sweat glands; however, any part of the body may be affected.

Hyperhidrosis can also be classified depending by onset, congenital or acquired. Primary hyperhidrosis is found to start during adolescence or even before and seems to be inherited as an autosomal dominant genetic trait. Primary hyperhidrosis must be distinguished from secondary hyperhidrosis, which can start at any point in life. The latter form may be due to a disorder of the thyroid or pituitary gland, diabetes mellitus, tumors, gout, menopause, certain drugs, or mercury poisoning.

Hyperhidrosis may be also divided into palmoplantar (symptomatic sweating of primarily the hands or feet), gustatory and generalized hyperhidrosis.

Alternatively, hyperhidrosis may be classified according to the amount of skin that is affected and its possible causes. In this approach, excessive sweating in an area that is greater than 100 cm2 (up to generalized sweating of the entire body) is differentiated from sweating that affects only a small area.

Cause
The cause of primary hyperhidrosis is unknown, although some surgeons claim that it is caused by sympathetic overactivity. Nervousness or excitement can exacerbate the situation for many sufferers. Other factors can play a role; certain foods and drinks, nicotine, caffeine, and smells can trigger a response.

A common complaint of patients is that they get nervous because they sweat, then sweat more because they are nervous.


 * Hyperhidrosis of a relatively large area (>100 square cm or generalized)
 * In people with a past history of spinal cord injuries
 * Autonomic dysreflexia
 * Orthostatic hypotension
 * Posttraumatic syringomyelia
 * Associated with peripheral neuropathies
 * Familial dysautonomia (Riley-Day syndrome)
 * Congenital autonomic dysfunction with universal pain loss
 * Exposure to cold, notably associated with cold-induced sweating syndrome
 * Associated with probable brain lesions
 * Episodic with hypothermia (Hines and Bannick syndrome)
 * Episodic without hypothermia
 * Olfactory
 * Associated with intrathoracic neoplasms or lesions
 * Associated with systemic medical problems
 * Pheochromocytoma
 * Parkinson's disease
 * Thyrotoxicosis
 * Diabetes mellitus
 * Congestive heart failure
 * Anxiety
 * Menopausal state
 * Due to drugs or poisoning
 * Night sweats
 * Compensatory
 * Associated with toxins
 * Infantile acrodynia induced by chronic low-dose mercury exposure, leading to elevated catecholamine accumulation and resulting in a clinical picture resembling pheochromocytoma.


 * Hyperhidrosis of relatively small area (<100 square cm)
 * Idiopathic unilateral circumscribed hyperhydrosis
 * Reported association with:
 * Blue rubber bleb nevus
 * Glomus tumor
 * Fumblitis
 * POEMS syndrome
 * Burning feet syndrome (Goplan's)
 * Trench foot
 * Causalgia
 * Pachydermoperiostosis
 * Pretibial myxedema
 * Gustatory sweating associated with:
 * Encephalitis
 * Syringomyelia
 * Diabetic neuropathies
 * Herpes zoster (shingles)
 * Parotitis
 * Parotid abscesses
 * Thoracic sympathectomy
 * Auriculotemporal or Frey's syndrome
 * Miscellaneous
 * Lacrimal sweating (due to postganglionic sympathetic deficit, often seen in Raeder's syndrome)
 * Harlequin syndrome
 * Emotional hyperhydrosis

Treatment
Hyperhidrosis can often be very effectively managed.

miraDry
miraDry is a new procedure of non-invasive delivery of controlled electromagnetic energy to the region where the sweat glands reside. The energy generates heat which results in thermolysis of the sweat glands. At the same time, a continuous hydro-ceramic cooling system protects the superficial dermis and keeps heat at the level of the sweat glands. Because sweat glands do not regenerate after treatment, the results are lasting.

Medications
Aluminium chloride is used in regular antiperspirants. However, hyperhidrosis sufferers need solutions with a much higher concentration to effectively treat the symptoms of the condition. These antiperspirant solutions are especially effective for treatment of axillary hyperhidrosis. Normally it takes around three to five days to see the results. The main secondary effect is irritation of the skin. For severe cases of plantar and palmar hyperhidrosis there is some success using conservative measures such as aluminium chloride antiperspirants.

Injections of botulinum toxin type A, going by the brand name of Botox or Dysport, are used to disable the sweat glands. The effects can last from 4–9 months depending on the site of injections. This procedure used for underarm sweating has been approved by the U.S. Food and Drug Administration (FDA).

Several anticholinergic drugs reduce hyperhidrosis. Oxybutynin (brand name Ditropan) is one that has shown promise. although it has important side effects, which include drowsiness, visual symptoms and dryness in the mouth and other mucous membranes. A time release version of the drug is also available (Ditropan XL), with purportedly reduced effectiveness. Glycopyrrolate (Robinul) is another drug used on an off-label basis. The drug seems to be almost as effective as oxybutynin and has similar side-effects. Other anticholinergic agents that have been tried include propantheline bromide (Probanthine) and benztropine (Cogentin).

Antidepressants and anxiolytics were formerly used on the belief that primary hyperhidrosis was related to an anxious personality style.

Surgical procedures
Sweat gland removal or destruction is one surgical option available for axillary hyperhidrosis. There are multiple methods for sweat gland removal or destruction such as sweat gland suction, retrodermal currettage, and axillary liposuction, Vaser, or Laser Sweat Ablation. Sweat gland suction is a technique adapted from liposuction, in which approximately 30% of the sweat glands are removed, with a proportionate reduction in sweat.

The other main surgical option is endoscopic thoracic sympathectomy (ETS), which cuts, burns, or clamps the thoracic ganglion on the main sympathetic chain that runs alongside the spine. Clamping is intended to permit the reversal of the procedure. ETS is generally considered a "safe, reproducible, and effective procedure and most patients are satisfied with the results of the surgery". Satisfaction rates above 80% have been reported, and are higher for children. The procedure causes relief of excessive hand sweating in about 85-95% of patients. ETS may be helpful in treating axillary hyperhidrosis, facial blushing and facial sweating; however, patients with facial blushing and/or excessive facial sweating experience higher failure rates, and patients may be more likely to experience unwanted side effects, although this has not been established in a controlled trial or independent study.

ETS side effects have been described as ranging from trivial to devastating. The most common secondary effect of ETS is compensatory sweating. Major drawbacks related to compensatory sweating are seen in 20-80%. Most people find the compensatory sweating to be tolerable while 1-51% claim that their quality of life decreased as a result of compensatory sweating." Total body perspiration in response to heat has been reported to increase after sympathectomy.

Additionally, the original sweating problem may recur due to nerve regeneration, sometimes within 6 months of the procedure.

Other side effects include Horner's Syndrome (about 1%), gustatory sweating (less than 25%) and on occasion very dry hands (sandpaper hands). Some patients have also been shown to experience a cardiac sympathetic denervation, which results in a 10% lowered heartbeat during both rest and exercise; leading to an impairment of the heart rate to workload relationship.

Lumbar sympathectomy is a relatively new procedure aimed at those patients for whom endoscopic thoracic sympathectomy has not relieved excessive plantar (foot) sweating. With this procedure the sympathetic chain in the lumbar region is clipped or divided in order to relieve the severe or excessive foot sweating. The success rate is about 90% and the operation should be carried out only if patients first have tried other conservative measures. This type of sympathectomy is also controversial, as patients undergoing the procedure often end up with hypotension, (a sign of autonomic dysfunction), and in males retrograde ejaculation (male infertility) and inability to maintain erection has been reported. New information has become available and shown that the issues of retrograde ejaculation, inability to maintain erection and hypertension are not validated. In separate 2007 and 2010 papers none of the patients experienced sexual dysfunction.

Percutaneous sympathectomy is a related minimally invasive procedure in which the nerve is blocked by an injection of phenol. The procedure allows for temporary relief in most cases. Some medical professionals advocate the use of this more conservative procedure before the permanent surgical sympathectomy.

Other
Iontophoresis was originally described in the 1950s, and its exact mode of action remains elusive to date. The affected area is placed in a device that has two pails of water with a conductor in each one. The hand or foot acts like a conductor between the positively- and negatively-charged pails. As the low current passes through the area, the minerals in the water clog the sweat glands, limiting the amount of sweat released. Some people have seen great results while others see no effect. The device can be painful (pain is usually limited to small wounds and over time the body adjusts to the procedure) and the process is time-consuming. The device is usually used for the hands and feet, but there has been a device created for the axillae (armpit) area and for the stump region of amputees.

Hypnosis has been used with some success in improving the process of administering injections for the treatment of hyperhidrosis. Absorbent shoe insoles decrease the sweat in shoes. Relaxation and meditation and weight loss have also been proposed to be of help.

Prognosis and impact
Hyperhidrosis can have physiological consequences such as cold and clammy hands, dehydration, and skin infections secondary to maceration of the skin. Hyperhidrosis can also have devastating emotional effects on one’s individual life.

Affected people are constantly aware of their condition and try to modify their lifestyle to accommodate this problem. This can be disabling in professional, academic and social life, causing embarrassments. Many routine tasks become impossible chores, which can psychologically drain these individuals.

Excessive sweating of the hands interferes with many routine activities, such as securely grasping objects. Some hyperhidrosis sufferers avoid situations where they will come into physical contact with others, such as greeting a person with a handshake. Hiding embarrassing sweat spots under the armpits limits the sufferers' arm movements and pose. In severe cases, shirts must be changed several times during the day. Additionally, anxiety caused by self-consciousness to the sweating may aggravate the sweating. Excessive sweating of the feet makes it harder for patients to wear slide-on or open-toe shoes, as the feet slide around in the shoe because of sweat.

Some careers present challenges for hyperhidrosis sufferers. For example, careers that require the deft use of a knife may not be safely performed by people with excessive sweating of the hands. Those in careers that require federal background checks (such as education), may encounter difficulty with some methods of fingerprint scanning used by law enforcement agencies. Employees, such as sales staff, who interact with many new people can be negatively affected by social rejection. It is extremely frustrating whenever a sufferer touches or holds something on the sales display, it has to be wiped clean each and everytime they come in contact with it as it leaves a lot of sweat marks. The risk of dehydration can limit the ability of some sufferers to function in extremely hot (especially if also humid) conditions. Even the playing of musical instruments can be uncomfortable or difficult because of sweaty hands.

Epidemiology
Primary hyperhidrosis is estimated at 2.8% of the population of the United States. It affects men and women equally, and most commonly occurs among people aged 25–64 years. Some may have been affected since early childhood. About 30–50% have another family member afflicted, implying a genetic predisposition.

In 2006, researchers of Saga University in Japan reported that primary palmar hyperhidrosis locus maps to 14q11.2-q13.