Hypohidrosis is a disorder in which a person exhibits diminished sweating in response to appropriate stimuli. In contrast with hyp''er''hidrosis, which is a socially troubling yet often benign condition, the consequences of untreated hypohidrosis include hyperthermia, heat stroke and death. An extreme case of hypohidrosis in which there is a complete absence of sweating and the skin is dry is termed anhidrosis.

Causes

Diagnosis

Sweat is readily visualized by a topical indicator such as iodinated starch (

Minor test The Minor test (also known as Minor's test, the starch–iodine test, and the iodine–starch test), described by Victor Minor in 1928, is a qualitative medical test that is used to evaluate sudomotor function (perspiration or sweating). Method T ...

) or sodium alizarin sulphonate, both of which undergo a dramatic colour change when moistened by sweat. A thermoregulatory sweat test can evaluate the body’s response to a thermal stimulus by inducing sweating through a hot box ⁄ room, thermal blanket or exercise. Failure of the topical indicator to undergo a colour change during thermoregulatory sweat testing indicates hypohidrosis, and further tests may be required to localize the lesion.

Magnetic resonance imaging Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to form pictures of the anatomy and the physiological processes of the body. MRI scanners use strong magnetic fields, magnetic field gradients, and radio wave ...

of the brain and ⁄ or spinal cord is the best modality for evaluation when the lesion is suspected to be localized to the central nervous system.

Skin biopsies Skin biopsy is a biopsy technique in which a skin lesion is removed to be sent to a pathologist to render a microscopic diagnosis. It is usually done under local anesthetic in a physician's office, and results are often available in 4 to 10 days. ...

are useful when anhidrosis occurs as part of a dermatological disorder. Biopsy results may reveal the sweat gland destruction,

necrosis Necrosis () is a form of cell injury which results in the premature death of cells in living tissue by autolysis. Necrosis is caused by factors external to the cell or tissue, such as infection, or trauma which result in the unregulated dige ...

or fibrosis, in addition to the findings of the primary dermatological disorder.

Management

The treatment options for hypohidrosis and anhidrosis are limited. Those with hypohidrosis should avoid drugs that can aggravate the condition (see "Medications", under ). They should limit activities that raise the core body temperature and if exercises are to be performed, they should be supervised and be performed in a cool, sheltered and well-ventilated environment. In instances where the cause is known, treatment should be directed at the primary pathology. In autoimmune diseases, such as

Sjögren syndrome Sjögren syndrome or Sjögren's syndrome (SjS, SS) is a Chronic disease, long-term autoimmune disease that affects the body's moisture-producing (lacrimal and salivary) glands, and often seriously affects other organ systems, such as the lungs, k ...

and systemic sclerosis, treatment of the underlying disease using immunosuppressive drugs may lead to improvement in hypohidrosis. In neurological diseases, the primary pathology is often irreversible. In these instances, prevention of further neurological damage, such as good glycaemic control in diabetes, is the cornerstone of management. In

acquired generalized anhidrosis Acquired idiopathic generalized anhidrosis (AIGA) is characterized by generalized absence of sweating without other autonomic and neurologic dysfunction. Other symptoms include Flushing (physiology), facial flushing, Headache, headaches, Dizziness ...

, spontaneous remission may be observed in some cases. Numerous cases have been reported to respond effectively to systemic

corticosteroids Corticosteroids are a class of steroid hormones that are produced in the adrenal cortex of vertebrates, as well as the synthetic analogues of these hormones. Two main classes of corticosteroids, glucocorticoids and mineralocorticoids, are involve ...

. Although an optimum dose and regime has not been established, pulse methylprednisolone (up to 1000 mg/day) has been reported to have good effect.

Citations

General references

* http://www.mayoclinic.com/health/anhidrosis/DS01050 * {{Medical resources , DiseasesDB = 21064 , ICD10 = {{ICD10, L, 74, 4, l, 60 , ICD9 = {{ICD9, 705.0 , MeshID = D007007 Body fluids Excretion Reflexes