Anhidrosis is a pathology of sweating, in which the secretion of sweat decreases sharply or stops completely. Local disturbance leads to dryness and cracking of the skin, the development of dermatitis; the general is characterized by a disorder of thermoregulation, a decrease in tolerance to physical exertion, severe intoxication. In acute general anhidrosis, the patient should be under the close attention of physicians due to the high probability of violation of vital functions of the body. The diagnosis of anhidrosis is made on the basis of special tests. Treatment of sweating disorder is symptomatic. If possible, the causes of the pathology are eliminated.
ICD 10
L74.4 Anhidrosis
General information
Anhidrosis (Greek. hidros — sweat, an — particle denoting negation) — translated from Greek means “no sweat”. The synonymous name of the disease, which is used in medical literature, is “anidrosis”. Some forms of pathology are named after the researchers who first described them: this is O’Brien’s tropical anhidrosis, Shelley’s deep sweating. Congenital forms of anhidrosis are a rare pathology. For example, pain insensitivity syndrome with anhidrosis is diagnosed in 1-7 out of 100,000 newborns, and patients with Fabry syndrome, which is also characterized by sweating disorders, are only about 5,000 in the territory of the USA. Acute acquired anhidrosis on the background of dehydration is more often diagnosed in the warm season, whereas no noticeable seasonality has been revealed for other forms.
Causes
The basis of the development of the pathological condition is a transient or persistent disruption of the sweat glands. The reason for this may be a violation of the formation of skin appendages at the stage of intrauterine development, the lack of adequate nervous stimulation. The mechanisms of pathology formation are diverse. Anhidrosis is a symptom of a large number of diseases. Most often , the following reasons lead to a violation of sweat secretion:
- Functional disorders of the body. The cessation of sweating is observed with severe dehydration and intoxication. The cause of dehydration is often an insufficient drinking regime in a hot climate. Less often, anhidrosis is a consequence of gastrointestinal disorders and infections, accompanied by vomiting and frequent loose stools, when adequate fluid replenishment is not carried out.
- Hereditary diseases. The pathology of sweating is described in the framework of pain insensitivity syndrome, primary Sjogren’s syndrome, some forms of ectodermal dysplasia. The development of pathology is based on hypoplasia or the absence of sweat glands in the embryonic period.
- Neurological disorders. The activity of sweat glands is regulated by the autonomic nervous system. A change in the nature of sweating may be a consequence of damage to nerve trunks during operations or invasive diagnostic procedures, the development of tunnel neuropathies of the lower and upper extremities, paraneoplastic neurological syndrome, autoimmune and some other diseases.
- Side effect of medications. A sharp decrease in perspiration up to its complete cessation is the result of poisoning with akrikhin, krasavka preparations, a side effect of choline and ganglioblockers. In the first place in terms of the number of cases of anhidrosis are antiepileptic drugs.
- Dermatological diseases and skin lesions. Anhidrosis is observed in scleroderma, chronic atrophic acrodermatitis, ichthyosis. Sweat is reduced in areas of radiation dermatitis, at the site of burns. The degree of local sweating disorder in case of skin damage is determined by the depth of the lesion.
Pathogenesis
Functional disorders during dehydration are associated with loss of blood plasma. A decrease in the volume of circulating blood leads to a decrease in the value of the end-diastolic volume of the ventricles and the systolic volume of the heart. A decrease in cardiac output is accompanied by a reduction in blood flow in the skin and, consequently, sweating.
Anhidrosis is a characteristic symptom of a number of hereditary diseases caused by congenital malformations of the formation of ectoderm derivatives: hair, teeth, sweat glands. Aplasia of sweat glands, their underdevelopment leads to the development of generalized chronic congenital anhidrosis, which persists in the patient throughout life.
Normally, the regulation of sweating is carried out reflexively in response to changes in body temperature, blood and the chemical composition of the internal environment of the body. The centers of thermoregulation are located in the medulla oblongata and hypothalamus. Sympathetic and parasympathetic fibers, each of which innervates a certain area of the skin, depart from the spinal cord at the level of the IV thoracic vertebrae. The disorder can occur at any of the levels of the nervous system. Often, the pathology of excretion develops simultaneously with a violation of sensitivity, less often trophic disorders.
Classification
Anhidrosis is an external manifestation of quite heterogeneous mechanisms of development and symptoms of pathological processes. Individual types of disorders can be grouped according to the causes and forms of the disease. Classification makes it easier for the doctor and the patient to understand the changes taking place, predict complications and the possible outcome of the disease. In clinical dermatology , the following forms of anhidrosis are distinguished:
1 Congenital. It is diagnosed in patients with hypo- or aplasia of the sweat glands. It is often inherited in an autosomal recessive type. Symptoms appear from birth. The course of the disease is chronic. The violation of sweating is generalized. Often, in addition to anhidrosis, other congenital anomalies are observed.
2 Acquired. It develops as a consequence of functional and pathological changes in the body. It is characterized by a variety of clinical manifestations, varying degrees of severity of consequences for the patient’s health. The following forms of acquired anhidrosis are distinguished:
- Sharp. A functional disorder that develops as a result of dehydration, poisoning. It is characterized by severe thermoregulation disorder, pronounced intoxication of the body. Without adequate medical care, there is a high probability of death, irreversible dysfunction of internal organs.
- Chronic. The consequence of violation of vegetative innervation, atrophy of sweat glands. The degree of severity is determined by the area of the skin involved in the pathological process, the quantitative characteristic of the violation of perspiration.
- Tropical. It occurs in countries with hot climates with insufficient fluid intake. It is characterized by vesicular rash, which is not characteristic of other types of anhidrosis. In the genesis of this form of pathology, the role of blockage of the mouths of sweat glands with the smallest particles of sand and dust is great.
- Focal. Anhidrosis develops in a limited area of the face or body. An example of it can be Bernard-Horner syndrome, when ptosis, miosis, enophthalmos and sweating disorders are observed on the side of the lesion. It is characterized by a relatively light current. The patient’s condition is determined by the underlying disease.
- Generalized. The entire area of the skin is affected, and sometimes also the lacrimal glands, the mucous glands of the nasopharynx. The degree of reduction of sweating can vary widely from complete cessation of sweating to a slight decrease.
Symptoms
Congenital anhidrosis
The clinical picture is largely determined by the form of sweating disorders. A patient with congenital anhidrosis may have other developmental abnormalities: lack of hair, deformity of facial bones, change in the shape and number of teeth up to adentia. In such patients, the most difficult period is the period of neonatal and early childhood, when the mechanisms of thermoregulation are imperfect and there is a risk of hyperthermia. In adult patients, the condition is compensated under the condition of restriction of physical activity and adequate drinking regime.
Chronic generalized anhidrosis
It is characterized by increased sensitivity to cold and heat, recurrent hyperthermic episodes with a potential threat to life. The skin of patients is thin and dry with regional hyperkeratosis. Itching, redness, dryness, peeling of the skin of the face, hands, and other exposed areas of the body are permanent with a tendency to worsen in the cold season. Physical activity does not provoke the appearance of perspiration. In more favorable cases, sweat is released, but its amount is not enough to maintain a comfortable body temperature.
In most patients with chronic anhidrosis, pathological changes affect the lacrimal and mucous glands, causing the appearance of “dry eye” syndrome, dryness of the nasopharynx. Insufficient hydration of the eyeball and eyelid mucosa is accompanied by itching, a feeling of “sand in the eyes”, the development of blepharitis and conjunctivitis. Poor humidification of the air when passing through the nasal cavity and nasopharynx can provoke asthma-like symptoms.
Acute generalized anhidrosis
Potentially life-threatening pathology. Within a short time, the patient’s condition worsens to severe and extremely severe. The heart rate increases, breathing becomes faster. Due to the rapid accumulation of metabolic products and mineral salts, diuresis increases, the work of the gastrointestinal tract is disrupted. Appetite is reduced. With dehydration, thirst can be excruciating.
If the cause of the development of acute generalized anidrosis is a disease, then there may not be thirst. The increase in body temperature associated with anhidrosis increases due to increasing intoxication. Violation of well-being, functioning of organs and body systems develops so quickly that the examination and correction of the patient’s condition is carried out in the intensive care unit.
Local anhidrosis
The local form does not affect the general condition of the patient. The skin at the site of the lesion flakes off, sometimes cracks, but more often it is possible to detect changes only when conducting diagnostic tests during a comprehensive examination for other symptoms present in the patient.
Complications
In newborns with undiagnosed anhidrosis, hyperthermia leads to brain damage and death. In early childhood, every third child with anhidrosis dies from poorly controlled temperature rise against the background of an infectious disease.
A characteristic complication of acute generalized anhidrosis is a violation of the liver and kidneys. The load on these organs increases with increasing intoxication, which in the long term may lead to chronic insufficiency. Blood thickening due to the loss of a large volume of plasma, a compensatory increase in heart rate can cause the development of heart failure.
Diagnostics
It is not difficult to detect a violation of sweating. It is much more difficult to determine the type of disorder and the cause of anhidrosis. When examining a patient, an integrated approach is used, which is based on laboratory and functional tests, consultations of related specialists: neurologist, endocrinologist, geneticist. The survey plan includes:
- Study of the structure of the skin and its appendages. Methods of histological examination of the skin, confocal microscopy or graphite palm/foot prints allow to confirm the presence or absence of sweat glands. These methods are used when a patient is suspected of having genetic diseases, one of the manifestations of which is anhidrosis.
- Quantitative methods for assessing sweating. The functioning of the sweat glands is assessed by the results of the pilocarpine-induced sweat formation test. The introduction of pilocarpine normally enhances the production of sweat. Depending on the severity of the disorders, the amount of fluid secreted by the skin can be significantly reduced or completely absent. The method is used to identify generalized and limited forms of pathology.
- Genetic tests. They are carried out in order to confirm a suspected hereditary disease. They allow you to make an accurate diagnosis, determine the prognosis for the health and life of the patient. In adult patients, according to the results of tests, the geneticist makes a forecast regarding the probability of transmission of the identified genetic disorders to children.
Anhidrosis treatment
Hereditary forms of pathology require constant correction. In patients with acquired forms of anhidrosis, it is advisable to identify and eliminate the cause of the pathology. Chronic sweating disorder and its consequences are the area of interest of a dermatologist. The identification and treatment of diseases that have caused the development of anidrosis is within the competence of narrow specialists of various specialties.
The patient is recommended to wear closed clothes to protect the skin from exposure to ultraviolet radiation, dry air, wind. Special lotions and creams help to normalize the level of skin hydration. Any thermal procedures are prohibited. It is recommended to limit physical activity, avoid being outdoors in hot weather. With the development of a hyperthermic episode, it is necessary to take the patient to the hospital as soon as possible.
Prognosis and prevention
Timely diagnosis and adequate treatment make it possible to avoid complications of the disease and reduce the patient’s life expectancy. In infants with anhidrosis, it is necessary to control body temperature, uncontrolled thermal exposure is unacceptable. In older children and adults, the use of soft drinks, moisturizing clothes, the use of special cooling vests and hats helps to avoid hyperthermia.
