[Physiopathologic aspects and clinical pictures in hyperhidrosis].

Fully developed eccrine glands distributed over the entire integument are found only in man. The secretory mechanism is based on the active transport of sodium ions; water diffuses passively following the osmotic gradient. The thermoregulatory center in the hypothalamic region receives impulses from external and internal thermoreceptors and is modified by levels of hormones, by emotions, physical activity and pyrogens. Heat loss is controlled by the blood flow through the skin and by activity of eccrine glands. Thermoregulatory sweating occurs mainly on head and trunk. Emotions trigger eccrine sweating predominantly in the axillae, on palms, and soles. Generalized hyperhidrosis is mostly due to metabolic or endocrinologic disorders; in the state of acclimatization or following menopause hyperhidrosis is conceived to be physiologic. In underlying neurologic disorders hyperhidrosis follows a segmental or irregular pattern. Functional or anatomic eccrine nevi have been described. Gustatory sweating elicited by certain foods is found to be idiopathic and occurs symmetrically on the face. Subsequent to neurologic lesions (e.g., Frey's syndrome) gustatory sweating in segmental distribution may be associated with salivation and can be triggered by any foodstuff. The idiopathic localized hyperhidrosis of axillae, palms, and soles poses a frequent therapeutic problem in the dermatologist's office. Frequently, a familial predisposition is found. To what extent the disorder may be part of a general imbalance of psychovegetative functions is not yet fully understood.