Anhidrosis (overview)L74.4

Complete lack of perspiration. With reduced sweat emission one speaks of hypohidrosis. The boundary to the normal is blurred, as the individual sweat emission is different. An-/hypohidrosis can be congenital or acquired, generalised or localised, temporary or permanent. It can occur reactively due to loss of function in the event of system disorders (e.g. hypothyroidism) or be caused by loss or non-application of the sweat glands ( e.g. in the case of anhidrotic ectodermal dysplasia).

A distinction is made between:

• Anhidrosis without primary skin lesions including:
  • Hypothyroidism
  • Dehydration
  • CNS damage (certain cortical areas, hypothalamus)
  • Pharmaceuticals (atropine, scopolamine, tetraethylammonium)
  • Heat stroke
  • Polyneuropathies
• Anhidrosis in skin diseases with sweat gland disorders:
  • Anhidrotic ectodermal dysplasia
  • Aplasia cutis congenita
  • Ichthyosis
  • Angiokeratoma corporis diffusum
  • Atrophy of the skin
  • Anhidrosis, "thermogenic"
  • Miliaria rubra and Miliaria profunda
  • Miliaria cristallina
  • Angiokeratoma circumscriptum.

Localized forms are usually not noticed, possibly compensatory hypersecretion exists in the areas not affected. Generalized on-/hypohidrosis leads to an increase in temperature with headache, fatigue, feeling of warmth, nausea, tachycardia, hyperventilation when internal or external heat is applied.

Sweat provocation (generalized in warm rooms with high humidity and under physical stress, locally by injection of cholinergic substances), documentation of sweat secretion by Minor sweating test, measurement of skin resistance.

1. Terui T et al (1989) Idiopathic acquired generalized anhidrosis. Dermatologica 178: 123-125
2. Thami GP et al (2003) Acquired idiopathic generalized anhidrosis: a rare cause of heat intolerance. Clin Exp Dermatol 28: 262-264