Neurological aspects of anhidrosis: differential diagnoses and diagnostic tools

Abstract

Anhidrosis refers to the condition in which the body does not respond appropriately to thermal stimuli by sweating. Sweating plays an important role in maintaining the body temperature, and its absence should not be overlooked since an elevated body temperature can cause various symptoms, even leading to death when uncontrolled. The various neurological disorders that can induce anhidrosis make a detailed neurological evaluation essential. The medication history of the patient should also be checked because anhidrosis can be caused by various drugs. The tests available for evaluating sweating include the quantitative sudomotor axon reflex sweat test, thermoregulatory sweat test, sympathetic skin response, and electrochemical skin conductance. Pathological findings can also be checked directly in a skin biopsy. This review discusses the differential diagnosis and evaluation of anhidrosis.