Sympathetic nervous system disorders in man.

The sympathetic nervous system innervates most organs in the body and controls their function. A variety of disease processes, surgery or drugs can result in disordered sympathetic nerve function, which can be either localized or more generalized. Malfunction can result in either sympathetic underactivity (causing postural hypotension, impotence or anhidrosis) or overactivity (causing paroxysmal hypertension or hyperhidrosis). The investigation of sympathetic disorders depends upon the system and organs involved and should include, where relevant, investigation of the possible aetiological processes. The clinical features and management of some of the major disorders affecting the sympathetic nervous system, including the recently described syndrome of DBH deficiency, are described.