(See also Overview of the Autonomic Nervous System.)
Autoimmune autonomic neuropathy is an idiopathic disorder that often develops after a viral infection; onset may be subacute.
Autonomic insufficiency is usually a late manifestation in alcoholic neuropathy.
Other causes can include toxins, drugs, and paraneoplastic syndromes.
Diagnosis of autonomic neuropathy is based on demonstration of autonomic failure and of a specific cause of neuropathy (eg, diabetes, amyloidosis).
Autoimmune autonomic neuropathy may be suspected after a viral infection.
Ganglionic anti–acetylcholine receptor antibody A3 is present in about half of patients with autoimmune autonomic neuropathy and is occasionally present in patients with other autonomic neuropathies.