(See also Overview of the Autonomic Nervous System Overview of the Autonomic Nervous System The autonomic nervous system regulates physiologic processes. Regulation occurs without conscious control, ie, autonomously. The 2 major divisions are the Sympathetic system Parasympathetic... read more 
.)
The best known autonomic neuropathies are those accompanying peripheral neuropathy due to diabetes Diabetic Neuropathy In patients with diabetes mellitus, years of poorly controlled hyperglycemia lead to multiple, primarily vascular, complications that affect small vessels (microvascular), large vessels (macrovascular)... read more 
, amyloidosis Amyloidosis Amyloidosis is any of a group of disparate conditions characterized by extracellular deposition of insoluble fibrils composed of misaggregated proteins. These proteins may accumulate locally... read more 
, or autoimmune disorders Autoimmune Disorders In autoimmune disorders, the immune system produces antibodies to an endogenous antigen (autoantigen). The following types of hypersensitivity reactions may be involved: Type II: Antibody-coated... read more .
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 Paraneoplastic Syndromes Paraneoplastic syndromes are symptoms that occur at sites distant from a tumor or its metastasis. Although the pathogenesis remains unclear, these symptoms may be secondary to substances secreted... read more 
.
Symptoms and Signs of Autonomic Neuropathies
Common symptoms of autonomic neuropathies include orthostatic hypotension Orthostatic Hypotension Orthostatic (postural) hypotension is an excessive fall in blood pressure (BP) when an upright position is assumed. The consensus definition is a drop of > 20 mm Hg systolic, > 10 mm Hg... read more , neurogenic bladder Neurogenic Bladder Neurogenic bladder is bladder dysfunction (flaccid or spastic) caused by neurologic damage. Symptoms can include overflow incontinence, frequency, urgency, urge incontinence, and retention.... read more , erectile dysfunction Erectile Dysfunction Erectile dysfunction is the inability to attain or sustain an erection satisfactory for sexual intercourse. Most erectile dysfunction is related to vascular, neurologic, psychologic, and hormonal... read more , gastroparesis, and intractable constipation Constipation Constipation is difficult or infrequent passage of stool, hardness of stool, or a feeling of incomplete evacuation. (See also Constipation in Children.) No bodily function is more variable and... read more .
When somatic fibers are involved, sensory loss in a stocking-and-glove distribution and distal weakness may occur.
Diagnosis of Autonomic Neuropathies
Clinical evaluation
Diagnosis Evaluation of Autonomic Insufficiency The autonomic nervous system regulates physiologic processes. Regulation occurs without conscious control, ie, autonomously. The 2 major divisions are the Sympathetic system Parasympathetic... read more 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.
Treatment of Autonomic Neuropathies
Treatment of underlying disorders
Sometimes immunotherapy, plasma exchange, or IV gamma-globulin
Underlying disorders are treated, as are symptoms.
Autoimmune autonomic neuropathy may respond to immunotherapy; plasma exchange or IV gamma-globulin can be used for more severe cases.
Key Points
Diagnose based on identifying symptoms due to autonomic failure (eg, orthostatic hypotension, neurogenic bladder, erectile dysfunction, gastroparesis, intractable constipation) and a cause of neuropathy.
Treat underlying disorders if identified; try immunotherapy if autoimmune autonomic insufficiency is diagnosed or, if symptoms are severe, plasma exchange or IV gamma-globulin.
