Autonomic neuropathy is a group of symptoms caused by damage to nerves supplying the internal body structures that regulate functions such as blood pressure, heart rate, bowel and bladder emptying, and digestion.

Alternative Names

Neuropathy - autonomic

Causes, incidence, and risk factors

Autonomic neuropathy is a form of peripheral neuropathy affecting the autonomic portion of the peripheral nervous system. The peripheral nervous system includes the nerves used for communication to and from the brain and spinal cord ( central nervous system ) and all other parts of the body, including the internal organs, muscles, skin, and blood vessels. Autonomic neuropathy involves damage to the nerves supplying the autonomic portion of the peripheral nervous system, which is the portion that supplies the internal organs, blood vessels, and other areas not under voluntary (purposeful) control. Damage to the autonomic nerves causes abnormal or decreased function of the areas supplied by the affected nerve. For example, damage to the nerves of the gastrointestinal tract causes decreased ability to move food during digestion (decreased gastric motility), resulting in symptoms such as nausea , vomiting , diarrhea or constipation , and abdominal bloating . Damage to the nerves supplying blood vessels causes problems with regulation of blood pressure and body temperature; dilation of skin capillaries is used to dissipate heat from the body. Damage to other structures causes similar dysfunction. Autonomic neuropathy is a group of symptoms, not a specific disease entity. The causes are multiple. Autonomic neuropathy is associated with the following:

Other forms of neuropathy

Alcoholic neuropathy

Diabetic neuropathy

Parkinson's disease

and other multiple systems atrophy

Disorders involving sclerosis of tissues,

Surgical or traumatic injury to nerves (such as surgical vagotomy, used to control stomach

ulcers and similar disorders)

Use of anticholinergic medications

Signs and tests

Inspection of the abdomen may show distention, and listening to the abdomen with a stethoscope ( auscultation ) may show abnormal sounds indicating decreased gastric motility. An eye examination may show sluggish pupil reaction. Examination by touch ( palpation ) or tapping ( percussion ) may indicate a distended bladder. Blood pressure examination may show a decrease upon standing (postural hypotension ). Occasionally, other symptoms may indicate disturbed functioning of the autonomic nervous system, including high blood pressure , rapid or slow heart rate , irregular heart rhythms, excessive sweating , difficulty swallowing , or other symptoms.

An upper GI (gastrointestinal) examination with small bowel series may show decreased motility, delayed emptying of the stomach, or other abnormalities and may be used to rule out physical obstruction as a cause of

vomiting or other GI symptoms.

An

EGD (esophagogastroduodenoscopy) is used to rule out physical obstruction as a cause of GI symptoms.

An

isotope study may indicate gastroparesis (decreased gastric motility).

A VCUG (

voiding cystourethrogram ) or other tests of bladder function may show a flaccid bladder (inability of the bladder to contract and empty). Other tests for autonomic neuropathy are guided by the suspected cause of the disorder, as suggested by the history, symptoms, and pattern of symptom development.

Treatment

Treatment is supportive. Treatment may need to be chronic and prolonged, and the response to treatment varies. Several treatments may be attempted before a successful treatment is found. The use of elastic stockings and sleeping with the head elevated may reduce postural hypotension . Fludrocortisone or similar medications may be beneficial in reducing postural hypotension for some people. Medications that increase gastric motility (such as Reglan); small, frequent meals; sleeping with the head elevated; or other measures may be used to treat reduced gastric motility. Manual expression of urine (a technique in which the hands are used to compress the bladder), intermittent catheterization, or medications such as bethanechol may be necessary to treat bladder dysfunction. Impotence , diarrhea , constipation , or other symptoms are treated as appropriate. These symptoms may respond poorly to treatment.

Expectations (prognosis)

The outcome varies. If the cause can be identified and treated, there is a chance that the nerves associated with autonomic neuropathy may repair or regenerate. The symptoms may improve with treatment, or they may persist or worsen despite treatment. Most symptoms of autonomic neuropathy are uncomfortable but they are seldom life-threatening.

Complications

Fluid or

electrolyte imbalance such as hypokalemia (if excessive vomiting or diarrhea )

Malnutrition

Kidney failure

(associated with reflux of urine)

Psychologic/social effects of

impotence

Injuries from falls (associated with postural

dizziness )

Calling your health care provider

Call for an appointment with your health care provider if symptoms of autonomic neuropathy occur. Early diagnosis and treatment increases the likelihood of controlling symptoms.

Prevention

Prevention or control of disorders that may be associated with autonomic neuropathy may reduce the risk. For example, diabetics should control blood sugar levels closely. Alcoholics should stop drinking.