Autoimmune autonomic ganglionopathy (AAG) occurs when your immune system attacks healthy nerve cells in your autonomic nervous system. It causes symptoms like dizziness or faintness.

Autoimmune autonomic neuropathy (AAG) is a rare condition that’s still poorly understood. It can develop without an apparent cause or after a triggering event. A combination of genetic and environmental factors likely plays a role in its development.

Because of its rarity, there’s no standard treatment for AAG. Doctors often treat AAG with medications and procedures to decrease the activity of your immune system. Some people improve even without treatment.

Read on to learn more about what researchers have discovered so far about this rare disease.

AAG falls into a group of conditions called autonomic neuropathies. These conditions cause dysfunction of your autonomic nervous system. This branch of your nervous system controls bodily functions out of your conscious control such as regulating your:

  • heart rate
  • breathing rate
  • blood pressure
  • sexual arousal
  • digestion

AAG develops when your immune system attacks healthy cells in your autonomic nervous system. It often develops suddenly. In some people, symptoms can get progressively worse over time.

AAG causes difficulties with your autonomic nervous system that can cause a variety of symptoms. The degree of symptoms can range from mild to severe. Some of the most common symptoms include:

Most people experience difficulties with the mobility of food through their gastrointestinal (GI) tract. GI symptoms can include:

Autoimmune conditions develop when cells in your immune system attack healthy nerve cells in your autonomic nervous system. AAG develops when your immune system attacks cells in your autonomic nervous system.

The reason why some people develop AAG is poorly understood. AAG can develop after a triggering event or can develop suddenly, meaning there’s no obvious cause. It most commonly develops in middle-aged women.

People with AAG often develop antibodies that target nicotinic acetylcholine receptors found in bundles of nerve cells in the autonomic nervous system. Antibodies are proteins produced by a type of white blood cell called B cells. They tell other immune cells to attack the molecules bound to the antibodies.

Language matters

You’ll notice that the language used to share stats and other data points is pretty binary, with the use of “women” and “male.”

Although we typically avoid language like this, specificity is key when reporting on research participants and clinical findings.

Unfortunately, the studies and surveys referenced in this article didn’t report data on, or include, participants who were transgender, nonbinary, gender nonconforming, genderqueer, agender, or genderless.

Potential triggers

Many people develop AAG after developing another illness or condition that can affect immune activity.

In a 2022 study, researchers reported a case of a 56-year-old male who developed AAG 35 days after receiving a type of COVID-19 vaccine not approved for use in the United States. The researchers speculated that there might have been a link.

It’s not clear whether COVID-19 and other infections are potential triggers of AAG, but infections seem to be a common trigger for autoimmune diseases in general.

In a 2019 case study, researchers reported a case of AAG developing after a person with melanoma spread to distant locations was treated with the immunotherapy drugs ipilimumab and nivolumab. His symptoms improved when given steroids and intravenous (IV) immunoglobulin but flared up again when his melanoma therapy was restarted.

To start the process of receiving a diagnosis, a doctor will:

  • ask you about your symptoms
  • ask you about your personal and family medical history
  • perform a physical exam

They may then perform other tests such as:

  • urine tests
  • tests to check your heart rate
  • tests to measure your sweat rates
  • tests to measure how quickly your stomach empties
  • blood test to measure levels of g-AChR antibodies

There’s no standard treatment for AAG due to its rarity. Commonly used treatment options include:

  • Plasmapheresis: Plasmapheresis involves removing plasma from your blood and removing harmful antibodies. This can lower the number of autoantibodies circulating through your blood.
  • IV immunoglobulin infusion: An IV immunoglobin infusion gives your body more antibodies to help lower inflammation and potentially lower the autoimmune reaction causing AAG.
  • Corticosteroids through an IV line or orally: Corticosteroids can lower the activity of your immune system to lower the autoimmune reaction causing AAG.
  • Immunosuppressive drugs: Immunosuppressant drugs also work by lowering the activity of your immune system.

In a Japanese study from 2022, 31 people received some combination of the following immunotherapy treatments:

  • methylprednisolone
  • IV immunoglobulin
  • plasmapheresis
  • oral steroids
  • tacrolimus
  • cyclosporine
  • mycophenolate mofetil

The researchers found that people who took these drugs had milder symptoms and fewer overall numbers of symptoms. People who received a combination of treatments had better improvement than people only given one therapy.

More research is needed to fully understand how to best manage AAG.

Researchers haven’t yet developed a cure for AAG, but about a third of people improve without treatment. Recovery may not be complete for all people.

In a 2018 case study, a woman continued to have mild GI symptoms a year after receiving treatment with oral prednisolone. But her condition stabilized without further treatment.

Immunotherapies often need to be repeated to keep the disease activity suppressed.

AAG is a rare autoimmune condition. It’s caused by damage to cells in your autonomic nervous system due to an autoimmune reaction. It can cause symptoms such as low blood pressure when standing or GI symptoms like constipation and bloating.

Researchers haven’t developed a cure for AAG, but your symptoms may improve with treatments such as corticosteroids and immunotherapy. Many people see improvements with these treatments, and about a third of people improve without treatment.