disorders of autonomic function

Question 1

What is autoimmune autonomic ganglionopathy?

Answer 1

Autoimmune Autonomic Ganglionopathy (AAG) is a rare, immune-mediated condition characterised by subacute pandysautonomia. 50% have auto-antibodies to the ganglionic nicotinic acetylcholine receptor (gAChR), affecting synaptic transmission at autonomic ganglia.

Question 2

What diagnostic tests might you consider for autoimmune autonomic gangliopathy?

Answer 2

Antibody testing- high titers of ganglionic nicotinic acetylcholine receptor (AChR) antibodies in the serum of about 50% of patients

Question 3

What cancer is most commonly associated with autoimmune autonomic ganglionopathy?

Answer 3

paraneoplasticautonomic neuropathymay be clinically indistinguishable from idiopathic AAG until a cancer, usually small-cell carcinoma of the lung, is detected.

Question 4

What are the treatment options for AAG?

Answer 4

seem to benefit from a combination ofplasma exchange, steroids, or IVIG along with chronicimmunosuppressiveagents. Symptomatic therapy fororthostatic hypotensionand constipation should be included. Clinical research to compare the effectiveness of different immunomodulatory therapies is still needed in patients with AAG.

Question 5

How does autoimmune autonomic gangliopathy present?

Answer 5

Autoimmune autonomic ganglionopathyis characterized by an acute-onset widespread sympathetic and parasympathetic failure. Cholinergic deficits are pronounced and include severe impairment ofgastrointestinal motility, withgastroparesisand constipation,bladderretention,dry eyes, anddry mouth. Abnormalpupillary responsesare common.Orthostatic hypotensioncan be severe. There is no motor or sensory impairment.

Question 6

How does AAG tend to progress?

Answer 6

The clinical course of AAG may be monophasic or relapsing. Recovery can take months to years, and prolongedimmunotherapyis required in many patients. Some patients with mild symptoms may improve or recover spontaneously, or with the aid of symptomatic therapies alone.

Question 7

What tests might you do to confirm autonomic dysfunction in AAG?

Answer 7

Pupillometry will show premature pupillary redilation.
quantitative sudomotor axon reflex test (QSART) will be reduced.