Transient neonatal autoimmune autonomic ganglionopathy

Autoimmune autonomic ganglionopathy (AAG) is an acquired reversible neuroimmunologic disorder of autonomic ganglia in the sympathetic, parasympathetic, and enteric nervous systems. Antibodies specific for ganglionic nicotinic acetylcholine receptors (gAChRs) impair fast synaptic transmission between preganglionic and postganglionic neurons. Clinical manifestations of AAG reflect peripheral autonomic nervous system dysfunction. Attenuated sympathetic ganglionic transmission produces orthostatic hypotension, low serum catecholamines, and hypohydrosis/anhydrosis. Parasympathetic ganglionopathy causes sicca, gastrointestinal inertia, atonic bladder, tonic pupils, and blunted cardioacceleration. These pandysautonomic symptoms are typically subacute, evolving over days to weeks. Spontaneous improvement may occur but is usually incomplete. Immunomodulatory therapy is often effective, even for chronic symptoms. Transmission of maternal antibodies across the placenta has been described in myasthenia gravis (MG) and systemic lupus erythematosus. Transient and self-limited neonatal symptoms, similar to the maternal disorder, inculpate the antibody as pathogenic and serve as a natural passive transfer experiment. This report describes a case of transient neonatal AAG, further supporting the pathogenicity of gAChR antibodies.