Autoimmunity-associated autonomic failure with sympathetic denervation.

We report a case of autoimmunity-associated autonomic failure in a young adult woman who developed arthritis followed 3 years later by pandysautonomia. There was early recovery of parasympathetic functions but persistent neurogenic orthostatic hypotension from post-ganglionic sympathetic denervation. Clinical laboratory testing indicated variable amounts of sympathetic neuronal re-sprouting in the heart, kidneys, eyes, and body as a whole upon follow-up evaluation after 1.5 years.

A Japanese case of autoimmune autonomic ganglionopathy (AAG) and a review of AAG cases in Japan.

A 29-year-old woman presented with acute, pure autonomic (both sympathetic and parasympathetic) failure and positive antibody to ganglionic nicotinic acetylcholine receptor; the diagnosis was autoimmune autonomic ganglionopathy (AAG). She had typical symptoms of AAG, although the patient also had coughing episodes and psychiatric symptoms, which are not typical of AAG in Western countries but are common in AAG cases in Japan. In a review of the Japanese literature, 29 cases of AAG had been reported. AAG patients in Japan were younger and more male predominant than in Western countries. Of the patients in these 29 cases, 10 (34.5%) had coughing episodes and 12 (41.4%) had psychiatric symptoms.

Other autonomic neuropathies associated with ganglionic antibody.

The acetylcholine receptor ganglionic (G-AchR) antibody is a very specific serologic test for autoimmune autonomic ganglionopathy. The spectrum of autoimmune (or presumed to be autoimmune) autonomic disorders, however, is quite broad and positivity to this antibody has been reported in a variety of other conditions, albeit infrequent and with low titer. This review describes the autonomic neuropathies most frequently encountered in clinical practice in which an autoimmune etiology is suspected. They include a chronic form (pure autonomic failure) and limited autonomic neuropathies with predominant involvement of one neurotransmitter type (i.e., cholinergic vs. adrenergic) or one system (such as the gastrointestinal system) or a distal small fiber dysfunction. In each of these conditions, occasional positivity to the G-AchR antibody has been found, but the pathogenetic significance of such finding is still uncertain. Other antigens and antibodies yet to be identified are more likely to be responsible in these disorders.

Clinical laboratory evaluation of autoimmune autonomic ganglionopathy: Preliminary observations.

Several forms of chronic autonomic failure manifest as neurogenic orthostatic hypotension, including autoimmune autonomic ganglionopathy (AAG) and pure autonomic failure (PAF). AAG and PAF are thought to differ in pathogenesis, AAG reflecting decreased ganglionic neurotransmission due to circulating antibodies to the neuronal nicotinic receptor and PAF being a Lewy body disease with prominent loss of sympathetic noradrenergic nerves. AAG therefore would be expected to differ from PAF in terms of clinical laboratory findings indicating post-ganglionic noradrenergic denervation. Both diseases are rare. Here we report preliminary observations about clinical physiologic, neuropharmacologic, neurochemical, and neuroimaging data that seem to fit with the hypothesized pathogenetic difference between AAG and PAF. Patients with either condition have evidence of baroreflex-sympathoneural and baroreflex-cardiovagal failure. Both disorders feature low plasma levels of catecholamines during supine rest, but plasma levels of the other endogenous catechols, dihydroxyphenylalanine (DOPA), dihydroxyphenylacetic acid (DOPAC), and dihydroxyphenylglycol (DHPG), seem to be lower in PAF than in AAG, probably reflecting decreased norepinephrine synthesis and turnover in PAF, due to diffuse sympathetic noradrenergic denervation. PAF entails cardiac sympathetic denervation, whereas cardiac sympathetic neuroimaging by thoracic 6-[(18)F]fluorodopamine scanning indicates intact myocardial sympathetic innervation in AAG.