Autoimmune autonomic ganglionopathy manifesting as acute-onset orthostatic hypotension in a patient undergoing peritoneal dialysis

Orthostatic hypotension is an important complication in the management of patients receiving dialysis therapy. As for the orthostatic hypotension caused by decreased peripheral artery resistance, diabetic neuropathy and amyloidosis are the two main causes of hypotension in dialysis patients. However, some patients develop orthostatic hypotension that is caused by dysfunction of the autonomic nervous system, not by diabetic or amyloidosis-related neuropathy. We herein present a case of a 56-year-old man with a 17-year history of peritoneal dialysis therapy, who developed acute-onset orthostatic hypotension accompanied by hypohidrosis and erectile dysfunction. Because serum autoantibodies to ganglionic nicotinic acetylcholine receptor were detected, he was diagnosed with autoimmune autonomic ganglionopathy (AAG). He was treated with high-dose immunoglobulin therapy (0.6 g per kg of body weight per day) for 5 consecutive days, which resulted in a gradual improvement in dizziness. Two months after the onset of AAG, he could discontinue vasopressors (fludrocortisone acetate and midodrine hydrochloride) and continued maintenance dialysis therapy without the use of vasopressors. This case indicates that physicians should consider autonomic neuropathy including AAG as a differential diagnosis when they encounter dialysis patients with orthostatic hypotension.