Overnight Loss of Pigmented Hair in Autoimmune Autonomic Neuropathy Treated with IVIg

A 34-year-old man with autoimmune autonomic neuropathy associated with high-titer gAChR antibodies experienced selective dark hair loss while being treated with IV immunoglobulin (IVIg). Despite the hair loss, he reported moderate improvement in autonomic symptoms and continued IVIg treatment. The phenomenon, resembling "Marie Antoinette syndrome," was suspected to be related to IVIg, though other factors like stress and autoimmune predisposition could have contributed. The patient showed improvement in autonomic function after additional treatments, but remained without dark hair 5 years later.