Steroid-Responsive Myeloneuropathy Associated With Antithyroid Antibodies

Background/Objective: To present information about 2 steroid-responsive, antithyroid antibody-positive patients with myeloneuropathy and myelopathy. Methods: Case reports. Results: A 48-year-old woman and a 42-year-old man presented with acute onset tetraparesis and magnetic resonance imaging studies showing cervical spinal lesions. Nerve conduction and biopsy studies of the woman were suggestive of a demyelinating polyradiculoneuropathy. Detailed diagnostic workup turned out to be negative for both patients, except for highly elevated antithyroid antibodies with normal thyroid functions and imaging. Both patients responded remarkably well to high-dose steroid treatment, and their symptoms disappeared in a few months. Both patients' antithyroid antibody levels were reduced shortly after steroid treatment and in parallel with the amelioration of symptoms. Conclusions: Antithyroid antibodies might be associated with acute demyelinating myeloneuropathy or myelopathy pathogenesis and might indicate a good response to steroid treatment in these syndromes.