[A case of subacute myelitis with anti-aquaporin 4 antibody after thymectomy for myasthenia gravis: review of autoimmune diseases after thymectomy].
We report the case of a 60-year-old woman with myasthenia gravis (MG) and Basedow's disease who seven years after thymectomy developed subacute myelitis, a limited form of neuromyelitis optica (NMO). The patient presented with a centrally located long spinal cord lesion (LCL) on cervical cord MRI, anti-aquaporin 4 (AQP4) antibody in serum, and HLA DPB1*0501. Brain MRI showed no specific findings of classic multiple sclerosis (MS). CSF study showed elevated protein (67 mg/dl) but a normal IgG index (0.63) and no oligoclonal IgG bands. After repeated methylprednisolone pulse and immunoadsorption therapies, the T2-high signal lesion shrunk and tetraparesis improved. We reviewed the English and Japanese literature and found reports of 30 patients showing MS including NMO complicated with MG; 27 had been diagnosed as MS after thymectomy. Among these 27, 16 of 17 who were examined by spinal cord MRI and for anti-AQP4 antibodies were NMO. Only one patient with signs and symptoms localized to the optic nerves and spinal cord showed no LCL and was not examined for anti-AQP4 antibodies. In autoimmune disorders of the central nervous system after thymectomy in patients with MG, NMO is more predominant than classic MS.
Kohsaka
Masayuki
M
MS Center, Utano National Hospital.
Tanaka
Masami
M
Tahara
Masayuki
M
Araki
Yasukiyo
Y
Mori
Satoru
S
Konishi
Teturo
T
D051401:Aquaporin 4 / Q000276:immunology*; D001323:Autoantibodies / Q000097:blood*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D009157:Myasthenia Gravis / Q000601:surgery*; D009187:Myelitis / Q000175:diagnosis / Q000276:immunology*; D009471:Neuromyelitis Optica / Q000276:immunology; D011183:Postoperative Complications; D013934:Thymectomy
D051401:Aquaporin 4; D001323:Autoantibodies