Longitudinally extensive transverse myelitis with anti-NMDA receptor antibodies during a systemic lupus erythematosus flare-up

Transverse myelitis (TM) with systemic lupus erythematosus (SLE) has been linked to the presence of autoantibodies (eg, antiaquaporin 4 (AQP4) and anticardiolipin (aCL)) and SLE-induced secondary vasculitis, but the aetiology remains incompletely understood. A 48-year-old Japanese man with a 6-year history of poorly controlled SLE had stopped glucocorticoid therapy 1 year before admission. 3 days before admission, he developed flaccid paraplegia. Spinal MRI showed a longitudinally hyperintense T2 grey matter lesion from the level of Th4 to the conus medullaris, which was considered longitudinally extensive TM (LETM). We administered steroid pulse therapy (methyl-prednisolone 1000 mg/day) for 3 days and prednisolone 50 mg/day. The patient's flaccid paralysis gradually improved. We concluded that the patient's TM was caused by SLE flare-up, even though we could not completely rule out antiphospholipid syndrome. SLE myelitis is relatively rare and many aetiologies are possible for TM in SLE.