[A case of transverse myelitis caused by primary antiphospholipid antibody syndrome].

A 14-year-old man was admitted with sudden onset of paralysis in his lower extremities paralysis and of sensory loss below Th10 level. On admission, linear high intensity signals was seen in the spinal cord from Th 8 to Th 12 level on thoracic MRI T2 weighted image. Laboratory data on admission indicated existence of lupus anticoagrant in the patient's serum. Systemic lupus erythematodes was negative in his past history. The diagnosis of transverse myelitis caused by primary antiphospholipid syndrome was made accordingly. Plasmapheresis was performed to remove the lupus anticoagrant. After plasma pheresis coagulopathy was normalized with disappearance of the lupus anticoagrant. The lesion of the spinal cord is too extensive to be caused by single obstruction of any one blood vessel branch of the spinal cord. The transverse myelitis may be aggravated by the direct invasion of the lupus anticoagrant into nervous tissue from the vasculature whose blood brain barrier had been compromised by intravascular coagulation of this substance.