A 43-year-old woman who had four recurrences of acute transverse myelitis (ATM) at the fifth thoracic vertebral level in 7 years is reported. Her haematological and immunological abnormalities included antibodies to DNA and nRNP and markedly reduced serum complement during the course of the disease. These findings suggest systemic lupus erythematosus although she had no symptoms other than those of ATM. Methylprednisolone and prednisolone were effective in treating the ATM.