Several authors have demonstrated the presence of antibodies against the HTLV-I retrovirus in patients with MS. Considerable controversy exists regarding the etiologic significance, if any, of this finding, but the presence of these antibodies in the blood or CSF of MS patients has led to reconsideration of that diagnosis in certain cases. It is recommended that, before the diagnosis of MS is changed to that of HTLV-I-associated chronic myelitis, at least 2 of the following abnormalities be present: (1) clinical or electrophysiologic involvement of peripheral nerve or muscle; (2) the presence of oligoclonal bands in the serum; (3) the presence in blood or CSF of lymphocytes with multilobed nuclei; (4) a positive serologic test for syphilis; (5) the presence of a sicca syndrome; and (6) the presence of pulmonary lymphocytic alveolitis.
