Inflammatory demyelinating peripheral neuropathies associated with human T‐cell lymphotropic virus type III infection

Nine patients with inflammatory demyelinating polyneuropathies (IDP) were found to have human T‐cell lymphotropic virus type III (HTLV‐III) infection. The 8 men, 6 of whom were homosexual, and 1 woman, a former intravenous drug user, presented with progressive weakness. Two had lymphadenopathy but all were otherwise asymptomatic. Six had chronic IDP and 3 had Guillain‐Barré syndrome. In addition to an elevated cerebrospinal fluid (CSF) protein level (mean, 193 mg/dl), most patients had cerebrospinal fluid pleocytosis (mean, 23 cells/mm³), a distinctive feature. All had reduced T4:T8 T‐cell ratios. Results of nerve conduction studies were characteristic of demyelination. Nerve biopsies revealed intense inflammatory cell infiltrates and macrophage‐mediated demyelination. The patients recovered either spontaneously or following treatment with corticosteroids or plasmapheresis. During a mean interval of 20 months after presentation, only 1 patient had developed acquired immune deficiency syndrome. Patients with HTLV‐III infection have disordered immune function, and the mechanism of the development of the IDP is likely to be immunopathogenic. As a result of our experience, we suggest that all patients with IDP be tested for evidence of HTLV‐III infection. We also found, although in uncontrolled trials, that treatment with either prednisone or plasmapheresis was followed by clinical improvement; since plasmapheresis is not likely to further depress cell‐mediated immunity, we suggest that it be the initial therapy.