Relapsing central and peripheral demyelinating diseases. Unusual pathologic features.

We treated a patient who had a demyelinating peripheral neuropathy and a central nervous system inflammatory demyelinating disease. The unusual pathologic feature of dense infiltrates of atypical macrophages was observed in many areas of the brain; otherwise the process had several features in common with either multiple sclerosis or chronic relapsing experimental allergic encephalomyelitis. The illness followed "swine-flu" inoculation; exacerbation followed pneumococcal vaccination.