Antibody-negative neuromyelitis optica with heavy B-cell infiltration.

There are several distinct clinical phenotypes of inflammatory demyelinating diseases of the central nervous system. In classical multiple sclerosis (MS) there are varied pathological patterns, possibly with differences in pathogenesis. Neuromyelitis optica (NMO) is often associated with a specific antibody, suggesting a distinct pathogenesis. We report a case of a young Caucasian male who presented with right hemiparesis secondary to a left fronto-parietal inflammatory brain lesion, which improved over years leaving minimal deficit. Seventeen years later he re-presented with a progressive tetraparesis secondary to cervical myelitis that did not respond to treatment. The NMO antibody was not detected and neuropathological examination was unusual with evidence of a persistent B-cell inflammatory response in the cord. Although having some of the clinical features of NMO, this case presented novel clinico-pathological features that do not easily fit into current MS subtypes.