[Sensory ataxic neuropathy presenting anti-a-fodrin antibody associated with rheumatoid arthritis]

We reported a 41-year-old woman with severe rheumatoid arthritis who developed chronic sensory ataxic neuropathy and anti-a-fodrin antibody. Neurological examinations, electrophysiological studies and sural nerve biopsy findings suggested dorsal root ganglioneuronopathy. T2*-weighted MRIs showed high signal intensities in the posterior column of the cervical and thoracic spinal cord, suggesting the degeneration of the posterior column of the spinal cord caused by ganglioneuronopathy. She showed xerophthalmia but no other manifestations indicating Sjögren's syndrome including sialography and salivary gland biopsy findings. In serological studies, although anti-SS-A/SS-B antibodies and anti-ganglioside antibodies were negative, her serum reacted to a-fodrin, a 120kD protein degraded from a chain of fodrin. As a-fodrin has been recently regarded as an autoantigen highly specific to Sjögren's syndrome and its antibody is likely to appear preclinically, she may develop Sjögren's syndrome in the future. It is essential to accumulate clinical and pathological findings of cases like ours in order to elucidate an etiological relationship between anti-a-fodrin antibody and dorsal root ganglioneuronopathy.