[A case with posterior column ataxia associated with cerebellar ataxia and sensory neuropathy]

The patient was a 72-year-old man who had a history of subtotal gastrectomy for gastric ulcer at age of 37 years. He had no familial history of hereditary disorders. In 1980 he noticed mild ataxic gait which exaggerated while he closed eyes. The symptoms increased gradually, and four years later he noticed hypoesthesia of his soles. In 1983 he was admitted to the National Center Hospital for Mental, Nervous and Muscular Disorders for the first time. Neurological examination revealed dysarthria, ataxic gait, disturbance of coordination to a slight degree, and muscle strength of the upper and lower limbs were in normal range. Mild hypoesthesia of pain and temperature sensation, and marked decrease of deep sensation and vibration of the lower extremities were demonstrated. Romberg sign was positive. EMG studies revealed low amplitude of action potential and normal motor nerve conduction velocity. Biopsy of the sural nerve showed marked decrease of both large and small myelinated fibers. In 1998 he was admitted second time for the further examination. Laboratory examination including routine blood examination, blood chemistry including CRP, TPHA, vitamin B1, B2, B12, A, E, K, hexosaminidase A in leucocyte were in normal range. CSF was normal. Genetic studies including SCA 1, 2, 3, 6, DRPLA, CMT1A, CMTX 1 were all negative. MCV of lower limbs was in normal range, though SCV was not evoked in the upper and lower limbs. MRI studies showed mild atrophy of the bilateral lobulus of the cerebellum which was not so much changed in the last 5 years. The clinical symptoms revealed dominant posterior column disturbance, ataxia and sensory neuropathy. These combination was not described in the previous literature, and this case may be a new variant of the spinocerebellar degeneration.