Pure sensory neuropathies are clinically characterized by paresthesias, sensory ataxia and areflexia without muscle weakness. We report the case of a 21 years-old female patient with acute onset of distal paresthesias, marked sensory ataxia and hyporeflexia. Motor strength was normal. Sensory nerve conduction was absent and motor nerve conduction slightly decreased. CSF showed 2 leucocytes/mm3 and 1.06 g/dL protein. Collagen disorder and neoplasia were not found. Type 2 fiber atrophy was observed on muscle biopsy, and axonal demyelination on sural nerve biopsy. The patient was treated with prednisone. After 1.5 years she was recovered, but a minor proprioceptive deficit persisted. A revision is made on the etiology, pathophysiology and clinical manifestations of the disease.