This report describes a 26 year old woman with a Coxsackie B virus infection complicated by an acute pandysautonomic and sensory neuropathy. Electrophysiological studies suggested an axonal neuropathy. A sural nerve biopsy performed early in the disease showed axonal degeneration with a virtual absence of unmyelinated fibres and moderate loss of myelinated fibres, mainly affecting the small fibres; this differs from previous reports. An immune-mediated or direct virus action might explain the pathogenesis of this unusual evolution of a viral infection.