[Peripheral neuropathies]

Some new aspects of peripheral nerve disease are reviewed. Hereditary motor and sensory neuropathy (HSMN) constitutes a genetically heterogeneous group of chronic polyneuropathies with loci mapping to chromosome 17 (type Ia), chromosome 1 (type Ib), and the X chromosome (X-linked HSMN). Although peripheral nerve abnormalities occur in approximately 50% of diabetic patients, the frequency of severe diabetic neuropathy even in insulin-dependent persons is rather modest (6%). Intensified insulin treatment seems more important for preserving peripheral nerve function than treatment with aldose reductase inhibitors. Acute inflammatory demyelinating polyradiculoneuropathy (Guillain-Barré syndrome) and chronic inflammatory demyelinating polyneuropathy may both be beneficially influenced by plasma exchange or intravenous immunoglobulin. In acute inflammatory demyelinating polyradiculoneuropathy, campylobacter jejuni infection is a common preceding event. There is some evidence of cross reactivity between this infectious agent and the ganglioside GM1 in peripheral nerve myelin.