Neuropathy
Neuropathy
Neuropathies are disorders of peripheral nerves. Various clinical patterns of peripheral nerve involvement may be seen:
- Mononeuropathy: sensory and/or motor involvement in the distri- bution of a single nerve
- Mononeuropathy multiplex: simultaneous involvement of two or more nerves, usually in different parts of the body; if due to inflammatory disease (as is often the case) this may be described as mononeuritis multiplex
- Polyneuropathy: a widespread process, predominantly affecting the distal parts of nerves; may be predominantly sensory ("glove and stocking" sensory loss) or motor, with or without concomitant autonomic involvement.
These clinical patterns may need to be differentiated in practice from disorders affecting the neuronal cell bodies in the ventral (anterior) horns of the spinal cord or dorsal root ganglia (motor and sensory neuronopathies, respectively); and disorders of the nerve roots (radiculopathy) and plexuses (plexopathy). Clinical signs resulting from neuropathies are of lower motor neurone type (wasting, weakness, reflex diminution or loss).
The causes of neuropathy are legion. Mononeuropathies often result from local compression (entrapment neuropathy), trauma, or diabetes. Mononeuropathy multiplex often reflects intrinsic inflammation (e.g., polyarteritis nodosa, Churg-Strauss syndrome, systemic lupus erythematosus, rheumatoid arthritis, Sjögren’s syndrome, cryoglobulinemia, isolated PNS vasculitis). Polyneuropathies may have genetic, infective, inflammatory, toxic, nutritional, and endocrine etiologies. Many neuropathies, particularly polyneuropathies in the elderly, remain idiopathic or cryptogenic, despite intensive investigation.
Sensory neuronopathies (ganglionopathy, polyganglionopathy) have a rather more limited differential diagnosis, including:
- Paraneoplasia: anti-Hu antibody syndrome (although a similar syndrome, presumed paraneoplastic, may occur in the absence of these antibodies)
- Sjögren’s syndrome
- Associated with anti-GD1b ganglioside antibodies
- CIDP
- HIV.
References
Dyck PJ, Thomas PK, Griffin JW, Low PA, Podulso JF (eds.). Peripheral neuropathy (3rd edition). Philadelphia: Saunders, 1995 Feldman EL, Grisold W, Russell JW, Zifko U. Atlas of neuromuscular disease. A practical guideline. Vienna: Springer, 2005: 141-333 Kincaid JC. Neuropathy. In: Biller J (ed.). Practical neurology (2nd edition). Philadelphia: Lippincott Williams & Wilkins, 2002: 614-622 Staal A, van Gijn J, Spaans F. Mononeuropathies: examination, diag- nosis and treatment. London: WB Saunders, 1999
Stewart JD. Focal peripheral neuropathies (3rd edition). Philadelphia: Lippincott Williams & Wilkins 2000
Cross References
Amyotrophy; Lower motor neurone (LMN) syndrome; Plexopathy; Radiculopathy; Wasting; Weakness
