[Histopathological features of chronic inflammatory demyelinating polyradiculoneuropathy]

Chronic inflammatory demyelinating polyneuropathy (CIDP) was proposed by Dyck et al. in 1975. Diagnosis was based mainly on nerve biopsy features with segmental demyelination, onion bulb formation and inflammatory infiltrates. In many pathological studies, frequencies of these features of CIDP were not observed in the same percentages. Limitations on the nerve biopsy were explained by the study of small, distal, only sensory nerve specimens in the lower limb. In recent years, the usefulness of nerve biopsy has been reconsidered. If electron microscopy and teased-fiber studies are used, the examination can recognize CIDP erroneously classified as chronic idiopathic axonal polyneuropathy. Therapeutic options should be guided by suggestive abnormalities of demyelination and or inflammation on nerve biopsy even in the presence of a electrophysiologic axonal pattern.