Tous les types de neuropathie périphérique peuvent compliquer l'infection par le VIH, et il semble exister une correspondance entre les neuropathies observées et l'importance du déficit immunitaire : polyradiculonévrites chez les sujets séropositifs asymptomatiques, mononeuropathies multifocales aux stades ARC et sida débutant, polyneuropathies distales à prédominance sensitive (et sourvent douloureuses) et méningoradiculites au stade de sida évolué. Les explorations électrophysiologiques sont indispensables pour préciser le type de neuropathie et l'évolution. Par ailleurs, les études électrophysiologiques systématiques chez les sujets séropositifs révèlent dans 70 à 90% des cas, y compris très précocement, des anomalies dont la signification est discutée. Les mécanismes responsables de ces altérations nerveuses périphériques sont encore largement hypothétiques.

Disorders of the peripheral nervous system occur at all stages of HIV1 infection. Acute and subacute inflammatory demyelinating polyneuropathies are mainly observed in otherwise asymptomatic HIV+ patients and in patients with ARC (AIDS-related complex): clinical and electrophysiological features are similar to those observed in Guillain-Barré syndrome (GBS) and chronic inflammatory demyelinating polyneuropathy (CIDP), but CSF examination usually shows pleocytosis, and an infiltration of the endoneurium and/or the epineurium is commonly seen in nerve biopsies. Mononeuropathy multiplex is a rare complication occurring in ARC-patients: electrophysiological studies are consistent with an axonopathy and nerve biopsies may show vasculitis. Distal predominantly sensory polyneuropathies are the most frequent peripheral neuropathies in HIV1 infection and are usually reported in patients with AIDS and severe immunosuppression: electrophysiological features are of an axonopathy with signs of acute denervation. Meningoradiculitis is observed at the late stages of the disease and is mainly due to a cytomegalovirus infection. On the other hand, systematic electrophysiological studies in HIV+ cases reveal a high percentage of abnormalities concerning sensory and less frequently motor nerve conduction velocities. The severity of this asymptomatic involvement of the peripheral nervous system seems to be related to the degree of the immunodeficiency. The mechanism of these peripheral neuropathies remains hypothetical in most cases.