HIV infection and the PNS

Peripheral nervous system involvement is one of the most common neurological complications of HIV infection. Although type of peripheral nervous system involvement varies depending on the stage of infection, most prevalent type of involvement is HIV-associated distal sensory polyneuropathy. Mechanisms of HIV-associated peripheral neuropathies are unknown. HIV is neuroinvasive and neurovirulent, but not necessarily neurotrophic, suggesting that most of the neurotoxicity of HIV infection is indirect and most likely mediated via chemokines, cytokines, or viral proteins released by the infiltrating macrophages. Furthermore, treatment with antiretroviral drugs contributes to neurotoxicity and development of peripheral neuropathies, sometimes clinically indistinguishable from HIV-induced peripheral neuropathy. Mechanism of antiretroviral toxic neuropathy is likely to be mediated by mitochondrial toxicity leading to distal axonal degeneration. Currently, treatment of HIV-associated peripheral neuropathies is directed at symptom control and strict control of the underlying HIV infection without the use of most toxic antiretroviral drugs.