Infectious neuropathies

Infectious neuropathies are heterogeneous neuropathies with multiple causes. They still represent an important world health burden and some of them have no current available therapy.

Leprosy incidence has decreased by 50% during the last years, but leprosy-related neuropathies still cause severe disability. The pure neuritic leprosy is a diagnostic challenge that may require nerve biopsy or nerve aspiration cytology. The treatment itself may lead to a 'reversal reaction', which further causes injuries to the nerve. HCV-related neuropathies may be related or not to the presence of cryoglobulins. The absence of vasculitis, the most frequent form is a peripheral sensory neuropathy involving small nerve fibers, and more accurately diagnosed by pain-related evoked potentials. HIV-related neuropathy has become the major neurological complication of HIV infection. Both HIV-induced neuropathy and antiretroviral toxic neuropathy are clinically indistinguishable. The existence of an isolated chronic polyneuropathy due to Borrelia burgdorferi remains highly controversial. Lastly, an active infectious ganglioneuritis caused by varicella zoster virus, producing shingles, is the most frequent infectious neuropathy in the world and may cause various neurological complications. Zoster sine herpete remains frequently undiagnosed.

Recent data have improved our knowledge and diagnostic tools of infectious neuropathies. Treatment of the injured nerves is not yet available, and prevention and rapid diagnosis remain the main priorities for the clinician.