Neuritis

Neuritis (/njʊəˈraɪtɪs/), from the Greek νεῦρον),^[1] is inflammation of a nerve^[2] or the general inflammation of the peripheral nervous system. Inflammation, and frequently concomitant demyelination,^[3][4][5] cause impaired transmission of neural signals and leads to aberrant nerve function. Neuritis is often conflated with neuropathy, a broad term describing any disease process which affects the peripheral nervous system. However, neuropathies may be due to either inflammatory^[6] or non-inflammatory causes,^[7] and the term encompasses any form of damage, degeneration, or dysfunction, while neuritis refers specifically to the inflammatory process.

As inflammation is a common reaction to biological insult, many conditions may present with features of neuritis. Common causes include autoimmune diseases, such as multiple sclerosis; infection, either bacterial, such as leprosy, or viral, such as varicella zoster; post-infectious immune reactions, such as Guillain-Barré syndrome; or a response to physical injury, as frequently seen in sciatica.^[8][9]

While any nerve in the body may undergo inflammation,^[10] specific etiologies may preferentially affect specific nerves.^[11] The nature of symptoms depends on the specific nerves involved, neuritis in a sensory nerve may cause pain, paresthesia (pins-and-needles), hypoesthesia (numbness), and anesthesia, and neuritis in a motor nerve may cause paresis (weakness), fasiculation, paralysis, or muscle wasting.

Treatment of neuritis centers around removing or managing any inciting cause of inflammation, followed by supportive care and anti-inflammatory or immune modulatory treatments as well as symptomatic management.