Neuritis, also known as peripheral neuropathy, is any disorder of the peripheral nervous system which interferes with sensation, the nerve control of muscle, or both.

 

Causes or neuritis include drugs and heavy metals (e.g., gold); infection or allergic reaction to it (as with leprosy or diphtheria); inflammatory disease (rheumatoid arthritis); infiltration, systemic, and metabolic disease (e.g., diabetes or porphyria); vitamin deficiency (beriberi); organ failure (e.g. of the liver or kidney); genetic disorders, and the nonmetastatic effects of distant cancer.

 

Numbness, tingling, weakness, and paralysis result, at first affecting the extremities. Diagnosis involves electrical studies of the nerves and nerve biopsy.