Vitamin deficiencies are rarely a result of isolated deficit of one vitamin alone. B1 - Diet high in calories, but deficient in vegetables. Distal, motor poly neuropathy due to axonal degeneration. B12 - Pernicious anemia produces a myelopathy and axonal degeneration involving mainly large fibers. Folate Deficiency of folate is thought to be responsible for the distal polyneuropathy in chronic anti-convulsant therapy.
Axonal transport is affected.
Organophosphate compounds may produce fasciculations. Drugs, in particular Isoniazide and ethambutol used to treat TB, vincristine used in cancer chemotherapy and some antibiotics, can produce significant neuropathies. Cancer Factors producing neuropathies in cancer patients include nutritional deficiency, chemotherapeutic agents and concurrent metabolic disorders. Myeloma and macroglobulinemia are accompanied by neuropathy. The most common picture is of a distal sensori-motor polyneuropathy sometimes preceding diagnosis of the Ca.