Peripheral neuropathy is a condition in which the most distal (peripheral nerves) are injured or damaged. This usually manifests in the feet first but can affect the hands if it progresses. Symptoms are often described as burning, stabbing, or tingling pain but also include numbness and weakness in a stocking and glove distribution. It can also affect sensory perception, including temperature, pain, and vibration. The onset of symptoms is typically gradual, often over months or years.
Many diseases or conditions can contribute to the development of peripheral neuropathy. The most common cause is diabetes, while other somewhat frequent contributors are vitamin B-12 deficiency, hypothyroidism, and alcohol use. There are several much less common causes, including autoimmune diseases, infections, inherited disorders, medications, chemotherapy, and heavy metal exposure. Age is also a contributing factor. About half of the cases in the United States are idiopathic (have no identifiable causative source).
There is recent research that about half of idiopathic cases may be due to a delayed return-to-normal fasting blood sugar after a meal even though such an individual may have normal fasting blood sugar and normal a hemoglobin A1C. The implication is that not only is having chronically high levels of blood sugar damaging to nerves but so can intermittently prolonged elevated blood sugars.
There is also new data showing there is a relationship with the fluoroquinolone family of antibiotics (Cipro, Levaquin, etc.) and the development of peripheral neuropathy. This has only been found with oral, IV, or injectable administration. It is not known if there is an association with eye or ear drops causing neuropathy. It is unknown if these side effects are permanent or temporary, but one British study found symptoms that developed after fluoroquinolone antibiotics lasted up to 180 days after exposure
If peripheral neuropathy is suspected by history or examination, it can sometimes be detected by nerve function tests (EMG). Other causes of nerve symptoms, such as being referred from the spine, need to be ruled out. Blood tests can be ordered to assess for identifiable causes such as hypothyroidism and Vitamin B12 deficiency. The primary treatment is focused on correcting any identifiable causative factors such as better management and control of hypothyroidism or diabetes. For patients where it is idiopathic, dietary changes could still help. Decreasing alcohol intake and low sugar diets could both prove to be beneficial. From a medication standpoint, anti-seizure medications such as gabapentin or Lyrica can be helpful. Some antidepressant-type drugs such as Cymbalta can also control the symptoms. Physical therapy can be helpful for the treatment of weakness and balance changes associated with neuropathy.
If you have additional questions or want to discuss the diagnosis or treatment options in further detail, please feel free to make an appointment with a provider at Spine West.
Written by Vaheed Sevvom, PA-C