Neuropathies are disorders or dysfunction of the peripheral nerves--those outside the brain and spinal cord. Hereditary diseases, trauma, toxins, infections, medications and systemic and autoimmune diseases can all cause neuropathy in which sensory and motor functions -- muscle movement and strength -- can be impaired. Pain is a common symptom whenever a sensory nerves sustains neuropathic damage.
Burning and Pinprick Sensations
Sensory neuropathies can cause burning and pinprick sensations, which generally indicate involvement of small-fiber sensory nerves. Tingling, numbness, itching and weakness may accompany these symptoms. Disorders associated with this type of neuropathic pain include diabetic neuropathy, HIV-related neuropathy, Lyme disease, sarcoidosis, shingles, systemic lupus erythematosus, niacin and thiamine deficiencies, stress injuries (such as carpal tunnel syndrome), multiple sclerosis and Guillain-Barré syndrome.
Toxins that can cause burning or pinprick neuropathic pain include alcohol in excessive amounts, lead, mercury, arsenic and organic insecticides and solvents. Notably, people who sniff glue or other chemicals for recreational purposes--commonly known as huffing--may develop peripheral neuropathy. Platinum-based chemotherapy drugs, phenytoin, amiodarone, hydralazine, nitrofuratoin, isoniazid and other medications can also occasionally cause neuropathic pain.
Whereas the burning and pinprick varieties of neuropathic pain are considered aberrant or unusual sensations, more typical pain also occurs. The nature of this pain varies and is often described as aching, dull, sharp, stabbing, throbbing, gnawing or pressing. Typical pain can occur with any of the disorders and conditions that cause aberrant neuropathic pain, however, some causes of neuropathy are more likely to elicit this type of pain than others. These include diabetes, alcoholism, toxins, shingles, sarcoidosis and systemic lupus erythematosus.
Neuropathy can result in extreme sensitivity to touch, which triggers a pain response from an experience or stimulus that does not normally cause pain. This abnormal pain response is called allodynia. In its most extreme form, this symptom makes it difficult to tolerate the movement of air, wearing clothing, bathing and a myriad of other tasks of daily living wherein the skin makes contact with the environment.
Muscular pain, also known as myalgia, may be a symptom of neuropathy. Conditions associated with neuropathic myalgia include high-dose l-tryptophan ingestion, fibromyalgia, Sjögren’s syndrome, porphyria and amyloidosis.
Some neuropathies are associated with pain limited to a specific area of the body. Trigeminal neuralgia -- also known as tic douloureux -- is a peripheral neuropathy involving the trigeminal nerve of the face. The disorder causes intense episodic pain on one side of the face--commonly in the jaw, cheek or temporal area. Spinal cord injuries also cause localized neuropathic pain; the location of the pain is usually dictated by the area of the spinal cord that was injured.