Neuropathy is formed by the combination of the words "Neuron" (nerves) and "Pathos" (disease). So by definition, it is simply the disease of nerves.
Neuropathy defines any type of disease that affects the nerves in the body. It is a broad term that defines injuries or diseases to many of the nerves in the body and there are various forms of neuropathy. This group of diseases is characterized by impaired nerve function which causes a problem with sensation, function and movement of the areas affected.
Neuropathy could be:
The cause of neuropathy can either be acute or chronic and they include diabetes, which is the commonest cause. Others are chronic alcoholism, vitamin B12 deficiency, autoimmune diseases, renal failure, hepatic failure, inherited disorders, toxins, infections, drugs, trauma and tumors. It could also be idiopathic, meaning that there could be no known cause.
The incidence and prevalence, along with the distribution amongst sex, race and age is largely dependent on the type of neuropathy.
Neuropathy due to trauma is more likely to occur in the mid-life as this is when individuals are more prone to accidents. The incidence is predominantly higher in males as they are more at risks of trauma from falls or assault.
Neuropathies of hereditary origin usually start in childhood but may remain unnoticed until later in life. They have no clear age, sex or race predilection.
The pathophysiology of neuropathy is largely dependent on the underlying cause.
In diabetes mellitus, there have been different postulated theories about the pathway that leads to nerve damage. It is however agreed that many factors interplay in its pathophysiology, like the reaction of excess glucose with certain cellular bodies that leads to production of glycation end product which affects nerve function. Also, the accumulation of sorbitol and fructose from the metabolism of excess glucose in the polyol pathway can lead to nerve damage. Also, the increased production of free radicals in patients with diabetes has been implicated in its pathophysiology.
In neuropathy due to trauma, the major mechanism is shearing of nerves either by accidents or during surgeries to remedy other conditions like a brachial plexus injury following surgery on the axilla. The development is usually sudden
In other forms like Vitamin B12 deficiency and the inherited types, the major end result appears to be demyelination of nerves although the clear pathway by which this occurs is not clearly understood.
The prognosis depends on the type of neuropathy. However, if diagnosis is made early and treatment instituted, then the progression of the disease can be slowed or even reversed thereby giving the patient a better prognosis.
Symptoms of neuropathy depends on the nerves affected.
Other investigations that may be carried out are electromyography, nerve conduction tests, nerve biopsy, electrocardiogram, and microdialysis.
The treatment of neuropathy usually targets the underlying cause. For example, vitamin supplements in Vitamin B12 and folate deficiency. Also, if diabetes is diagnosed and managed early, the risk for developing peripheral neuropathy is greatly reduced.
Pain management is also very important and because patients with neuropathy do not readily respond to regular analgesics, medication that target specific nerve cells are preferred. Drugs such as duloxetine hydrochloride is used. Other drugs include some anticonvulsants, antiarrhythmics, and local anesthetics. Topical analgesics can also be used in patients with focal neuropathy.
Physical therapy like massage also has a role in alleviating the pain of neuropathy. Surgery also has a role in the management of neuropathy. For example patients who have developed a gangrenous foot from a diabetic foot ulcer secondary to neuropathy may require amputation.
The mainstay of prevention is to prevent the root cause of neuropathy. Patients with diabetes should ensure adequate glycemic control. Also, a healthy diet prevents vitamin deficiency.
Neuropathy is a condition that refers to various diseases that affects the nerves of the body.
It is caused by a number of factors like diabetes, vitamin deficiency, infections and inherited disorders. Other causes include injuries, kidney disease, liver disease, drugs, poisons and long term use of alcohol.
Signs and symptoms
Common symptoms of neuropathy are pain, feeling of numbness, tingling sensation also known as ‘pins and needles’ sensation and in some cases, ulcers might develop like in diabetes. Other symptoms are erectile dysfunction, increased heart rate, constipation, nausea, vomiting, blurred vision, blindness and deafness depending on the nerves affected.
Diagnosis involves a lot of laboratory tests to check the level of sugar and vitamins, to ascertain the kidney and liver function, to know the blood level and to screen for cancers. Some other tests will also be done to check the electrical activity of nerves and the blood supply to affected areas
Treatment involves managing the cause of the neuropathy. It also involves reducing the pain felt by patients via a number of methods. In some patients, surgery might be indicated.