Diagnosis
The diagnosis of polyneuropathies begins with a history and
physical examination to ascertain the pattern of the disease process (such as-arms, legs, distal, proximal) if they fluctuate, and what deficits and pain are involved. If pain is a factor, determining where and how long the pain has been present is important, one also needs to know what disorders are present within the family and what diseases the person may have. Although diseases often are suggested by the physical examination and history alone, tests that may be employed include: electrodiagnostic testing, serum protein
electrophoresis,
nerve conduction studies,
urinalysis, serum
creatine kinase (CK) and
antibody testing (nerve biopsy is sometimes done).
Other tests may be used, especially tests for specific disorders associated with polyneuropathies, quality measures have been developed to diagnose patients with distal symmetrical polyneuropathy (DSP).
In terms of the differential diagnosis for polyneuropathy one must look at the following:
Classification
Polyneuropathies may be classified in different ways, such as by
cause,
[1] by
presentation,
[3] or by
classes of polyneuropathy, in terms of which part of the nerve cell is affected mainly: the
axon, the
myelin sheath, or the
cell body.
[7][8]
- Distal axonopathy, is the result of interrupted function of the peripheral nerves.[9] It is the most common response of neurons to metabolic or toxic disturbances, and may be caused by metabolic diseases such as diabetes, kidney failure, connective tissue disease, deficiency syndromes such as malnutrition and alcoholism, or the effects of toxins or drugs such as chemotherapy. They may be divided according to the type of axon affected (large-fiber, small-fiber, or both), the most distal portions of axons are usually the first to degenerate, and axonal atrophy advances slowly toward the nerve's cell body, however if the cause is removed, regeneration is possible, although the prognosis depends on the duration and severity of the stimulus[medical citation needed]. People with distal axonopathies usually present with sensorimotor disturbances such as amyotrophic lateral sclerosis[10]
- Myelinopathy, is due to a loss of myelin or of the Schwann cells.[11] This demyelination slows down or completely blocks the conduction of action potentials through the axon of the nerve cell(neurapraxia).[12] The most common cause is acute inflammatory demyelinating polyneuropathy AIDP, the most common form of Guillain–Barré syndrome[13](although other causes include chronic inflammatory demyelinating polyneuropathy )[14]
- Neuronopathy is the result of issues in the peripheral nervous system (PNS) neurons. They may be caused by motor neurone diseases, sensory neuronopathies, toxins, or autonomic dysfunction. Neurotoxins such as chemotherapy agents may cause neuronopathies.[15]
https://en.wikipedia.org/wiki/Polyneuropathy
