Polyneuropathies

Polyneuropathies are functional disorders of the peripheral nerves in the context of a generalized or systemic disease.

There is a predominantly symmetrical distribution of symptoms and findings, distal- and leg-stressed. Depending on the cause, there is a slow to rapid progression.
Sensitivity disorders may be present in "sock- and glove-shaped" distribution, also paresthesia and possibly burning pain. In addition, there is an early loss of vibration sensation.

Motor failures usually begin with weakness in foot dorsiflexion. A muscular atrophy is initially observed in the small foot and hand muscles, and in the further course of time the lower legs and forearms are also affected. This leads to an early failure of the Achilles tendon reflex.

Trophic disorders are observed on the skin and nails, for example. Vegetative disturbances on the other hand on sweat secretion as well as disturbances of sexual, bladder and rectum function and orthostatic hypotension.

For the diagnosis of polyneuropathies, in addition to a medical history, clinical examinations and neurological consiliary tests must be performed.

Laboratory: Basic program with BSG, blood count, TSH-basal, transaminases, creatinine, electrolytes, CK, serum electrophoresis (an IgM-associated polyneuropathy is the most common paraproteinemia associated with polyneuropathy; formation of anti-MAG antibodies directed against a glycoprotein in the myelin sheaths of peripheral nerves), vitamin B12 and folic acid levels.

CSF diagnostics and lumbar puncture

Special neurological diagnostics: for example electrokyography, electroneurography, somatosensory and motor evoked potentials.

Nerve/muscle biopsy (in unclear cases)

Muleular genetic investigations to clarify a hereditary polyneuropathy.

Symptomatically, neuralgiform (polyneuropathic) pain can be treated with carbamazepine, gabapentin or pregabalin. Burning pain is treated with amitriptyline, duloxetine, and for cramp-like pain with alternating foot baths quinine sulphate. Other types of pain that are resistant to therapy: Clomipramine or Amitriptyline.