Which are the symptoms?
Onset usually occurs in adulthood. Symptoms include weakness, numbness, pain and tingling in the upper limbs, but lower limbs may also be affected; usually asymmetrical. The trend is slowly progressive or with "stepwise" worsening. During the visit, the doctor may detect a deficit in strength, impaired sensitivity, or lack of reflexes in the affected areas.
How is it diagnosed?
For diagnosis, it is important to perform electromyography, which will show typical results (in particular, blockade of conduction of both motor and sensory nerves in several atypical places due to entrapment). Additional tests that can help diagnose are lumbar puncture and MRI of the brachial plexus.
How is it treated?
The most commonly used treatment for Lewis-Sumner syndrome is intravenous immunoglobulin (IVIg). This type of therapy is successful in about 80% of cases. However, in a significant number of cases, stabilization occurs without treatment.