Your doctor will perform a thorough clinical evaluation to determine the part of the peripheral nervous system that is affected and the likely cause. The following investigations may be arranged:

Electromyography (EMG)

• This is an important investigation that will help localise and characterise the nature and severity of the peripheral neuropathy. The first part of EMG involves stimulating the peripheral nerves and recording its electrical signals. The second part involves inserting a very fine needle into the limb or back muscles and recording motor activity.

Blood investigations

• To detect an underlying cause of the neuropathy, e.g. diabetes, vitamin deficiencies and vasculitis, various blood tests may be required. In certain types of hereditary neuropathy, blood samples may be sent for genetic tests.

Lumbar Puncture

• This is a bedside procedure to withdraw a small amount of cerebrospinal fluid from the lower back under local anaesthesia. The fluid will be sent for various tests.

Skin Biopsy

• This is a simple, bedside procedure to confirm neuropathy affecting small nerve endings in the skin. Punch skin biopsies (about 3mm in diameter) are performed under local anaesthesia on the leg and thigh.

Autonomic Function Test

• This is a non-invasive test that evaluates the autonomic nervous system.

Nerve Biopsy

• This is occasionally performed to confirm the presence of nerve inflammation, e.g. in vasculitic neuropathy.