Hereditary Neuropathy

Hereditary neuropathies are a group of inherited disorders affecting the peripheral nervous system. They are divided into four major subcategories:

• Hereditary motor and sensory neuropathy
• Hereditary sensory neuropathy
• Hereditary motor neuropathy
• Hereditary sensory and autonomic neuropathy

The most common type is Charcot-Marie-Tooth disease (CMT), one of the hereditary motor and sensory neuropathies.

Presenting symptoms

• Muscle weakness, particularly in the lower leg and feet muscles, and sometimes the hand muscles
• Foot deformities such as high arches and hammer toes
• Loss of muscle bulk, for example, thin calf muscles (having the appearance of an inverted champagne glass) or thin hand muscles
• Scoliosis (curvature of the spine)
• Numbness
• Tingling
• Pain in the feet and hands
• Insensitivity to pain
• Impaired sweating
• Postural hypotension ( a drop in blood pressure due to a change in body position when a person moves to a more vertical position)

Onset of symptoms of hereditary neuropathies may be apparent at birth or appear in middle or late life. They can vary among different family members, with some family members being more severely affected than others. Some hereditary neuropathies have very mild symptoms and may go undiagnosed for many years. Other types are more severe and are associated with more disabilities.

Diagnosis

The hereditary neuropathies can be diagnosed by nerve conduction studies and blood tests for genetic study. Rarely, nerve biopsies may be needed.