Inherited Neuropathy — Can Numbness Be Hereditary?

Inherited Neuropathy

Eye color, shoe size, and height all have one thing in common — they’re hereditary. It turns out inherited neuropathy can be, too.

While it’s rare, children who have a parent with heritable neuropathy have a 50 percent chance of developing the condition, as well. It can show up as early as birth, but it’s more frequently diagnosed in middle- and older-age. Type 2 diabetes and obesity are also risk factors.

According to an Annals of Indian Academy of Neurology study, there are more than 30 genes that are linked to inherited neuropathy. A neurologist can diagnose whether you have the condition via nerve conduction studies, nerve biopsies, or genetic testing.

There are two common forms of inherited neuropathies — Charcot-Marie-Tooth (CMT) and Hereditary Neuropathy with Liability to Pressure Palsies (HNPP). Overall, they share many similar symptoms. Individuals experience pain and tingling in their hands and feet, muscle weakness and loss of mass in their feet and lower legs.  They also experience impaired sweating, low blood pressure upon standing up, and physical deformities, such as high foot arches, hammertoes, and curved spine.

What Happens With CMT?

CMT affects approximately 1 in 3,300 people. There are many CMT subtypes, but CMT1A is the most common. It affects 20 percent of people who seek medical attention for undiagnosed peripheral neuropathy.

Patients with CMT have difficulty lifting their feet, weak ankles, drop foot, and have unsteady balance. They also exhibit poor hand coordination, making it harder to hold pencils, button or zip clothes, and turn door knobs. Additionally, they can be hyper-sensitive to cold temperatures. Muscle weakness and poor circulation can turn hands and feet cold, as well as lead to ankle and foot swelling.

Sometimes, individuals with CMT can also lose their knee-jerk reactions and experience hand tremors. This is called Roussy-Levy Syndrome. Additionally, weak breathing and shortness of breath are rare, but they can be life-threatening. If those symptoms appear, a respiratory specialist might recommend a ventilator.

What Occurs With HNPP?

HNPP is even more rare than CMT, appearing in 2-5 individuals per 100,000.

Affected individuals are extremely sensitive to pressure, and they can have difficulty carrying heavy bags, leaning on their elbows, or sitting in chairs. Frequently, they experience tingling, numbness, and loss of sensation in areas impacted by the neuropathy. These symptoms typically strike the hands, arms, feet, and legs.

Often, HNPP episodes last for several months. Long durations can lead to permanent muscle weakness and sensation loss.

Prevention & Treatment

There’s no way to prevent inherited neuropathy, but genetic counseling is available to parents who worry about passing the condition on to their children.

Additionally, there’s no cure, but ongoing management techniques can greatly improve quality of life. For example, pain medications, physical therapy, corrective surgery, therapeutic shoes, braces, and support devices can greatly reduce the impact inherited neuropathy has. A balanced diet and exercise are also beneficial.

Be sure to seek medical attention as soon as symptoms for inherited neuropathy appear. The earlier the diagnosis, the better prognosis and outlook you’ll have.

For more information, contact the Amputation Prevention Centers of America.