What is Familial Amyloid Polyneuropathy?

MIAMI - April 16, 2019 - PRLog -- Familial Amyloid Polyneuropathy (FAP) is an inherited disease that causes progressive sensorimotor and autonomic nerve disorder. Peripheral nerve degeneration (polyneuropathy) begins in small fibers, resulting in sensory symptoms of numbness, burning, and tingling — typically in the feet. This progresses to larger nerve fibers, which leads to muscle weakness and motor impairment throughout the body.

Gastrointestinal disturbances are a common autonomic manifestation — irritability, malabsorption, and eventual wasting. Death may occur within a decade of symptom onset.

Unexplained carpal tunnel syndrome is often an early feature, due to the involvement of nerves in the wrists. The disorder also involves the heart.

Because of the associated gastrointestinal, wrist, and cardiac involvement patients may visit numerous specialists, yet the underlying diagnosis is often missed.

Familial Amyloid Polyneuropathy is caused by an inherited defect in the liver's synthesis of transthyretin (TTR), a protein which normally transports thyroxin hormone and Vitamin A in the bloodstream. There is a genetic glitch in the formation of transthyretin, which misshapes the protein. This creates a toxic residue on peripheral nerves, as well as, the heart and liver. Many patients eventually undergo a heart and liver transplant.

A new medication was approved in late 2018 specifically targeting the creation of toxic transthyretin.

The neurologic evaluation of FAP includes obtaining a family history, a physical exam to identify carpal tunnel syndrome or other clinical signs of neuropathy, a nerve test, and a confirmatory genetic screening using a small sample of saliva. This is all easily conducted in the doctor's office.

If your work-up is positive, treatment begins with the new medication, which is given via injection. This results in a dramatic decrease in circulating transthyretin, reduction of neuropathic symptoms, and improvement of the quality of life.

A potentially life-threatening neurologic disease is now easily diagnosed and effectively treated. Family members can be genetically screened and addressed early-on.

To learn more about Familial Amyloid Polyneuropathy, visit https://www.fcneurology.net/familial-amyloid-polyneuropathy/