Familial amyloid neuropathy

Familial amyloid neuropathy (FAN), also known as Familial amyloid polyneuropathy (FAP), is a rare genetic disorder characterized by the production of abnormal protein deposits, known as amyloid, in various tissues and organs of the body. These deposits can lead to a wide range of symptoms, depending on the organs affected.

Etiology

FAN is caused by mutations in the Transthyretin (TTR) gene. This gene provides instructions for making a protein that carries thyroid hormones in the blood and cerebrospinal fluid. Mutations in the TTR gene cause the protein to misfold, leading to the formation of amyloid deposits.

Symptoms

The symptoms of FAN can vary widely, depending on the organs affected by the amyloid deposits. Common symptoms include peripheral neuropathy, autonomic neuropathy, and cardiomyopathy. Other symptoms can include gastrointestinal disturbances, renal dysfunction, and ophthalmological problems.

Diagnosis

Diagnosis of FAN is based on a combination of clinical symptoms, family history, and genetic testing. Biopsies of affected tissues can also be used to confirm the presence of amyloid deposits.

Treatment

Treatment for FAN is aimed at managing symptoms and slowing the progression of the disease. This can include medications to manage neuropathic pain and gastrointestinal symptoms, as well as interventions to manage cardiac and renal complications. In some cases, liver transplantation or stem cell transplantation may be considered.

Prognosis

The prognosis for individuals with FAN can vary widely, depending on the specific mutation in the TTR gene, the organs affected, and the individual's overall health. With appropriate management, many individuals with FAN can lead productive lives.

See also

• Amyloidosis
• Transthyretin-related hereditary amyloidosis
• Genetic disorder
• Neuropathy