Tangier disease was so named because it was originally described among residents living on Tangier Island located in the Chesapeake Bay. The first settlers to this island arrived in 1686 and many descendents are said to still speak with a unique Elizabethan dialect. Since the first report in 1961, this rare disorder has been found in other states as well as other areas of the world.
This is a disorder of fat (lipid) metabolism that leads to deposits of fats in various tissues of the body including the cornea and the conjunctiva. This can lead to some vision loss, especially in older individuals (the deposits are progressive). Of more serious concern are the deposits in other organs such as the liver, spleen, tonsils, blood vessels, and lymph glands. There is a significant risk of coronary artery disease which may lead to heart attacks, even among individuals in their 40s and 50s. Peripheral nerves such as those in the arms and legs may be affected with loss of sensation and muscle weakness with muscle atrophy.
Some patients with Tangier disease, in addition to the clouding of the cornea may have difficulty blinking and closing their eyes properly leading to drying out of the cornea and additional vision problems.
This is an autosomal recessive disorder resulting from a mutation in a gene necessary to metabolize dietary fats properly. To inherit Tangier disease, one has to have two copies of a mutation, one from each (carrier) parent who does not have the disease since they have only a single mutation. Such parents can expect that each child has a 25% risk of inheriting both mutations from them and therefore of having Tangier disease.
A determination of the lipids carried in the blood is necessary to diagnose this disorder but presence of the disease is suggested by the combination of corneal cloudiness with the characteristic enlargement of the liver, lymph glands, spleen and tonsils. Patients should be monitored for coronary artery involvement by a cardiologist who can suggest appropriate intervention for heart disease. There is a wide range of symptoms and signs with prognosis dependent upon the severity of disease.
It is important for patients to be followed by an ophthalmologist for treatment of dry eyes as lack of moisture can lead to serious corneal disease and loss of vision.