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Coats disease


Other Names for this Disease

  • Retinal telangiectasis
See Disclaimer regarding information on this site. Some links on this page may take you to organizations outside of the National Institutes of Health.

Overview

What is Coats disease?

What are the signs and symptoms of Coats disease?

What causes Coats disease?

How is Coats disease inherited?

Is genetic testing available for Coats disease?

How is Coats disease diagnosed?

How might Coats disease be treated?

What is the long-term outlook for people with Coats disease?

What is Coats disease?

Coats disease is an eye disorder characterized by abnormal development of the blood vessels in the retina (retinal telangiectasia). Most affected people begin showing symptoms of the condition in childhood. Early signs and symptoms vary but may include vision loss, crossed eyes (strabismus), and a white mass in the pupil behind the lens of the eye (leukocoria). Overtime, coats disease may also lead to retinal detachment, glaucoma, and clouding of the lens of the eye (cataracts) as the disease progresses. In most cases, only one eye is affected (unilateral). The exact underlying cause is not known but some cases may be due to somatic mutations in the NDP gene. Treatment depends on the symptoms present and may include cryotherapy, laser therapy, and/or surgery.[1][2]
Last updated: 12/15/2014

What are the signs and symptoms of Coats disease?

The signs and symptoms of Coats disease typically begin at an early age (between ages 6 and 8).[2] Some people may only have a few or no symptoms, while others are very severely affected.[1] The condition is almost always progressive (symptoms get worse over time), although alternating periods of sudden worsening with periods of no apparent progression are common.[2]

Early signs and symptoms may include loss of vision, crossed eyes (strabismus), and/or the development of a white mass in the pupil behind the lens of the eye (leukocoria).[1] As the disease progresses, affected people may develop glaucoma; cataracts; reddish discoloration in the iris (rubeosis iridis or neovascular glaucoma); shrinking of the affected eyeball (phthisis bulbi); and/or swelling and irritation of the middle layer of the eye (uveitis). The majority of affected people eventually experience profound vision loss and retinal detachment.[1][2]
Last updated: 12/15/2014

What causes Coats disease?

The exact cause of Coats disease is not currently known. However, it is a reported feature of several different genetic syndromes, suggesting there may be a genetic component.[3] Researchers believe that some cases of Coats disease may be due to somatic mutations in the NDP gene, which lead to deficient levels of a protein called norrin in the developing retina.[4] A somatic mutation in this case is one that is acquired after conception (i.e. it was not inherited from a parent and cannot be passed on to an affected person's children).
Last updated: 12/15/2014

How is Coats disease inherited?

In most cases, Coats disease is not inherited.[1] Eighty to 90% of affected people have no evidence of a genetic predisposition to the condition and no affected family members.[2]

Rarely, Coats disease can be inherited as a feature of several different genetic syndromes. For example, Coats disease has been reported in people with Senior-Loken syndrome and is a key symptom of a condition called Coats plus syndrome, which is characterized by Coats disease plus abnormalities of the brain, bones, gastrointestinal system, and other parts of the body. Both of these conditions are inherited in an autosomal recessive manner.[2][5][6]

Last updated: 12/15/2014

Is genetic testing available for Coats disease?

Genetic testing is not available for most cases of Coats disease. Eighty to 90% of affected people have no evidence of a genetic predisposition to the condition and no affected family members.[2]

Rarely, Coats disease can be inherited as a feature of several different genetic syndromes. For example, Coats disease has been reported in Senior-Loken syndrome, which is caused by changes (mutations) in one of several different genes, and Coats plus syndrome, which is caused by mutations in CTC1.[5][6][2] Genetic testing is often an option for people affected by one of these conditions.
Last updated: 12/15/2014

How is Coats disease diagnosed?

A diagnosis of Coats disease is often suspected based on the presense of characteristic signs and symptoms on thorough eye examination. Retinal fluorescein angiography, an imaging technique that uses a special dye and camera to look at blood flow in the retina, may be necessary to confirm the diagnosis. Ultrasonography, computed tomography (CT scan) and/or magnetic resonance imaging (MRI scan) are often performed to distinguish Coats disease from other conditions that affect the retina.[2][1]
Last updated: 12/15/2014

How might Coats disease be treated?

The treatment of Coats disease depends on the signs and symptoms present in each person.[1] Treatment is usually directed towards destroying affected blood vessels in the retina and salvaging as much vision as possible.[3] A procedure that uses extreme cold to destroy abnormal blood vessels (cryotherapy), and/or a procedure that uses laser energy to heat and destroy abnormal tissue (photocoagulation) are often used singly or in combination.[1] These procedures are typically used during the early stages of the disease along with steroids and other medications to control inflammation and leaking from blood vessels.[3][1]

More advanced cases may require surgical treatment.[3] For example, surgery to reattach the retina may be necessary in cases of retinal detachment.[1] Draining or surgically removing the fluids that fill the eyeball between the lens and the retina (vitrectomy) may also be used to treat Coats disease when retinal detachment is present.[3]
Last updated: 12/15/2014

What is the long-term outlook for people with Coats disease?

Factors that effect the long-term outlook (prognosis) for people with Coats disease include the stage at which the person is diagnosed, the rate of disease progression, and the effectiveness of treatment. An ophthalmologist (doctor who specializes in eye problems) with experience in the condition may be able to make a general prediction about the chances of retaining the eye and preserving vision. It has been reported that most people respond well to treatment, but approximately 25% will become worse or require removal of the eye. The visual outcome in affected people varies considerably.[7]

When Coats disease is first diagnosed in older children and young adults, it tends to be less aggressive. In some older children and young adults, spontaneous regression (improvement of symptoms) has been reported. If macular exudation (escape of fluid, cells, and cellular debris from blood vessels) and extensive retinal detachment (such as in stages 1 and 2A) are not present at diagnosis, a good visual outcome can be expected. However, the presence of thick foveal (a small area in the retina responsible for the acute vision) exudation (stage 2B disease and above) is usually associated with a worse prognosis. Most experts agree that visual prognosis is poor in people with total retinal detachment (stage 3B and above), which is usually characterized by little to no useful vision in the affected eye despite treatment. Younger children typically have more aggressive disease and often have a total retinal detachment by the time they are diagnosed; these children usually have a poor visual outcome.[7]
Last updated: 12/15/2014

References
  1. Coats Disease. NORD. October 2012; http://www.rarediseases.org/rare-disease-information/rare-diseases/byID/837/viewFullReport.
  2. Del Longo A. Coats disease. Orphanet Encyclopedia. September 2004; http://www.orpha.net/data/patho/Pro/en/Coats-FRenPro1645.pdf.
  3. A. Del Longo. Coats disease. Orphanet. September 2004; http://www.orpha.net/consor/cgi-bin/OC_Exp.php?lng=EN&Expert=190. Accessed 12/2/2011.
  4. Coats Disease. OMIM. May 2013; http://omim.org/entry/300216.
  5. Senior Loken Syndrome. Genetics Home Reference. June 2012; http://ghr.nlm.nih.gov/condition/senior-loken-syndrome.
  6. Coats Plus Syndrome. Genetics Home Reference. April 2014; http://ghr.nlm.nih.gov/condition/coats-plus-syndrome.
  7. Shields JA, Shields CL, Honavar SG, Demirci H, Cater J. Classification and management of Coats disease: the 2000 Proctor Lecture. American Journal of Ophthalmology. May 2001; 131(5):572-583.


Other Names for this Disease
  • Retinal telangiectasis
See Disclaimer regarding information on this site. Some links on this page may take you to organizations outside of the National Institutes of Health.