Axenfeld-Rieger syndrome

Axenfeld‑Rieger syndrome is a group of disorders that primarily affect the development of the eye. Common ocular features include abnormalities of the cornea and abnormalities of the iris. People with this syndrome may have an off‑center pupil (corectopia) or extra openings in the eye that may appear as multiple pupils (polycoria. Approximately 50% of individuals with this syndrome develop glaucoma, a condition that increases the pressure inside the eye and may cause vision loss or blindness.

Although Axenfeld‑Rieger syndrome is primarily an eye disorder, it can also affect other parts of the body. Most individuals with this syndrome have distinctive facial features, and many also have dental problems, including unusually small teeth (microdontia) or fewer than normal teeth (oligodontia). Some individuals have extra folds of skin around the belly button, heart defects, or other rare congenital abnormalities.

There are three types of Axenfeld‑Rieger syndrome, each with a different genetic cause.

• Axenfeld‑Rieger syndrome type 1 is caused by mutations in the PITX2 gene.
• Axenfeld‑Rieger syndrome type 3 is caused by mutations in the FOXC1 gene.
• The gene responsible for Axenfeld‑Rieger syndrome type 2 is unknown but is located on chromosome 13.

Axenfeld‑Rieger syndrome follows an autosomal dominant pattern of inheritance.

Symptoms

Axenfeld‑Rieger syndrome is an eye disorder. Individuals with this condition typically have abnormalities of the cornea, the clear covering on the front of the eye. They may have a cloudy cornea or a posterior embryotoxon, a condition in which a prominent ring is visible around the outer edge of the cornea. They may also have abnormalities of the iris, the colored part of the eye. One pupil may be displaced (corectopia), pupils may be abnormally large or small, or there may be additional pupils (polycoria).

About 50% of individuals with this syndrome develop glaucoma, a disease that increases intraocular pressure and may lead to vision loss or blindness. Individuals may also have strabismus (crossed eyes), cataract (clouding of the lens), macular degeneration (a disorder that causes central vision loss), or coloboma (a hole in an ocular structure).

Although Axenfeld‑Rieger syndrome is primarily an eye disorder, affected individuals may have symptoms involving other body parts, mainly the teeth and facial bones.
Dental findings include:

• cone‑shaped teeth (peg‑shaped incisors)
• missing teeth (oligodontia)
• small teeth (microdontia)
• abnormal spacing of teeth

Facial bone findings may include an underdeveloped jaw, protruding lower lip, and widely spaced eyes.
 Other features may include skin folds around the belly button, congenital heart defects, or other rare malformations.

Treatment

Treatment depends on the symptoms.

 If glaucoma is present, the goal is to reduce intraocular pressure (IOP). Annual ophthalmologic examinations should include specific tests to detect glaucoma. If glaucoma develops, eye drops are usually recommended before surgery. Medications that may be prescribed include aqueous suppressant drugs (beta‑blockers, alpha‑agonists, and carbonic anhydrase inhibitors). Alpha‑agonists should be used with caution in young children due to possible neurological side effects.

If surgery is necessary, trabeculectomy is the treatment of choice. Laser surgery may also be indicated.

Individuals with corectopia or polycoria may experience photophobia, so contact lenses may be helpful.

If additional findings are present, treatment depends on the specific symptoms and may include facial or dental surgery, cardiac surgery, or corrective surgery for hypospadias. Short stature caused by growth hormone deficiency may be treated with growth hormone therapy.

• chyby rohovky
• chyby dúhovky
• corectopia
• viacpočetné zrenice (polykória)
• glaukóm (asi u 50%)
• možnosť strabizmu (škúlenie)
• možnosť katarakty (zakalená šošovka)
• výrazné črty tváre (nedostatočne vyvinutá čeľusť, vyčnievajúca spodná pera a oči veľmi vzdialené od seba)
• problémy so zubami (neobvykle malé zuby - mikrodoncia)
• niekedy srdcové chyby