Peters Anomaly

Clinical Characteristics
Ocular Features: 

Peters anomaly occurs as an isolated malformation but also as a feature of other syndromes.  It is often unilateral.  A wide variety of other ocular findings may occur with Peters anomaly as well. Here we limit our description to 'simple' Peters anomaly in which the findings are limited to the eye having the classic findings of adhesions of the iris to the posterior cornea and a central or paracentral corneal leukoma.  The lens may also be adherent to the cornea and is often opacified to some degree.  Descemet's membrane and portions of the posterior stroma are usually missing as well.  Glaucoma is frequently present.  Importantly, there is a wide range in the presentation of clinical features.

Systemic Features: 

Peters anomaly is a frequent feature of numerous syndromes, both ocular and systemic, among them the Peters-plus (261540) syndrome (sometimes called the Kivlin-Krause (261540) syndrome) and has been reported in a case with aniridia (106210).

Genetics

Isolated Peters anomaly usually occurs in an autosomal recessive pattern but autosomal dominant patterns have been reported as well.  The recessive disorder may be caused by a mutation in several genes, notably PAX6, PITX2,  CYP1B1, FOXC1, and FOXE3.  The latter gene is also mutated in anterior segment mesenchymal dysgenesis (107250) and congenital primary aphakia (610256).  The variety of clinical features are likely the result of a disruption in some common pathway or pathways.  Mutations in B3GALTL associated with the Peters-Plus syndrome have not been identified in isolated Peters anomaly.

This is a genetically and clinically heterogeneity condition as whole genome sequencing reveals numerous additional gene mutations in patients with both syndromic and isolated Peters anomaly.

PITX2 is also mutated in ring dermoid of the cornea (180550) and in Axenfeld-Rieger syndrome type 1 (180500).  PAX6 mutations also cause diseases of the cornea, fovea, optic nerve and iris.

Treatment
Treatment Options: 

Glaucoma is the most serious threat to vision on Peters anomaly but also the most difficult to treat.  Less than a third of patients achieve control of intraocular pressure even with the most vigorous combinations of therapy.  Corneal opacities can be treated with transplantation but the prognosis is often guarded when glaucoma is present.

From eye bank and other data, it has been estimated that 65% of penetrating keratoplasties in infants for visually significant congenital corneal opacities are performed in patients with Peters anomaly. 

References
Article Title: 

Whole exome sequence analysis of Peters anomaly

Weh E, Reis LM, Happ HC, Levin AV, Wheeler PG, David KL, Carney E, Angle B, Hauser N, Semina EV. Whole exome sequence analysis of Peters anomaly. Hum Genet. 2014 Sep 3. [Epub ahead of print].

PubMed ID: 
25182519

References

Weh E, Reis LM, Happ HC, Levin AV, Wheeler PG, David KL, Carney E, Angle B, Hauser N, Semina EV. Whole exome sequence analysis of Peters anomaly. Hum Genet. 2014 Sep 3. [Epub ahead of print].

PubMedID: 25182519

Kurilec JM, Zaidman GW. Incidence of Peters Anomaly and Congenital Corneal Opacities Interfering With Vision in the United States. Cornea. 2014 Jun 24. [Epub ahead of print].

PubMedID: 24977984

Weh E, Reis LM, Tyler RC, Bick D, Rhead WJ, Wallace S, McGregor TL, Dills SK, Chao MC, Murray JC, Semina EV. Novel B3GALTL mutations in classic Peters Plus syndrome and lack of mutations in a large cohort of patients with similar phenotypes. Clin Genet. 2013 Jul 24. [Epub ahead of print].

PubMedID: 23889335

Bhandari R, Ferri S, Whittaker B, Liu M, Lazzaro DR. Peters anomaly: review of the literature. Cornea. 2011 Aug;30(8):939-44. Review.

PubMedID: 21448066

Sawada M, Sato M, Hikoya A, Wang C, Minoshima S, Azuma N, Hotta Y. A case of aniridia with unilateral Peters anomaly. J AAPOS. 2011 Feb;15(1):104-6.

PubMedID: 213997818

Yang LL, Lambert SR, Lynn MJ, Stulting RD. Surgical management of glaucoma in infants and children with Peters' anomaly: long-term structural and functional outcome. Ophthalmology. 2004 Jan;111(1):112-7.

PubMedID: 14711722

Traboulsi EI, Maumenee IH. Peters' anomaly and associated congenital malformations. Arch Ophthalmol. 1992 Dec;110(12):1739-42. Review.

PubMedID: 1463415