Axenfeld-Rieger Syndrome

Excerpt

Axenfeld-Rieger syndrome (ARS) was previously known as Axenfeld anomaly; the latter term was used to describe one of three subvariants of this spectrum of disease. ARS is a disease that encompasses anterior segment ocular dysgenesis in addition to systemic abnormalities such as dental, cardiac, craniofacial, and abdominal wall defects. ARS commonly correlates with 6p25 distal microdeletion. However, different presentations of this syndrome may share links with other genetic loci such as 4q25 or 13q14. Several genes have associations with ARS, including FOXC1, FOXC2, and FKHL7.

This spectrum of anomalies was initially described by Axenfeld and Rieger in the early 20th century, as a set of ocular abnormalities affecting mostly the anterior segment of the eye with conditions such as iris hypoplasia and polycoria, among others. Some authors still subcategorize ARS in three terms, commonly with overlapping presentations. Axenfeld anomaly is used to describe patients who present mostly with disorders associated with an anteriorly displaced and prominent Schwalbe line, a condition also known as “posterior embryotoxon.” Rieger anomaly characteristically presents with central iris defects, such as irregular pupils with stromal hypoplasia, and Rieger syndrome describes patients with Rieger anomaly in addition to systemic features.