Individual phenotypic variances in a family with Avellino corneal dystrophy.

Background: Avellino corneal dystrophy (ACD) is an autosomal dominant disorder, characterized by the presence of deposits in the anterior stroma, and results from a specific mutation (R124H) in the transforming growth factor beta-induced gene (TGFBI). This report presents corneal dystrophy of the Bowman layer as a rare phenotypic appearance of ACD and a high intra-familial variability of phenotype in patients with ACD.

Methods: A 56 year-old Caucasian woman with recurrent corneal erosions was diagnosed with corneal dystrophy of the Bowman layer after a clinical examination. Optical coherence tomography of the anterior segment (AS-OCT) mainly demonstrated deposits in the Bowman layer and a few deposits in the superficial stroma. Her son, a 36 year-old man, has a typical clinical presentation of ACD with all the deposits arranged in stromal layers. In his case, the opacities resemble snowflakes between the granular deposits, and AS-OCT shows large, snowflake-like deposits in the superficial and deep stroma without accumulation in the Bowman layer. Genetic screening in both cases shows the heterozygous R124H mutation in the TGFBI gene.

Conclusions: The clinical finding of the granular-lattice corneal dystrophy in which deposits are located in the Bowman layer may be an atypical presentation of ACD. This paper demonstrates a high degree of variability in the quantity and form of deposits between ACD heterozygotes. This is the first description of Avellino corneal dystrophy in the Balkans and in Serbia.