Classic lattice corneal dystrophy associated with monoclonal gammopathy after exclusion of a TGFBI mutation.

PURPOSE: The purpose of this study was to report the association of phenotypic features characteristic of lattice corneal dystrophy (LCD) with a monoclonal gammopathy of undetermined significance (MGUS) after exclusion of a coding region mutation in transforming growth factor beta-induced (TGFBI) gene.

DESIGN

Case report.

METHODS

Slit-lamp examination and collection of DNA for TGFBI screening were performed. A systemic evaluation was also performed to evaluate for conditions associated with systemic amyloidosis.

RESULTS

A 65-year-old man demonstrated bilateral linear branching corneal stromal opacities characteristic of classic LCD. No mutations were found in any of the 17 exons of TGFBI or in the intron-exon boundary regions. Four previously described single nucleotide polymorphisms were identified: c.698C>G (p.Leu217Leu; rs1442), c.1028A>G (p.Val327Val; rs1054124), c.1416C>T (p.Leu472Leu; rs1133170), and c.1667T>C (p.Phe540Phe; rs4669). Serum protein electrophoresis revealed the presence of a monoclonal spike, and based on the results of additional investigations, the patient was diagnosed with MGUS.

CONCLUSIONS

Although the presence of bilateral thin branching lattice lines in the corneal stroma is characteristic of classic LCD, this distinctive phenotype may not be associated with a TGFBI coding region mutation but instead with a myeloproliferative disorder such as MGUS. Therefore, appropriate genetic and serologic testing should be performed in patients with a late-onset LCD phenotype in the absence of a positive family history.