Phenotype‐genotype relationship of TGFβI corneal dystrophies among Polish families

Abstract

Abstract Purpose To analyze clinical, histologic and genetic features of TGFβI corneal dystrophies. Methods 43 patients from 14 unrelated families were recruited. The clinical examination consisted of inheritance pattern and medical history analysis, slit lamp biomicroscopy and anterior segment optical coherence tomography. Light microscopy was performed on 9 corneal specimen obtained during keratoplasty. PCR and sequencing of all coding exons of TGFβI was performed. Results Based on the study we diagnosed 3 families with GCD1. The clinical pattern of all families with GCD1 was similar. OCT revealed hiperreflective focal changes in the stroma and distinct irregularity of Bowman layer. Histological analysis showed Masson trichrome positive deposits. R555W mutation was revealed. 1 family was diagnosed with TBCD. We noticed increased reflectivity, irregularity of Bowman layer and increased central corneal thickness (CCT) to 608 µm during OCT exam. R555Q mutation was revealed. Two mutations were detected in patients with LCD. Patients from 8 families had R124C mutation. Those patients had thin lattice lines in anterior stroma and CCT increased to 628 µm. Two families had atypical LCD with H626R mutation. There were differences in phenotype between those two families. The first one had asymmetric, late‐onset dystrophy with thin fragile lines extending to DM on OCT scan, while the other family had both eyes involved with thick, distinct lines accompanied with stromal haze, also extended to DM. Corneal buttons of LCD patients showed Congo red positive deposits. Conclusion Among Polish families R124C TGFBI mutation is the most common genetic pattern coexisting clinically with increased CCT. Genetic analysis plays an important role in corneal dystrophy diagnosis.