Genotype and Anterior Segment Phenotype in a Cohort of Turkish Patients with Lamellar Ichthyosis

To evaluate the ocular surface and topography findings of lamellar ichthyosis, and to investigate the correlation of these findings with mutations in TGM1, CYP4F22 and NIPAL4 genes.

Twelve patients with lamellar ichthyosis were evaluated. Routine ophthalmic examination including Schirmer 1, tear break-up time and ocular surface staining score, topography, and genetic evaluation for coding exons of TGM1, NIPAL4 and CYP4F22 genes were performed.

The mean age of the patients was 19.75 ± 9.15 (range, 4-31) years. Mean Schirmer 1 scores of the right and the left eyes were similar (18.75 ± 3.10 mm). Mean tear break-up time of the right and the left eyes were 6.58 ± 2.74, 6.58 ± 3.02 seconds, respectively. Mean ocular surface staining grade was 0.36 ± 0.20 in the right, and 0.39 ± 0.17 in the left eyes. Keratoconus was detected in two patients. Two patients with bilateral cataract formation were found. Genetic sequencing revealed that one case had homozygous R326X mutation in the CYP4F22 gene, two cases had homozygous A176D mutation in the NIPAL4 gene, and three had homozygous M1T mutation in the same gene. Mutations were detected in patients with keratoconus and in a patient with bilateral cataract formation.

In lamellar ichthyosis, eyelid malformations together with decreased tear break-up time might cause sight-threatening complications. Genetic counseling for mutations might enable the physician to predict the possibility of upcoming ocular problems in lamellar ichthyosis patients.