Case Reports

Bilateral progressive keratoconus, severe pectus excavatum, and generalized musculoskeletal dystrophy

Case Report Details

First Author: G.Kondylis GREECE

Co Author(s):    S. Palioura   O. Klavdianou                 

Abstract Details

Purpose:

To report a case of bilateral progressive keratoconus in a patient with severe pectus excavatum, generalized muscular weakness and skeletal deformities.

Setting:

Athens Vision Eye Institute, Cornea Service, Athens, Greece

Report of Case:

A 31-year-old man with history of G6PD deficiency presented for evaluation of decreased vision in both eyes for the last year. His best-corrected vision was 20/63+2 in the right eye and 20/200 in the left eye. Topography revealed an asymmetric bowtie configuration and tomography a significant posterior elevation, consistent with keratoconus. Upon further questioning the patient reported generalized muscular weakness and skeletal deformities since childhood for which he had undergone several corrective surgeries in the knees and hips. He is of very short stature and has radiographically visible spinal stenosis as well as scoliosis, kyphosis of the thoracic spine and spondylolisthesis. All joints have limited mobility and radiographically visible abnormal architecture. The knee joint has significant genu valgum and his fingers appear deformed. The patient also has marked pectus excavatum with cardiac and large vessel displacement. This constellation of findings does not fit into any known genetic condition and thus the patient underwent whole exome sequencing. Whole exome sequencing identified two gene mutations, namely a heterozygous variant in the Cartilage Oligomeric Matrix Protein (COMP) gene and a similar one in the RIMS1 gene. Pathogenic variants in the RIMS1 gene are associated with autosomal dominant cone-rod dystrophy type 7, thus the patient underwent electrophysiological examination of vision. Electrophysiological tests were normal and the RIMS1 gene variant was considered as of no significance. The pathogenic variant found in the COMP gene, an amino acid change from Asp to Gly at position 349, has been described as disease causing for pseudoachondroplasia, a finding that could possibly explain the skeletal deformities of the patient.

Conclusion/Take Home Message:

This is the first case reported in the literature of bilateral progressive keratoconus associated with severe pectus excavatum, spinal stenosis and generalized musculoskeletal dystrophy. Whole exome sequencing identified a mutation in the COMP1 gene, thus associating the presence of bilateral keratoconus with pseudoachondroplasia.

Financial Disclosure:

None