Rare Systemic Association Of Keratoconus In Pediatric Patients

Keratoconus is an ectatic corneal disease that usually appears in adolescents and young adults, which can also be associated with systemic pathologies, such as connective tissue disorders. Osteogenesis imperfecta (OI) is a genetic disorder caused by mutations in collagen-encoding genes and in genes involved in bone metabolism. It results in frequent fractures and bone fragility, associated with blue sclera, dentinogenesis imperfecta, hearing deficits, ligaments and skin hyperlaxity. Certain types of OI involve thin corneas, myopia, and keratoconus.

F.I. is a 15 years-old male, presenting for slowly decreasing visual acuity in the right eye (RE). Patient history includes repeated bone fractures following minor impact, progressive hypoacusia over the last 3 years, abnormal dentition and penetrating ocular trauma 7 years prior in the left eye (LE). Heredocolateral antecedents include one 9 years-old sister, with the ophthalmological diagnosis of blue sclerae, hyperopia and regular astigmatism.

Ophthalmological examination includes autorefractometry (RE -14.00 D sphere <> -9.00 D cylinder at 110°, LE it could not be measured), visual acuity (RE uncorrected visual acuity 0.03, best corrected visual acuity 0.16 with -12 Dsph; LE no light perception), normal intraocular pressure. Slit lamp examination revealed RE: blue scleral discoloration, Fleischer ring, Vogt lines, 2 anterior stromal opacities, in the temporal half of the cornea, LE: large corneal leukoma, phthisis bulbi. Fundus examination revealed RE tilted disc, peripapillary chorioretinal atrophy, attached retina, and LE could not be performed. RE central corneal thickness is 360 µm and corneal topography revealed marked astigmatism.

Corroborating clinical and paraclinical data, the patient was diagnosed with RE stage IV keratoconus, LE phthisis bulbi, corneal leukoma, and a presumptive diagnosis of osteogenesis imperfecta. Corneal crosslinking was performed in the right eye, and the patient was recommended spectacles for visual correction, artificial tears, avoiding eye rubbing and trauma. Furthermore, the patients and his sister were recommended genetic testing and counseling. Immediate evolution was favorable, with improved visual acuity using glasses, and stabilization of keratoconus. Long-term prognosis is reserved, due to the underlying disease: keratoconus may progress and the risk of ocular injury after minor trauma is higher compared to the general population.

Keratoconus is not a common manifestation of OI, while blue sclerae, thin corneas and myopia are more frequently found in this disease. The distinctive feature of this case consists of this infrequent association, and the late systemic diagnosis of OI, which followed the suspicion raised by the ophthalmologist.

Acknowledgements: All authors had equal contributions.