Inherited FGFR2 mutation in a Chinese patient with Crouzon syndrome and luxation of bulbus oculi provoked by trauma: a case report

Abstract

Background: Crouzon syndrome (CS), which results from fibroblast growth factor receptor 2 mutations, is associated with craniosynostosis, exophthalmos, and other symptoms. Herein, we report the genetic abnormalities detected in a Chinese family with autosomal dominant CS, combined with luxation of the eyeball. This luxation was a consequence of the trauma to the shallow orbits. Case presentation: The proband was a 4-year-old boy. He accidentally fell, following which luxation of the bulbus oculi occurred immediately. Computed tomography and magnetic resonance imaging clearly revealed ocular proptosis. Upon physical examination, the proband, his father, and grandfather had ocular proptosis, shallow orbits, and mid-face hypoplasia. However, their hands and feet were clinically normal. Genomic DNA was extracted from the peripheral blood through a polymerase chain reaction performed for the target sequence. Genetic assessments revealed a heterozygous missense mutation (c.1012G > C, p.G338R) in exon 10 of the human FGFR2, cosegregated with the disease phenotype in this family. These findings confirmed the diagnosis of CS. Discussion: CS is usually caused by FGFR2 mutations. While there are a few reports of luxation of the bulbus oculi in Chinese families with CS, the ocular proptosis, shallow orbits, combined with luxation of eyeball after trauma observed in this patient were particularly interesting. Our findings enhance the current knowledge of traumatic luxation concomitant with CS.

Crouzon syndrome and the eye: An overview

“…Several researchers have detected a number of mutations in diseased individuals, with an estimate of around 60 FGFR-2 mutations identified. [ 13 ] Ig III mutations lead to an abnormally high activity of tyrosine kinase but similar activity has likewise been described in IG I mutations by Sharma et al . [ 32 ] in Cys62Ala mutation.…”

“…Yang et al . [ 13 ] reported a case of globe subluxation in a young child with CS, after an accidental fall. Edema of periorbital tissue in an already shallow orbit was the presumed cause for subluxation in this case.…”

“…[ 32 ] in Cys62Ala mutation. A heterozygous missense mutation in exon 10 (c.1012G>C, p.G338R) of FGFR-2 has recently been reported by Yang[ 13 ] et al . in family members of an individual affected with CS.…”

Novel Gene Mutations Associated with Crouzon Syndrome

“…The FGFR2 protein plays a crucial role in the development of bones before birth (embryonic development). [16] Early signals by the protein directs immature cells in the developing embryo to become bone cells and form the head, hands, feet, and other tissues. [17] Several isoforms of the FGFR proteins have also been identified in different tissues, whose patterns may change throughout growth and development.…”

Comprehensive management of Crouzon syndrome: A case report with three-year follow-up

“…This syndrome is caused by a heterogenous mutation in the gene encoding fibroblast growth factor receptor 2 (FGFR2) on chromosome 10q26 (OMIM, #123500, Jabs, 1994). The FGFR2 mutations determine Crouzon syndrome pathogenesis and currently 60 different mutations have been identified, out of which 95% muta-tions occur in exon 8 and 10 of this gene in Crouzon syndrome (Yang et al, 2019).…”