Coexistence of MRCS syndrome, extremely long axis and exfoliation syndrome: a case report and literature review

BACKGROUND: The coexistence of MRCS (microcornea, retinal dystrophy, cataract, and posterior staphyloma) syndrome and extremely long axis is rare since microcornea frequently accompanies with diminution of entire anterior segment and occasionally the whole globe. In the case presented here, combination of these two elements were identified, together with XFS (exfoliation syndrome). CASE PRESENTATION: A 66-year-old Han Chinese woman presented for consultation due to impaired vision which accompanied throughout her entire life span and worsened during the last 2 years. Combination of MRCS syndrome and extremely long axial length was evidently diagnosed in both eyes, with XFS confirmed in her right eye, but mutation screening failed to identify disease-causing sequence variants in some specific genes reported previously, including BEST1 and ARL2. However, likely pathogenic mutations in FBN2 gene were identified. Bilateral cataract phacoemulsification without intraocular lens implantation was performed using scleral tunnel incision and under general anesthesia. At 3-month follow-up, ocular recovery of the patient was satisfactory. CONCLUSIONS: The case presented here exhibited rare coexistence of MRCS syndrome, extremely long axis and XFS. The complexity of her ocular abnormalities brought challenges to surgical management, in which multidisciplinary collaboration is often required. Furthermore, the genetic analysis in this case yielded a possible novel candidate gene for MRCS syndrome and provided evidence in support of genetic heterogeneity in this phenotype.