Abstract
Purpose :
The pathology of Pierson syndrome is poorly understood, particularly regarding the ocular manifestations. Based on current knowledge, patients display primarily anterior segments findings, notably microcoria. Current literature also suggests that missense mutations result in milder clinical disease while frameshift mutations result in severe defects. We present the course and genetic analysis of a patient with Pierson syndrome whose case challenges these suggestions. Data was collected via retrospective chart review.
Methods :
DNA was isolated from ethylenediaminetetraacetic acid anti-coagulated peripheral blood. A short segment of interest on chromosome 3p21.31 was amplified by polymerase chain reaction using specific oligonucleotide primers. The products were then sequenced using a fluorescence-based cycle sequencing protocol. Extension products were subsequently size-fractioned on an Applied Biosystems®3130 Genetic Analyzer.
Results :
A 23-month-old female presented to the pediatric ophthalmologist with significant posterior defects including peripapillary atrophy, optic disc atrophy and retinal thinning. No microcoria was present. The patient developed an inferior retinal detachment in the right eye at 27 months of age, despite receiving bilateral prophylactic barrier retinopexy. Standard surgical intervention was performed. At five years of age, she suffered a total retinal detachment in the left eye. Again, standard surgical intervention was performed.
Genetic Testing
Genetic testing of the patient revealed an adenine to guanine mutation translation at base pair 440 in both copies of the LAMB2 gene. This mutation resulted in a histidine to arginine exchange at amino acid 147.
Conclusions :
A mere three published papers in major ophthalmology journals exist regarding Pierson syndrome. The presented patient was found to be homozygous for a missense mutation of LAMB2, which resulted in very severe and predominantly posterior segment ophthalmic pathology. This, in addition to lacking microcoria, made her presentation unique. This case report adds valuable clinical and genetic data to the literature. Furthering such knowledge can help in the development of therapeutic options and the ability of the provider to provide an accurate prognosis.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.