Werner syndrome with refractory cystoid macular edema and immunohistochemical analysis of WRN proteins in human retinas

OCT and ERG Techniques in High-Throughput Phenotyping of Mouse Vision

The purpose of the study is to demonstrate coherent optical tomography and electroretinography techniques adopted from the human clinical practice to assess the morphology and function of the mouse retina in a high-throughput phenotyping environment. We present the normal range of wild-type C57Bl/6NCrl retinal parameters in six age groups between 10 and 100 weeks as well as examples of mild and severe pathologies resulting from knocking out a single protein-coding gene. We also show example data obtained by more detailed analysis or additional methods useful in eye research, for example, the angiography of a superficial and deep vascular complex. We discuss the feasibility of these techniques in conditions demanding a high-throughput approach such as the systemic phenotyping carried out by the International Mouse Phenotyping Consortium.

Optical coherence tomography findings in three patients with Werner syndrome

Background

Werner syndrome is a rare, autosomal recessive disorder characterised by premature aging. It is a typical hereditary progeroid syndrome that can be difficult to diagnose owing to its rarity and the similarity of some of its symptoms, such as juvenile cataracts, to other common ophthalmologic conditions. Early onset of bilateral cataracts is currently used as the ophthalmological feature for Werner syndrome; however, ophthalmologists often find performing a detailed examination of the medical history and genetic testing for Werner syndrome at the time of an ophthalmologic consultation challenging. If a unique ocular finding was observed on ocular examinations in cases of juvenile bilateral cataracts, we could consider Werner syndrome as a differential diagnosis. 

Case presentation

We documented the cases of three patients with Werner syndrome in whom thinning of the retina in the retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) were observed using optical coherence tomography (OCT). Visual field tests revealed the loss of visual field mainly owing to glaucoma.

The thinnig of the choroidal thickness (CT) in three patients was also observed using enhanced depth imaging (EDI)-OCT.

Conclusions

Three patients have thinning of the RNFL, GCC, and choroidal thickness and the loss of visual field. These findings suggest the need for including Werner syndrome in the differential diagnosis when patients presenting with juvenile cataracts of unknown cause also show abnormal retinal and choroidal thinning in the OCT images.

Primary Bullous Keratopathy in a Patient With Werner Syndrome Treated With Corneal Transplant

Here, we present, to the best of our knowledge, the first case of Werner syndrome with corneal blindness due to bilateral primary bullous keratopathy. Werner syndrome is a rare autosomal recessive disorder characterized by features of premature aging, insulin-dependent diabetes mellitus, osteoporosis, atherosclerosis, hypergonadotrophic hypogonadism, hypertriglyceridemia, scleroderma-like skin changes, and sarcomas. Among ocular manifestations, cataracts, cystoid macular edema, and retinal detachment have been reported. Because these patients show features of premature aging, they have decreased corneal endothelial function and delayed fibroblast growth. To date, there are few reports of wound dehiscence, bleb formation, and bullous keratopathy following surgical insult that have usually occurred after cataract surgery in patients with Werner syndrome. There have been no reports in the literature regarding Werner syndrome presenting with primary corneal decompensation without any inciting factor. Our patient with Werner syndrome had primary bilateral bullous keratopathy and bilateral corneal blindness for 10 years and was eventually rehabilitated by corneal transplant. Hence, this case highlights the importance of early referral of such patients to the ophthalmologist for prompt diagnosis and early treatment so that blindness could be avoided.

The ophthalmic diagnosis and management of four siblings with Werner syndrome

INTRODUCTION

Werner syndrome is a rare autosomal recessive disorder caused by mutations in the Werner syndrome WRN gene, on chromosome 8. Those affected manifest early the features of ageing.

DISCUSSION

Cataract surgery is prone to post-operative complications in those with Werner syndrome. The development of cystoid macular oedema (CMO) is likely multifactorial. Patients with WS have diabetes mellitus type 2 which can contribute to macular oedema. There is a deposition of abnormal WRN proteins in the macula which also predisposes to macular oedema. The trauma of cataract surgery appears to be the main stimulus for the development of CMO. CMO may, as a result, be difficult to manage in Werner syndrome patients.

CONCLUSION

Further study is needed to elucidate the precise role of retinal WRN protein expression in the development of CMO in those with Werner syndrome. A tailored and more successful approach to the treatment of CMO in such patients may result.