Retinitis pigmentosa associated with Fuchs' heterochromic uveitis

Inherited retinal disease-associated uveitis

Inherited retinal diseases (IRDs) are genetic disorders characterized by progressive photoreceptor function loss, often leading to significant visual impairment. Uveitis has been increasingly recognized in the clinical course of some IRDs. Despite advances in understanding the genetic causes and pathophysiology of IRDs, gaps remain in understanding the roles of inflammation and autoimmunity in IRD and IRD-associated uveitis. This review discusses IRD-associated uveitis, including anterior, intermediate, posterior, and panuveitis, as well as complications such as cystoid macular edema and retinal vasculitis. In patients with IRD-associated uveitis, mutations affecting protein function in cilia or photoreceptor outer segments suggest a universal autoimmune mechanism triggered by the immunogenicity of shedding photoreceptor discs. Notably, in patients where uveitis is the initial sign, CRB1 mutations are often implicated, likely due to the compromised blood-retina barrier function or alterations in the external limiting membrane. Other mechanisms leading to uveitis preceding IRD diagnosis include ALPK1 mutations, which activate the proinflammatory NF-κB pathway, CAPN5 mutations, which lead to dysfunction of the innate and adaptive immune systems, and VCAN1 mutations, which elicit immunogenicity due to irregularities in vitreous modeling. Understanding these mechanisms could enhance the development of innovative treatments that target personalized inflammation pathways in IRDs.

Retinitis Pigmentosa: Current Clinical Management and Emerging Therapies

Retinitis pigmentosa (RP) comprises a group of inherited retinal dystrophies characterized by the degeneration of rod photoreceptors, followed by the degeneration of cone photoreceptors. As a result of photoreceptor degeneration, affected individuals experience gradual loss of visual function, with primary symptoms of progressive nyctalopia, constricted visual fields and, ultimately, central vision loss. The onset, severity and clinical course of RP shows great variability and unpredictability, with most patients already experiencing some degree of visual disability in childhood. While RP is currently untreatable for the majority of patients, significant efforts have been made in the development of genetic therapies, which offer new hope for treatment for patients affected by inherited retinal dystrophies. In this exciting era of emerging gene therapies, it remains imperative to continue supporting patients with RP using all available options to manage their condition. Patients with RP experience a wide variety of physical, mental and social-emotional difficulties during their lifetime, of which some require timely intervention. This review aims to familiarize readers with clinical management options that are currently available for patients with RP.

Progression of retinal pigmentation mimicking unilateral retinitis pigmentosa after bilateral pars planitis: a case report

Background

To report our findings in a young patient with unilateral retinitis pigmentosa (RP)-like appearance who developed pigmentary changes in his left retina after an episode of bilateral pars planitis.

Case presentation

A 17-year-old man presented with 6 months of blurry vision in both eyes. He was diagnosed with bilateral pars planitis. Progressive, intraretinal bone crepuscule pigmentation developed in his left retina during the following three months. An electroretinogram showed subnormal response only in the left eye, suggesting the diagnosis of unilateral pseudoRP.

Conclusion

An inflammatory disease like pars planitis can accelerate the pigmentation of the retina and mimic a RP in young patients. Causes of pseudoRP may be considered, especially in those rare cases with unilateral affection.

Bilateral uveitis and Usher syndrome: a case report

Introduction

Usher syndrome is a genetically heterogeneous condition and represents the most common cause of inherited combined vision and hearing loss. Deficits manifest as sensorineural hearing loss that typically develops at a young age and retinitis pigmentosa that can lead to peripheral vision loss and night blindness. As a result, this syndrome can have a significant impact on a patient’s quality of life.

Previous studies have described an association between Usher syndrome and Fuchs’ heterochromic iridocyclitis, a form of non-granulomatous uveitis that generally presents in a unilateral manner. We present a rare finding of bilateral uveitis and, to the best of our knowledge, the first report of granulomatous uveitis as a feature in a patient with Usher syndrome.

Case presentation

A 45-year-old Caucasian woman with a known history of retinitis pigmentosa presented to our clinic with suspected Usher syndrome, given her report of long-standing hearing loss. Aside from a mild loss in visual acuity, our patient was otherwise asymptomatic. Visual field testing, audiology and electroretinography findings supported the diagnosis of Usher syndrome. With slit lamp examination she was found to have bilateral keratic precipitates, with large, greasy-white, mutton-fat keratic precipitates on the endothelial surface of her left eye. A thorough work-up that included blood tests and imaging was negative for an alternative cause of her uveitis.

Conclusion

We present a rare finding of bilateral uveitis and what we believe to be the first reported instance of mutton-fat keratic precipitates and granulomatous uveitis as a feature in a patient with Usher syndrome. By identifying atypical presentations of the disease, we hope to contribute to the range of ophthalmic conditions that may be seen in association with Usher syndrome.

Nongranulomatous anterior uveitis in a patient with Usher syndrome

A 34-year-old female with Usher syndrome, but no family history of similar illness, presented with complaints of vision reduction, redness, and photophobia. Biomicroscopic examination showed mildly injected conjunctivae bilateral, small, round keratic precipitates; bilateral +2 cells with no flare reaction in the anterior chamber; and bilateral posterior subcapsular cataracts. No associated posterior synechiae, angle neovascularization, or iris changes were detected; normal intraocular pressures were obtained. Fundus examination demonstrated waxy pallor of both optic nerves, marked vasoconstriction in retinal vessels, and retinal bone spicule pigment formation, with a normal macula. Electroretinography confirmed the diagnosis of retinitis pigmentosa, optical coherent tomography was normal and otolaryngology consultation was conducted. To our knowledge, an association between Usher syndrome and bilateral nongranulomatous anterior uveitis has not been previously reported, and our purpose is to report this association.

Usher syndrome associated with Fuchs' heterochromic uveitis: a case report

We report a case of Usher syndrome in association with unilateral Fuchs' heterochromic uveitis.

Corneal astigmatism in unilateral Fuchs heterochromic iridocyclitis

PURPOSE

To analyze the results of scanning slit topography in both eyes of patients with unilateral Fuchs heterochromic iridocyclitis (FHI).

METHODS

A noninterventional, case-controlled study was conducted with 30 patients with unilateral FHI. Corneal topographic parameters, obtained with the Orbscan II (Bausch & Lomb), were compared between the two eyes and analyzed statistically. The same number of age-matched normals was enrolled as a control group.

RESULTS

Thirty patients were enrolled in this study. The mean age was 33.3 years ± 10.6 (SD). The mean Sim K astigmatism was 1.65 ± 1.27 diopter in the FHI eyes and 0.88 ± 0.52 diopter in the normal eyes (p = .001).

CONCLUSION

Corneal astigmatism is a common finding in patients with FHI and disparity of corneal astigmatism between the two eyes can be considered a sign of the unilateral form of this disease.

Usher syndrome associated with Fuchs' heterochromic uveitis

BACKGROUND

The purpose of this study is to report two new cases of Usher syndrome associated with Fuchs' heterochromic uveitis (FHU), to confirm our previous observation of the association between FHU and retinitis pigmentosa (RP), and to evaluate if FHU is particularly associated with Usher syndrome.

METHODS

Retrospective medical record review of all new RP cases at Hadassah Medical Center between the years 2000 and 2007, review of our previously published data, and a meta-analysis of published relevant articles in peer reviewed journals.

RESULTS

During the time frame of the study we diagnosed 58 new cases of RP, of whom one male and one female had the typical findings of FHU, and both had Usher syndrome type II. The difference in the occurrence of FHU between the 616 controls and the patients with RP was significant (p = 0.0073, Fisher's exact test). In our combined data, FHU occurred only in two types of RP; RP simplex with an incidence of 0.57%, and Usher syndrome with an incidence of 13.5%. This difference between the incidence of FHU in patients with Usher syndrome and other types of RP was significant (p < 0.0001, Fisher's exact test). Adding up these two cases with what is already published in the literature makes up a total of 17 RP patients with coexisting FHU.

CONCLUSIONS

This study confirms the association between FHU and RP; and a particularly stronger association with Usher syndrome type II. Although infectious agents seem to play a role, the cause for this significant correlation is still unclear.

Fuchs' heterochromic cyclitis

Fuchs' heterochromic cyclitis (FHC) is a chronic anterior segment inflammatory syndrome that accounts for 2 to 3% of all uveitis cases. The etiology is unknown, but Herpes simplex, ocular toxoplasmosis and rubella infection have been implicated in the pathogenesis of the disease. It occurs more commonly in the third and fourth decades of life with an equal gender distribution. Patients are usually asymptomatic but may present with floaters and blurry vision. There is a mild but persistent anterior chamber reaction with diffuse and characteristic white stellate keratic precipitates. Iris and trabecular meshwork show abnormal vessels that may sometimes lead to a hyphema. Synechia formation is uncommon. Heterochromia is considered an important feature and accounts for the name, but it is variable depending on the intensity of the anterior stromal atrophy, initial iris color and amount of pigment in the iris pigmented epithelium. Progression of the disease is associated with cataract formation and glaucoma. Anti-inflammatory treatment is not indicated for the low-grade anterior chamber reaction seen in Fuchs' patients. Occasionally, a short course of corticosteroids is indicated if a symptomatic exacerbation occurs. The long-term prognosis is good, and patients usually maintain a visual acuity of 20/40 or better.