Abstract
Subretinal fibrosis and uveitis syndrome is a rare, potentially devastating, posterior uveitis of unknown aetiology, characterised bilaterally by initial multifocal choroiditis with later progressive subretinal fibrosis. We report a rare case of unilateral subretinal fibrosis and uveitis syndrome. To date, there are only two case reports of unilateral disease. Our patient presented with unilateral blur and was found to have reduced visual acuity. A Bartonella profile was positive and a diagnosis of Bartonella posterior uveitis was made. Several positive ocular findings in the anterior chamber and on fundoscopy consistent with the syndrome were found. When steroid therapy alone could no longer control active inflammation, the immunosuppressive agent mycophenolate was added. Over time subretinal fibrosis became established sparing the macula and associated complications occurred, but with mycophenolate, at four years, our patient’s visual acuity had improved and remains stable. Moreover, four years after her initial presentation, her condition remains strictly unilateral.
Introduction
Bilateral progressive subretinal fibrosis with initial multifocal choroiditis defines subretinal fibrosis and uveitis syndrome (SFU), a rare potentially devastating posterior uveitis for which the aetiology is unknown. 1
We report a rare case of unilateral subretinal fibrosis with uveitis.
Case report
An 18-year-old mildly myopic Caucasian female presented with a 5–6 week history of blur in the supero-temporal aspect of her left visual field, colour disturbance and a pulsing sensation. Her medical and ocular history was unremarkable.
Visual acuities were 6/9 right eye and 6/12 left eye. She had a left relative afferent pupillary defect, a left supero-temporal visual field defect, with mild anterior chamber and anterior vitreous activity.
Fundoscopy revealed a swollen left optic nerve head, a patch of pale oedematous retina nasal to the disc, and small discrete yellow chorioretinal spots. Anterior segment and fundoscopy of the right eye was unremarkable.
Serological investigations included a Bartonella profile since the patient reported being scratched by a cat. Fundus photography, OCT imaging and fluorescein angiography were also performed.
A diagnosis of Bartonella posterior uveitis in the left eye was made and the patient was commenced on ciprofloxacin 500 mg BD daily. During bouts of inflammation, the patient was prescribed systemic corticosteroids, later being tapered and discontinued. When corticosteroids alone failed to control the patient’s condition at 25 months, the immunosuppressive agent, mycophenolate 500 mg BD, was prescribed.
Over time subretinal fibrosis became established, sparing the macula Fundus fluorescein angiography showing areas of early hypofluorescence and late stained lesions (active) and scars (resolved). Fundus photograph showing fibrotic scarring and a macular star. Fundus photograph of the normal right eye.
At 47 months, the posterior segment remained inactive with the patient continuing to take mycophenolate 1 mg BD. Her VA had improved and remained stable at 6/9 left eye (and 6/6 right eye).
Discussion
SFU has an unknown aetiology. Some researchers have however postulated an autoimmune aetiology whereby retinal pigment epithelium destruction is initiated by antibody-mediated inflammation together with complement and immunoglobulin deposition.2,3
Characteristic features of this syndrome include mild anterior or posterior uveitis, and small, multiple and transient white-yellow retinal pigment epithelium or choroidal lesions in the posterior pole and mid-periphery. These lesions may enlarge and coalesce over weeks to months to form areas of white subretinal fibrosis, or may gradually fade. Patients clinically present reporting acute onset visual loss or blurred vision. Other symptoms may include metamorphopsia, scotomas and photopsias. 1
Palestine et al. 2 described SFU as a bilateral condition affecting young myopic female patients. Despite clinical findings revealing bilateral involvement, patients typically report only unilateral symptoms. However, months later, the initially asymptomatic fellow eye may become involved. 1 Our patient remains to have unilateral disease four years after her initial presentation. A limited number of unilateral cases have been reported.4,5 Despite our patient developing a macular star together with optic disc oedema and secondary exudative retinal detachment, she continues to have good vision in the absence of active disease.
We surmise that following cat-scratch disease acquired by our patient, residual antigens remained in her left eye from the acute Bartonella infection. This ultimately resulted in an autoimmune chronic inflammatory process leading to a fibrotic response.2,6
Treatment for SFU remains contentious and ill defined. In severe cases, the early use of steroids and systemic immunosuppression may be of benefit. SFU, particularly once subretinal fibrosis has occurred, has a poor prognosis and it is common to have recurrences. 1 Infliximab has been trialled in a patient unresponsive to immunosuppressive therapy with very promising results, as has rituximab, suggesting that TNF-alpha monoclonal antibody therapy may be used in the so-far limited armoury of treatment for SFU.7,8
Conclusion
SFU can present and remain unilateral and asymmetric. Patients with SFU syndrome need to be diagnosed and treated promptly in order to prevent irreversible fibrotic changes and visual loss. In unilateral SFU, the unaffected eye must be closely monitored for signs of disease activity. Clinicians should be aware that Bartonella infection can result in an autoimmune chronic inflammatory process.
Footnotes
Authors’ contributions
Patient consent
Obtained.
Declaration of conflicting interests
None declared.
Funding
This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.