Mechanisms, Pathophysiology and Current Immunomodulatory/Immunosuppressive Therapy of Non-Infectious and/or Immune-Mediated Choroiditis

A retrospective study describing the effective exchange of total blood plasma for disease control in the exacerbation of serpiginous choroiditis

INTRODUCTION

Serpiginous choroiditis presents with large yellow-white exudative lesions that occur near the optic nerve papillae, that progresses slowly with repeated relapses and cures. Although infection and autoimmunity have been implicated, the cause is unknown.

METHODS

A man was diagnosed with serpiginous choroiditis on clinical and other examinations. He started treatment with oral corticosteroids, cyclophosphamide, adalimumab, azathioprine, rituximab, and mycophenolate mofetil. Only the steroids and cyclophosphamide had a therapeutic effect. Plasma exchange was initiated, and the lesions quickly resolved.

RESULTS

Disease control has been maintained by plasma exchange and cyclophosphamide during flare-ups in the fall and winter, suggesting that plasma exchange is effective in the treatment of serpiginous choroiditis.

CONCLUSION

The reproducible response with each recurrence suggests a strong association between the disease and autoimmunity. Furthermore, that some, as yet unknown, autoantibodies are involved in the pathogenesis of serpiginous choroiditis.

CORRELATION BETWEEN INFLAMMATORY FOCI REACTIVATION AND ATROPHY GROWTH IN EYES WITH IDIOPATHIC MULTIFOCAL CHOROIDITIS

PURPOSE

To correlate the number of inflammatory reactivations in atrophic foci of multifocal choroiditis (MFC) with their growth rate over a 4-year span.

METHODS

Comparative case series. Optical coherence tomography scans of patients affected by MFC were reviewed to identify reactivations within or at the margin of atrophic MFC foci. The area of selected lesions was semiautomatically delineated on fundus autofluorescence images and recorded at yearly intervals for a total follow-up of 4 years. The main outcome was the difference in annual square-root transformed area growth rate between lesions that reactivated and lesions that did not.

RESULTS

Sixty-six foci of 30 eyes of 24 patients were included. All MFC foci enlarged over time, but the annual growth rate was more than double in lesions that reactivated compared with those that did not (mean [SD], 0.051 [0.035] vs. 0.021 [0.015] mm/year, P < 0.001), despite starting from comparable baseline areas. For each additional inflammatory reactivation, the annual growth rate increased by more than 20% (+0.009 mm/year, 95% CI [0.006, 0.012], P < 0.001).

CONCLUSION

Increasing number of reactivations of atrophic foci led to proportional increments in their growth rate, highlighting the need for a tight control of inflammatory relapses in patients affected by MFC.

Diagnosis, Mechanisms, and Differentiation of Inflammatory Diseases of the Outer Retina: Photoreceptoritis versus Choriocapillaritis; A Multimodal Imaging Perspective

Background and aim: Inflammatory diseases that affect the outer retina do so by different mechanisms. Some of them result from the direct, primary involvement of the outer retina (primary photoreceptoritis) such as acute zonal outer occult retinopathy (AZOOR). Others affect the photoreceptors secondarily due to the inflammatory involvement of the choriocapillaris. This results in choriocapillaris non-perfusion that damages the photoreceptors due to the ensuing ischaemia, a mechanism characterising primary inflammatory choriocapillaropathies (PICCPs) such as multiple evanescent white dot syndrome (MEWDS), idiopathic multifocal choroiditis (MFC), and others. Thanks to multimodal imaging (MMI), it is now possible to differentiate between these two mechanisms of outer retinal damage. The aim of this study is to determine the MMI characteristics that allow us to differentiate primary photoreceptoritis, including AZOOR, from PICCPs such as MEWDS and MFC. Methods: A series of eight PICCPs cases (five typical MEWDS and three typical active MFC cases) and four typical primary photoreceptoritis/AZOOR cases (five eyes) that had undergone complete MMI investigation, including fundus photography (FP), blue light fundus autofluorescence (BL-FAF), spectral domain optical coherence tomography (SD-OCT), OCT angiography (OCT-A, when available), fluorescein angiography (FA), and indocyanine green angiography (ICGA) were analysed, pointing out the differences that allow us to distinguish primary photoreceptoritis from PICCPs. Results: All primary photoreceptoritis/AZOOR cases showed (1) faint fundus pallor around the fovea, (2) BL-FAF hyperautofluorescence, (3) loss of photoreceptor outer segments (PROS) on SD-OCT, (4) absence of choriocapillary drop-out on OCT-A, (5) normal FA or faint FA hyperfluorescence, and (6) conserved ICGA fluorescence/no hypofluorescent areas; (1), (2), (3), and (5) indicated loss of photoreceptor outer segments, and (4) and (6) indicated conserved choriocapillaris circulation. For PICCPs, (a) fundus showed discreet white dots or none (in MEWDS) and punched-out scars in MFC, (b) BL-FAF hyperautofluorescence, (c) loss of PROS on SD-OCT, (d) FA faint hyperfluorescence in MEWDS, also minimal in active MFC lesions (e) in all cases ICGA hypofluorescent areas; (b) and (c) indicating loss of PROS, and (e) indicating choriocapillaris non-perfusion in all cases. The OCT-A did not show consistent findings with faint or no capillary drop-out in MEWDS and MFC. Conclusions: MMI combining the SD-OCT and BL-FAF clearly showed loss of PROS in both groups, while the ICGA determined whether this was due to choriocapillaris non-perfusion in PICCPs or whether the choriocapillaris was intact in case of primary photoreceptoritis. The FA and OCT-A were found to be less useful and/or less sensitive for the appraisal of both these entities.