Therapeutic window of opportunity in the acute uveitic phase of Vogt-Koyanagi-Harada disease: Prevention of late autoimmune complications by early intervention

PURPOSE

To determine relationship between timing of treatment initiation and disease outcomes and whether a therapeutic window of opportunity exists in initial-onset acute uveitis associated with Vogt-Koyanagi-Harada disease.

METHODS

Retrospective analysis of 112 patients (224 eyes). Main outcome measures were final visual acuity, progression to chronic recurrent evolution, development of complications, particularly 'sunset glow fundus', and drug-free remission cure of uveitis.

RESULTS

Forty-six patients (92 eyes) presented in the phase preceding anterior segment (AS) inflammation (early presentation) and 66 patients (132 eyes) had AS inflammation at presentation (late presentation). In significantly more eyes in the early presentation group (85.9%), final visual acuity of 20/20 was achieved compared with those in the late presentation group (66.7%) (p = 0.001). None of the eyes in the early presentation group progressed to chronic recurrent evolution and none developed 'sunset glow fundus', whereas in the late presentation group, 28.8% of the eyes progressed to chronic recurrent evolution (p < 0.001) and 56.1% developed 'sunset glow fundus' (p < 0.001). Patients in the early presentation group were able to discontinue treatment without relapse of inflammation at significantly shorter time intervals compared to patients in the delayed presentation group (p < 0.001). In the late presentation group, logistic regression analysis demonstrated that presenting clinical features predicting unfavourable outcomes were posterior synechiae (odds ratio = 4.03; 95% confidence interval [CI] = 1.29-12.23), bullous exudative retinal detachment extending to the periphery (odds ratio = 3.35; 95% CI = 1.53-7.32) and female gender (odds ratio = 2.05; CI = 1.08-3.90).

CONCLUSIONS

Our findings suggest that the window of opportunity lies in the phase preceding AS inflammation and initiation of effective treatment during this phase results in cure of uveitis and prevents blinding complications.

New Perspectives on the Immunopathogenesis and Treatment of Uveitis Associated With Vogt-Koyanagi-Harada Disease

Uveitis associated with Vogt-Koyanagi-Harada (VKH) disease is a bilateral, chronic, granulomatous autoimmune disease associated with vitiligo, poliosis, alopecia, and meningeal and auditory manifestations. The disease affects pigmented races with a predisposing genetic background. Evidence has been provided that the clinical manifestations are caused by a T-lymphocyte-mediated autoimmune response directed against antigens associated with melanocytes in the target organs. Alongside of T lymphocytes, autoreactive B cells play a central role in the development and propagation of several autoimmune diseases. The potential role of B lymphocytes in the pathogenesis of granulomatous uveitis associated with VKH disease is exemplified within several studies. The early initial-onset acute uveitic phase typically exhibits granulomatous choroiditis with secondary exudative retinal detachment and optic disc hyperemia and swelling, subsequently involving the anterior segment if not adequately treated. The disease eventually progresses to chronic recurrent granulomatous anterior uveitis with progressive posterior segment depigmentation resulting in "sunset glow fundus" appearance and chorioretinal atrophy if not properly controlled. Chronically evolving disease is more refractory to treatment and, consequently, vision-threatening complications have been recognized to occur in the chronic recurrent phase of the disease. Conventional treatment with early high-dose systemic corticosteroids is not sufficient to prevent chronic evolution. Addition of immunomodulatory therapy with mycophenolate mofetil as first-line therapy combined with systemic corticosteroids in patients with acute initial-onset disease prevents progression to chronic evolution, late complications, vitiligo, and poliosis. Furthermore, patients under such combined therapy were able to discontinue treatment without relapse of inflammation. These findings suggest that there is a therapeutic window of opportunity for highly successful treatment during the early initial-onset acute uveitic phases, likely because the underlying disease process is not fully matured. It is hypothesized that early and aggressive immunosuppressive therapy will prevent remnant epitope generation in the initiation of the autoimmune process, the so-called primary response. B cell depleting therapy with the anti-CD20 monoclonal antibody rituximab is effective in patients with refractory chronic recurrent granulomatous uveitis. The good response after rituximab therapy reinforces the idea of an important role of B cells in the pathogenesis or progression of chronic recurrent uveitis associated with VKH disease.