Lymphoma masquerading as occlusive retinal vasculitis: A case study

PURPOSE: To describe a case of retinal lymphoma presenting as an occlusive retinal vasculitis without vitritis that was exquisitely responsive to intravitreal dexamethasone implant (IVDI). OBSERVATION: A 66-year old male presented with decreased vision in the right eye and was diagnosed with occlusive retinal vasculitis and prominent cystoid macular edema though he lacked vitritis. A complete systemic workup for infectious, inflammatory, and infiltrative etiologies was unremarkable. Intravenous methylprednisolone and cyclophosphamide had no clinical effect. Due to persistent perivascular exudates and refractory macular edema, IVDI was administered with marked improvement in vision and clinical findings. Subsequent retinal vasculitis in the left eye responded to IVDI as well. The patient remained disease free for months while on weekly adalimumab. He then presented with acute vision loss in the left eye due to a lymphomatous subretinal infiltration and a new lesion in the corpus callosum. He has remained disease free for more than two years after intravitreal methotrexate injections and rituximab with an autologous stem cell transplant. CONCLUSION AND IMPORTANCE: Lymphoma may present as an occlusive retinal vasculitis without vitritis and can be masked due to its response to IVDI.