Cytomegalovirus retinitis mimicking intraocular lymphoma

Patrick Gooi¹, James Farmer², Bernard Hurley³, Elliott Brodbaker⁴

¹Department of Ophthalmology, University of Calgary, Calgary, Alberta, Canada; ²Department of Pathology and Lab Medicine University of Ottawa and The Ottawa Hospital, Ottawa, Ontario, Canada; ³Department of Ophthalmology, University of Ottawa Eye Institute and The Ottawa Hospital, Ottawa, Ontario, Canada; ⁴Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada

Abstract: We present a case of an unusual retinal infiltrate requiring retinal biopsy for definitive diagnosis. A 62-year-old man with treated lymphoma presented with decreased vision in the right eye associated with a white retinal lesion, which extended inferonasally from an edematous disc. Intraocular lymphoma was considered as a diagnosis; thus, the patient was managed with vitrectomy and retinal biopsy. Cytological analysis of the vitreous aspirate could not rule out a lymphoproliferative disorder. The microbial analysis was negative. Histology of the lesion showed extensive necrosis and large cells with prominent nucleoli. To rule out lymphoma, a battery of immunostains was performed and all were negative. However the limited amount of tissue was exhausted in the process. Subsequently, a hematoxylin and eosin (H/E) slide was destained, on which a CMV immunostain was performed. This revealed positivity in the nuclei and intranuclear inclusions within the large atypical cells. A diagnosis of CMV retinitis was made. Retinal biopsy may provide a definitive diagnosis and direct patient care toward intravenous gancyclovir in the case of CMV or toward radiation and chemotherapy for intraocular lymphoma. When faced with a limited amount of tissue, destaining regular H/E slides is a possible avenue to performing additional immunohistochemical studies.

Keywords: CMV retinitis, retinal biopsy, immunohistochemistry, destaining