A 67-year-old man has six months of progressive bilateral floaters and blurred vision diagnosed as chronic vitritis, which worsened despite repeated corticosteroid therapy. Fundus shows faint deep yellow-white subretinal infiltrates. Vitreous sampling is indicated primarily to establish:

• A Cytological evidence of large B-cell lymphoma ✓
• B Polymerase chain reaction for tuberculosis DNA
• C Vitreous culture for bacterial endophthalmitis
• D Serum angiotensin converting enzyme correlation

Explanation

Primary vitreoretinal lymphoma is the classic masquerade syndrome of older age, presenting as chronic steroid-resistant vitritis with deep subretinal deposits sometimes described as leopard spotting. Diagnosis rests on vitreous cytology showing atypical large lymphoid cells, aided by an elevated interleukin-10 to interleukin-6 ratio. Steroids temporarily shrink the tumour, so worsening despite treatment is itself a warning sign, and infectious cultures would miss a malignancy.

Reference: American Academy of Ophthalmology Basic and Clinical Science Course, Section 9: Intraocular Inflammation and Uveitis, 2022-2023 ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.