A 62-year-old woman has progressive bilateral vitritis and retinal infiltrates that have not responded to repeated courses of systemic corticosteroids. Vitreous biopsy shows large atypical lymphocytes. The most useful adjunctive diagnostic marker in the vitreous fluid is:

• A Low glucose with negative cytology
• B Elevated interleukin-6 with normal interleukin-10
• C Elevated angiotensin-converting enzyme
• D Elevated interleukin-10 with low interleukin-6 ✓

Explanation

Primary intraocular lymphoma, the classic masquerade syndrome of steroid-resistant vitritis in older adults, secretes IL-10, giving a high IL-10 to IL-6 ratio in the vitreous. Cytology may be negative on early sampling, so cytokine analysis raises suspicion and guides repeat biopsy. An elevated IL-6 pattern suggests inflammatory uveitis, ACE relates to sarcoidosis, and low glucose with negative cytology alone does not establish malignancy.

Reference: Ryan's Retina, 6th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.