WBCs in the vitreous (vitritis) are more associated with which condition?

• A. Retinitis
• B. Choroiditis
• C. Macular edema
• D. Optic neuritis

Answer: (A)

WBCs in the vitreous signify inflammation in the posterior segment where inflammatory cells spill into the gel that fills the eye. The condition most likely to cause this vitreous inflammation is retinal involvement—retinitis. When the retina is inflamed or necrotic, inflammatory cells commonly enter the vitreous, leading to visible cells or “vitritis.” A classic example is retinochoroiditis, such as toxoplasmosis, where you often see dense vitritis described as a “headlight in the fog.”

Inflammation confined mainly to the choroid tends to spare the vitreous, so vitritis is less prominent. Macular edema reflects fluid buildup rather than cells, and optic neuritis centers on the optic nerve with little or no required vitreous involvement. So the presence of vitreous white blood cells aligns most with retinitis.