## **Core Concept**
Ocular manifestations in AIDS (Acquired Immunodeficiency Syndrome) are diverse and can affect various parts of the eye. These manifestations are primarily due to opportunistic infections and neoplasms that take advantage of the compromised immune system. Cytomegalovirus (CMV) retinitis is one of the most common and significant ocular manifestations.

## **Why the Correct Answer is Right**
The correct answer, **C. CMV retinitis**, is right because CMV retinitis is a well-known and serious ocular complication in patients with AIDS. It occurs when the CMV virus infects the retina, leading to retinal necrosis, hemorrhage, and vitreitis. This condition can cause severe visual impairment and is often seen in patients with very low CD4 counts (<100 cells/μL). The retina shows characteristic "pizza pie" or "cheese and ketchup" appearance due to areas of retinal necrosis and hemorrhage. ## **Why Each Wrong Option is Incorrect** - **Option A:** While cotton wool spots are a common finding in HIV patients, representing areas of retinal ischemia, they are not as specific or severe as CMV retinitis in the context of AIDS ocular manifestations. - **Option B:** Toxoplasmosis is another opportunistic infection seen in AIDS patients, causing toxoplasmic retinochoroiditis. However, it typically presents with a more localized lesion and not as diffuse retinal involvement as CMV retinitis. - **Option D:** While ocular involvement can occur in various systemic conditions, the specificity and severity of CMV retinitis make it a standout correct answer in the context of AIDS. ## **Clinical Pearl / High-Yield Fact** A key clinical pearl is that CMV retinitis often presents with a painless loss of vision and can be bilateral. A diagnostic clue is the presence of perivascular retinal necrosis. Early diagnosis and treatment, often with antiviral medications like ganciclovir, are crucial to prevent progression and vision loss. ## **Correct Answer:** . **CMV retinitis**