**Question:** The most common ophthalmic lesion in AIDS is -

A. Retinopathy
B. Uveitis
C. Chorioretinal scarring
D. Optic neuritis

**Core Concept:** AIDS stands for Acquired Immunodeficiency Syndrome, a severe form of HIV (Human Immunodeficiency Virus) infection. HIV primarily targets CD4+ T-cells, leading to a weakened immune system and increased susceptibility to opportunistic infections and cancers. AIDS is characterized by a CD4+ T-cell count less than 200 cells/mm³ or 10% of normal.

**Why the Correct Answer is Right:** The most common ophthalmic lesion in AIDS is **D. Optic neuritis**. This condition occurs due to the direct invasion of the optic nerve by HIV or indirectly by the immune system's dysregulation. Optic neuritis presents with pain on eye movement, visual impairment, and optic disc edema on examination.

**Why Each Wrong Option is Incorrect:**

A. **Retinopathy:** Although some microangiopathy can occur in AIDS, the most common retinopathy is from opportunistic infections like herpes simplex virus, toxoplasmosis, or cytomegalovirus. These are not directly related to HIV infection.

B. **Uveitis:** While uveitis can be seen in AIDS, the most common cause of uveitis is tuberculosis. AIDS-related uveitis is typically anterior and granulomatous, while AIDS-unrelated uveitis is typically posterior and non-granulomatous.

C. **Chorioretinal scarring:** Chorioretinal scarring is a sign of chronic HIV-related inflammation and infection, but it is not the most common ophthalmic manifestation in AIDS. Other manifestations like optic neuritis, toxoplasmosis, and herpes simplex virus infections are more common.

**Clinical Pearl:** AIDS presents with a spectrum of ophthalmic manifestations, including optic neuritis, toxoplasmosis, herpes simplex virus infections, and various other opportunistic infections. The correct answer (D) highlights the most common manifestation of AIDS in the eye, which is optic neuritis. This helps students understand the variety of ophthalmic manifestations in AIDS and how to differentiate them from other causes of optic neuritis like tuberculosis.