Acquired immune deficiency syndrome (AIDS), also known as HIV/AIDS, is caused by infection with the human immunodeficiency virus (HIV). It is transmitted through bodily fluids and commonly occurs in individuals with a history of promiscuous sexual activity, homosexuality, intravenous drug use, or the use of blood products. Vertical transmission is a common cause of infection in children. HIV attacks CD4+ T lymphocytes, leading to a loss of immune function. Ocular involvement can occur at various stages of the disease, with the primary causes of blindness being opportunistic infections and neoplasms affecting the eye.
Irregularities in the lumens of microvessels in the bulbar conjunctiva, segmental blood column, microaneurysms, capillary narrowings, and constrictions of small arteries may be seen. Retinal manifestations include cotton-wool spots, flame-shaped and blot hemorrhages in the posterior pole, Roth spots, microaneurysms, and vascular sheathing. Macular edema and exudation may also occur.
AIDS-related ocular infections include:
- Cytomegalovirus retinitis;
- Toxoplasmic retinochoroiditis;
- Herpes zoster ophthalmicus, which may present as an initial symptom and is characterized by severe skin rash and prolonged disease course, often accompanied by keratitis and uveitis;
- Varicella-zoster virus-associated retinitis or acute retinal necrosis;
- Keratitis, including herpetic, fungal, or bacterial keratitis;
- Endophthalmitis, which is most commonly fungal in etiology.
AIDS-related ocular tumors include:
- Kaposi sarcoma, presenting as purplish, red-blue, or dark brown macules, papules, plaques, or nodules, which may ulcerate.
- Orbital Burkitt lymphoma, manifesting as ptosis, ocular motility disorders, and diminished or absent pupillary light reflexes.