Ocular Infections

•Infections of the eye can involve the ocular surface and adnexal structures, intraocular structures, or both.•Infections of the ocular surface and adnexal structures often result from invasion by commensals when normal barriers are disrupted, and include infectious blepharitis, conjunctivitis, keratitis, dacryocystitis, and orbital infection.•Intraocular infections may arise secondary to local injury or occur as part of a systemic process. A large number of viruses, bacteria, fungi, protozoa, and helminths can cause intraocular disease. Sometimes ocular abnormalities are the only outward clinical manifestation of systemic infectious disease.•Examination of specimens from ocular tissues or ocular fluids can facilitate diagnosis of ocular infectious diseases, and may assist in the diagnosis of systemic infections.•Treatment of ocular disorders typically involves topical administration of antimicrobials and anti-inflammatory drugs, as well as specific therapy that is directed at underlying causes. Systemic antimicrobial drugs or glucocorticoids are occasionally required.