Bacterial Corneal Ulcer

Ans. Neisseria meningitidis

Ans. Staphylococci

Ans. Pain

Ans. A i.e. Anterior capsular cataract

Ans. b. Pseudomonas

Pseudomonas Keratitis

• Pseudomonas aeruginosa is the MC gram-negative organism isolated from corneal ulcers and is a frequent cause of contact lens-associated keratitis^Q
• Source of Infection:
• These aerobic bacilli are found in moist environments^Q
• Frequently contaminate inadequately chlorinated swimming pools and hot tubs, ventilators, nebulizer and vaporizer solutions, and ophthalmic solution bottles^Q

Pseudomonas Keratitis

Pathophysiology:

• The organism readily adheres to damaged epithelium, and stromal invasion is rapid^Q.
• Pseudomonas keratitis tends to progress rapidly if inadequately treated.
• Most commonly, the organism produces destructive enzymes such as protease, lipase, elastase, and exotoxin, which results in necrotic, lipase, elastase, and exotoxin, which results in necrotic, soupy ulceration.
• The ulcer often extends peripherally and deeply within hours and can rapidly involve the entire cornea.
• Ring ulcers can develop, and the corneal epithelium peripheral to the primary ulcer typically develops a diffuse gray, ground-glass appearance.
• The corneal stroma appears to dissolve into a greenish yellow mucous discharge that fluoresces under ultraviolet (but not under cobalt blue) light.
• The suppurative ulcer frequently thins to a discemetocele that perforates^Q
• The ulcer is often associated with a marked anterior chamber reaction and hypopyon formation.
• Extensive keratitis can extend to the limbus and produce an infectious sclertis.