Keratitis

Etiology
- Viral: HSV, adenovirus
- Bacterial: Strep pneumo, Staph aureus, Pseudomonas
- Protozoa: Acanthamoeba
- chemicals

Signs/Symptoms
- Severe pain, corneal swelling, clouding, limbus erythema, hypopyon, cataracts; contact lens with history of amebic infection

Treatment
- specific antibiotics for bacterial/fungal infections; keratoplasty, acyclovir

Dendritic Keratitis
- HSV infection of cornea: branching treelike pattern on fluorescein staining = "dendrite"
- pain, photophobia, tearing, blepharospasm, conjunctival infection
- Specific Tx: mech debridement of corneal epith to remove source of infxn; 5-iodo-2'-deoxyuridine (IDU), topical vidarabine, or most commonly, vidarabine
- cycloplegic agent to relieve pain from ciliary muscle spasm
- Avoid overly aggressive antiviral tx, since itself can be toxic to the cornea
- topical corticosteroids exacerbate superficial herpetic dz; so always avoid eye drops with steroids and abx, unless indications are clear
- infants born to moms with HSV should be examined carefully for signs of ocular involvement; use IV acyclovir for treatment of ocular herpes in newborns.