View source for Bacterial keratitis

''Bacterial keratitis is also often referred to as a [[corneal ulcer]], although these terms are not directly interchangeable because a cornea may harbor a bacterial infection (i.e bacterial keratitis) without having a loss of tissue (an ulcer), and a cornea may have an ulcer without a bacterial infection.''
==Background==
*Rapidly progressing, with corneal destruction as fast as within 24 hrs
*Corneal perforation is most sight threatening complication
*[[Strep]], [[staph]], [[pseudomonas]], [[enterobacteriaceae]]
*Risk factors
**[[Contact lens]] use
**Corneal surgery, [[ocular Trauma|trauma]]
**Chronic dry eye
**Recent corneal disease (viral, fungal keratitis)
**Immune deficiency, [[topical steroids]]

==Clinical Features==
[[File:PMC3520035 TOOPHTJ-6-110 F3.png|thumb|Bacterial keratitis due to [[Pseudomonas]] spp.]]
*[[Blurred vision]]
*Severe [[eye pain|pain]] and photophobia
*Perilimbic injection
*Normal pupil size
*Eyelid edema
*Mucopurulent exudate
*Posterior synechiae (iris adheres to cornea)

==Differential Diagnosis==
*[[Iritis]]
*[[Conjunctivitis]]
*[[Glaucoma]]
*[[UV keratitis]]
*[[Herpes zoster]]
*[[contact lens problems|Contact lens complication]]
*Fungal keratitis
*[[Bacterial keratitis]]
*Interstitial keratitis
*[[Herpes keratitis]]
*[[Endophthalmitis]]


==Evaluation==
*Topical anesthesia with proparacaine, as opposed to [[tetracaine]] which has bacteriostatic effects, limiting culture results
*Culture and gram stain of corneal ulcer edges, eyelids, conjunctiva, contact lenses
*[[ocular ultrasound|Ultrasound]] to assess for signs of endophthalmitis and other pathologies

==Management==
*Broad spectrum topical [[antibiotics]]; 1 drop q1 hr
**[[Tobramycin]] 14mg/ml
**Alternate with fortified [[cefazolin]] 50mg/ml
*Smaller corneal ulcers may be treated with [[moxifloxacin]] or [[gatifloxacin]] ophthalmic

==Disposition==
*Ophtho consult for possible perforation risk
*Eye patch in the interim

==See Also==
*[[Corneal ulcer]]

==References==
<references/>
*Murillo-Lopez F et al. Bacterial Keratitis. Aug 24, 2014. http://emedicine.medscape.com/article/1194028-overview.
[[Category:Ophthalmology]]