Microbial keratitis

Thirty thousand cases of microbial keratitis occur annually in the United States.18 Microbial keratitis encompasses bacterial, fungal, and Acanthamoeba keratitis.19 Only bacterial keratitis, the most common form, is discussed here. 

In contact lens wearers, poor lens maintenance can lead to sight-threatening microbial keratitis, relating to Pseudomonas aeruginosa or Acanthamoeba infection, and advice must be sought from their contact lens practitioner or doctor. 

The Ofloxacin Smdy Group. Ofloxacin monotherapy for the primary treatment of microbial keratitis. A double-masked, randomized, controlled trial with conventional dual therapy. Ophthalmology 1997 104 1902-1909. 

Treatment of microbial keratitis is started immediately irrespective of whether microbiologic evaluation has been performed. The best antimicrobial agent or agents to use initially is debated in the ophthalmic literature. The two main choices for initial antibiotic treatment are the combination of two fortified antibiotics, such as cefazolin and tobramycin, or monotherapy with topical fluoroquinolones. Just as with the decision to culture, the choice of antibiotic is often influenced by history and clinical presentation. Milder presentations, in low-risk... 

Infiltrative events includes six subcategories microbial keratitis, CL-induced peripheral ulcer, CL-induced red eye, infiltrative keratitis, asymptomatic infiltrative keratitis, and asymptomatic infiltration... 

Aasuri MK,Venata N, Kumar VM. Differential diagnosis of microbial keratitis and contact lens-induced peripheral ulcer. Eye Contact Lens 2003 29(1 suppl) S60-S62 discussion S83-S84, SI92-SI94. 

DanieU M. Overview initial antimicrobial therapy for microbial keratitis. BrJ Ophthalmol 2003 87 1172-1174. 

DanieU M, MUls R, Morlet N. Microbial keratitis what s the preferred imtial therapy BrJ Ophthalmol 2003 87 1167. 

Keay L, Edwards K, Naduvilath T, et al- Microbial keratitis predisposing factors and morbidity Ophthalmology 2006 113 109-116. 

MaUari PLT, McCarty DJ, DameU M, et al. Increased incidence of corneal perforation after topical fluoroquinolones treatment for microbial keratitis. Am J Ophthalmol 2001 131 131-133. 

Stapleton F. Contact lens-related microbial keratitis what can epidemiologic studies teU us Eye Contact Lens 2003 29(1 suppl) S85-S89 discussion S115-118, S192-S194. 

Dart JK, Stapleton F, Minassian D. Contact lenses and other risk factors in microbial keratitis. Lancet 1991 338 (8768) 650-3. 

Anaphylactoid keratitis Allergic contact keratitis Irritative or toxic keratitis Phototoxic keratitis Toxic calcific band keratopathy Pseudotrachoma Cumulative deposition Microbial imbalance... 

Topical NSAIDs should be used with caution in ulcerative keratitis since their effects on comeal microbial infections and enzymolysis are not known and there is anecdotal evidence of comeal "melting" associated with their use. It should be noted that carprofen, an arylpropionic acid NSAID, has been shown to increase the expression of MMP9 zymogen in equine chondrocytes in vitro. Suppression of comeal angiogenesis by topical NSAIDs is likely to impede local comeal defense mechanisms and subsequently delay repair, particularly in deep stromal injury. Concurrent topical bactericidal antibiotics should always be used in conjunction with topical NSAIDs in ulcerative disease in all cases, the therapeutic benefits of topical NSAID therapy should be weighed against the possibility of any untoward effects. 

Moore C P, Collins B K, Fales W H 1995 Antibacterial susceptibility patterns for microbial isolates associated with infectious keratitis in horses 63 cases (1986-1994). Journal of the American Veterinary Medical Association 207 928-933... 

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