Keratitis isolates

Kowalski RP, et al. Gatifloxacin and moxifloxacin an in vitro susceptibility comparison to levofloxacin, ciprofloxacin, and ofloxacin using bacterial keratitis isolates. Am. J. Ophthalmol., 2003, 136, 500-505. 

In one isolated report, Russian rubber workers exposed to concentrations averaging 271-542 ppm with excursions to 677 ppm were reported to suffer keratitis, rhinitis, headache, leukopenia, neutrophilia, lymphocytosis, and... 

Narasimhan S, Madhaven HN, Therese KL. Development and apphcation of an in vitro susceptibility test for Acanthamoeba species isolated from keratitis to polyhexamethylene biguanide and chlorhexidine. Cornea 2002 21(2) 203-205. 

TSPK is a chronic epithelial keratitis of unknown etiology, suggested to be due to chronic subclinical viral infection in the deep layers of the basal epithelium. Support for this theory includes the protracted coruse of this condition, its tendency to recur, the lack of effect by antibiotics on its clinical course, and lack of bacterial isolation from eyes affected by the condition. The clinical presentation of corneal mononuclear cell infiltrates, the rapid resolution of these infiltrates with topical steroids, and their rapid reappearance if topical steroids are stopped too quickly support the possibility that the primary presentation is a typical immunologic response. 

Keratitis and keratoconjunctivitis in association with equine herpes virus (EHV) respiratory disease has been recorded in foals. In adult horses, putative viral superficial keratitis, unassociated with systemic disease, is commonly seen in practice in the UK and may occur sporadically in the USA and mainland Europe. No specific virus has been isolated consistently from affected eyes and the suspected viral etiology is based largely upon the response to topical antiviral treatment. The disease is characterized by acute ocular pain and focal epitheliopathy. Two specific forms of the disease are encountered. Type 1 is characterized by epithelial fissuring, which occasionally results in dendritic or, rarely, frankly ulcerative lesions. Type 2 is characterized by shallow pimctate ulceration. 

Antimicrobial susceptibility patterns of fungi isolated from horses with ulcerative keratomycosis. American Journal of Veterinary Research 59 138-142 Brooks D E, Andrew S E, Biros D J et al 2000a Ulcerative keratitis caused by beta haemolytic Streptococcus equi in 11 horses. Veterinary Ophthalmology 3 121-126 Brooks D E, Andrew S E, Denis H M et al 2000b Rose Bengal positive epithelial microerosions as a manifestation of equine keratomycosis. Veterinary Ophthalmology 3 83-86... 

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... 

Results in ocular herpes keratitis are usually more positive and there is no doubt of the value of the drug in this form of infection [191, 192]. Some patients have been found to be resistant to treatment but in only 2 out of 12 such patients in one trial was the isolated virus found to be actually more drug-resistant than the normal wild-type virus. In this paper [192] the value of IDUR in herpes keratitis of man was critically assessed from the information available in mid-1969. 

Raza SK, Mallet AI, Howell SA, Thomas PA (1994) An In-Vitro Study of the Sterol Content and Toxin Production of Fusarium Isolates from Mycotic Keratitis. J Med Microbiol 41 204... 

As previously mentioned, systemic delivery is limited because of the isolation of ocular tissues from the systemic circulation thus, topical delivery is often the preferred administration route owing to ease of access and patient compliance, particularly when treating infections of the anterior segment such as keratitis sicca, conjunctivitis, or blepharitis and diseases such as glaucoma or uveitis that require the drug to be diffused across the corneal barrier [19,20]. However, drainage, lacrimation and tear dilution, tear turnover, conjunctival absorption, and the corneal epithelium all limit corneal drug penetration [21,22]. 

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