alcaligenes xylosoxidans keratitis following photorefractive keratectomy

purpose : infectious corneal ulceration is a serious potential complication of prk. although gram positive organisms are the most common pathogens, in this study we present the first case of gram negative bacilli keratitis, alcaligenes, after prk. case report : a 22-year-old man was referred to our institution due to infection following corneal refractive surgery. three days after surgery, the patient developed redness, very intense pain and blurred vision in the treated eye and he admitted with the clinical diagnosis of right eye post-prk keratitis. microscopic examination of the smear showed presence of gram negative bacilli and culture was positive for alcaligenes. he was treated with fortified vancomycin, amikacin and ciprofloxacin and clinical symptoms subsided after 3 days and uncorrected visual acuity (ucva) had improved to 6/10, but central haze remained. conclusion : alcaligenes xylosoxidans has rarely been reported to cause postoperative endophthalmitis and infectious keratitis. owing to a high degree of intrinsic antibiotic resistance, this organism presents a therapeutic challenge.    iranian journal of ophthalmology 200921(3):56-59 © 2009 by the iranian society of ophthalmology