Treatment and outcome of Nocardia keratitis

Objective. To report our experience in treatment and outcome of Nocardia ke ratitis. Methods, Medical and microbiology records of seven cases of cultur e-proven Nocardia keratitis seen between January 1997 and March 1999 were r eviewed retrospectively. In all patients, corneal scrapings were obtained f or direct microscopic evaluation and culture. Drug sensitivity was determin ed by the Kirby-Bauer disk-diffusion method. The minimum inhibitory concent ration of ciprofloxacin and amikacin for these isolates was determined by a gar dilution method. Response to medical therapy and the end result were an alyzed. Results. By the in vitro Kirby-Bauer disk-diffusion techniques, all isolates were sensitive to amikacin; six of these isolates were sensitive to gentamicin and four were sensitive to ciprofloxacin. The minimum inhibit ory concentration (MIC) of amikacin for all isolates by the agar-dilution t echnique was well below the MIC breakpoint for Nocardia resistance, whereas the MIC of ciprofloxacin was above the MIC breakpoint for Nocardia resista nce. All patients responded to medical therapy. The corneal infection resol ved in three patients after treatment with ciprofloxacin, in one patient af ter fortified gentamicin, and in three patients after fortified amikacin. O utcome details were available for six patients. There was good visual recov ery in four patients, with visual acuity of 20/25 or better in three. The c ornea of two patients developed nonvascularized scars, and in four patients in whom the infiltrates were peripheral, vascularization was seen. Conclus ions. Although patients of Nocardia keratitis may respond to other antibiot ics, amikacin appears to be a drug of choice. In this small series, when ap propriate therapy was initiated, Nocardia keratitis resolved promptly with good visual recovery.