Ocular nocardia infections with special emphasis on the cornea

Nocardia are aerobic, gram-positive, nonmotile and branching filamentous ba cteria. Corneal infection by Nocardia is rare. Trauma is the most common pr edisposing factor. Isolated case reports of nocardial infection associated with contact lens wear and laser in situ keratomileusis (LASIK) have been r eported. The clinical picture usually consists of superficial patchy infilt rates, which may be arranged in a wreath pattern. Presence of gram-positive , branching, beaded filaments that stain with 1% acid-fast stain (using 1% sulfuric acid, modified Kinyoun's method) in smears of corneal scrapings is suggestive of nocardial infection. Nocardia grow on commonly used media as tiny, white, dry colonies. Available knowledge and clinical experience sug gest that although sulfacetamide eyedrops can be tried as the initial drug, trimethoprim-sulfamethoxazole and amikacin are effective drugs. Once thera py is initiated, the infiltrate responds promptly and resolves, forming a c orneal scar with or without vascularization, and good visual recovery can b e expected. (Surv Ophthalmol 45:361-378, 2001. (C) 2001 Elsevier Science In c. All rights reserved.).