Pseudomonas aeruginosa: isolation from ocular tissues. Aeruginocin typing and its relationship to corneal pathogenicity in rabbits.

Fifty strains of Pseudomonas aeruginosa isolated from human eyes were aeruginocin typed by the method of Shriniwas (1974) using ten indicator strains. These belonged to types A1 (3), B (2), F1 (1) and 14 (1). Fifteen (30%) were nontypable and 28 (56.0%) were unclassifiable presenting twenty inhibition patterns. The strains showed a wide range of antibiotic sensitivities. The highest number of insensitive strains were those obtained from corneal ulcers. Experimental keratitis produced by strains of pseudomonas was either mild, moderate or severe and was unrelated to their source. Mild keratitis was produced by types UC 7-, UC 79- and 14 isolated from pre-operative, corneal ulcer and post-operative patients. Lesions of moderate severity were produced by types 189+ & A1 whereas the severest pathology was produced by UC 23478-, B and UC 810- types. The fact that strain 23478- always produced severest pathology irrespective of whether originated from group I, II, or IV strongly suggests relationship of pathogenicity with aeruginocin type.