Identification of Pseudomonas aeruginosa by using a disk of phenanthroline and 9-chloro-9-[4-(diethylamino)phenyl]-9,10-dihydro-10-phenylacridine hydrochloride and by cell agglutination testing with monoclonal antibodies.

To establish a simple identification procedure for Pseudomonas aeruginosa, we developed a disk consisting of phenanthroline and 9-chloro-9-[4-(diethylamino)phenyl]-9,10-dihydro-10- phenylacridine hydrochloride (PC disk). Nine of 248 P. aeruginosa isolates and all other oxidase-positive gram-negative isolates (143 isolates) had clear inhibition zones around the PC disk. Of these nine P. aeruginosa isolates, seven produced a blue, blue-green, or green pigment on Mueller-Hinton agar after 24 h of incubation. The sensitivity and specificity of the PC disk susceptibility test in combination with pyocyanin production were 99 and 100%, respectively. Ten P. aeruginosa isolates showed no agglutination reactions with monoclonal antibodies against P. aeruginosa (96% sensitivity and 100% specificity).